| 00:09 | mm hmm. Um This is Okay. Yes sir. So from |
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| 00:22 | 1 to 4 we hear steady rights get him sediments supply and kind of |
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| 00:32 | aggregation aggregation gradation Then a step five falls by 20 m. But the |
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| 00:42 | supply is high. This is a five for me here. And we |
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| 00:46 | an evolution of the imperial steps. we see a steady build up |
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| 00:52 | Step six, Step 5, Step , Step 7 20 m. said |
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| 01:02 | sea level rise. Well you said . Step seven, there's step eight |
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| 01:09 | level rise by five m. I to mr playing critics again, the |
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| 01:16 | nine um Sea level is stable. . Supply is high again. She |
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| 01:22 | stayed within my supply nine and step . She never went by 5 10 |
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| 01:28 | m again. And I said mister which is the last step. |
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| 01:33 | On step four had a that was routed had a stable sea level and |
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| 01:42 | sediment supply. So the settlements were to flow from um the previous She |
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| 01:50 | up step three Used the abyssal plain here. And this was over then |
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| 01:56 | the sediment step nine. Okay. one thing I would advise you is |
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| 02:04 | me see if I can. Uh . Yeah. Just give me a |
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| 02:34 | here. Okay. Yes. you guys still there? Yes. |
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| 05:15 | . I'm having my usual problem I can't annotate or drawing anything on |
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| 05:23 | . Oh, should I stop sharing ? No because I want uh he |
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| 05:30 | sign into your account. You zoom . My apps don't work. My |
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| 05:34 | don't work so I can't draw So um mm hmm. I don't |
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| 05:41 | why this is doing this. Um . Do you have something to |
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| 06:00 | I do. But mine is on ipad. So I'm not actually I |
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| 06:06 | save it as a pdf and you're gonna try that comments. But |
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| 06:14 | look at what Andrew's done first and all maybe give some group comments. |
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| 06:19 | , sure. I'm still sharing. , Okay. Ah mm hmm. |
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| 06:31 | I don't know if you want to again and let her know that |
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| 06:35 | you know, she, I think said 8:00. Right? But |
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| 06:40 | I, I messaged her, she thinking it was nine our time. |
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| 06:46 | . Okay. So she'll be with shortly I guess. Yes. |
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| 07:49 | Good morning. Start the classes at mary. We're just having a look |
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| 08:01 | the assignments and I'm giving some So McDonough shared his Andrew is going |
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| 08:05 | try to get hers up. Mhm, mm hmm. Can you |
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| 08:38 | my screen? Yep. Yeah. I did the first few steps because |
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| 08:49 | actually did two versions I wasn't exactly with based on the way we did |
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| 08:56 | class yesterday and then the way it today, if the sediment supply should |
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| 09:05 | all the way down the slope or it's mhm. Um more like |
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| 09:12 | 2nd. Okay. And then, you just got the 1st 1st 3 |
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| 09:31 | done as so the first one I with the actual um I did a |
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| 09:41 | , 1st 4. Um and then I just drew in the sea level |
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| 09:45 | because then this is gonna be But since I wasn't sure which one |
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| 09:51 | more correct for the first four um I just did the two different |
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| 09:58 | . Okay. We haven't done the yet. Right. No. |
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| 10:01 | And again I said, did you some progress? But ah maybe have |
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| 10:10 | look at yours. You can stop . Angela. Thank you. Uh |
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| 10:33 | . Thanks. Mm hmm. So far as you got. Okay. |
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| 11:21 | what's what's almost in the middle here it's like blank space. Like is |
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| 11:26 | judging there or? Yeah, I wanted to drop like the deposits or |
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| 11:35 | . Okay. Mm hmm. So I'm, you can stop sharing |
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| 11:46 | . So I'm going to go through again with you a little bit. |
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| 11:49 | obviously it's it's it's very different when doing on your own versus having me |
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| 11:55 | you. But let me, so all mm hmm. Mm hmm. |
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| 12:33 | . So this is the exercise we're with, right? Um and one |
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| 12:41 | the things, so Mcguinness, you , you've got the whole thing down |
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| 12:46 | you would, but you ended up a clown a form that looks like |
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| 12:50 | . Okay. That's, that's not shape. So I really want you |
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| 12:55 | be very careful when you draw your platform. I think step one of |
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| 12:59 | member is high silent supply. No level rise, is that correct? |
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| 13:05 | . So that's gonna be horizontal line then you simply you match that geometry |
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| 13:13 | . Right. So you've got your rollover of your shore face, then |
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| 13:17 | got your slightly concave up shelf Okay? And then that's and then |
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| 13:23 | get that little spillover, little bit condensed section share. All right. |
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| 13:28 | then you can draw your sarcasm for one. Okay. So it says |
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| 13:34 | the sea level rises uh five So for step one Yes. |
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| 13:42 | Well then, yeah, I don't don't have the rules in front of |
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| 13:44 | . So a five m sea level would be it would be here. |
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| 13:51 | , then you roll roll unit Okay. And then you do a |
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| 13:58 | that thins a little bit and then little spillover. Okay, that's step |
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| 14:05 | . Then you can draw that, the base of the shore face and |
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| 14:11 | the non marine feces. Okay, step two Deborah Reis bundle of five |
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| 14:19 | . So there we go. five increasing supply Israel and follow my geometry |
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| 14:25 | rolls over. Okay. And then got that sending unit. Okay. |
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| 14:33 | . So Mcdonald's you wish that it something sort of looked like that as |
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| 14:37 | to something that looks like this. ? So I really want you to |
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| 14:42 | of preserve my geometry as much as can. Otherwise, otherwise the otherwise |
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| 14:47 | the the it'll start to look a strange. Okay. And then what |
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| 14:53 | the next step? Lot of five . We keep that. Okay. |
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| 15:03 | know, just decide how far you to take it and there's that roll |
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| 15:07 | . Okay. Then the next So you should be looking something like |
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| 15:17 | . Right? Yes, sir. Andrea you're doing things that look sort |
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| 15:21 | like this, right? That that's the geometry that I'm drawing, |
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| 15:27 | Yes, I did that yesterday. that I think that maybe where you're |
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| 15:30 | a little, you know, mixing chloroform I drew yesterday with the one |
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| 15:35 | drawing today. So you sort of the right idea. But just |
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| 15:41 | you know, stick to the contact in this in this exercise rather than |
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| 15:46 | from that we did yesterday. And then what's the next step? |
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| 15:50 | we've got 123 and four here. sea levels stable and high sediment |
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| 15:57 | Okay, So now we're going to a horizontal, it just moves |
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| 16:00 | Okay. Same thing, mm Now, in my example, I |
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| 16:11 | quite got the shelf edge yet. it's just condensed section out here. |
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| 16:14 | probably got too much stuff in but that's, you know, it's |
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| 16:17 | close enough, right? But now see the differences. Now we're In |
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| 16:21 | 1 to step. This is step , is that correct? Yes. |
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| 16:27 | . So in step four we have horizontal trajectory. Ah and no, |
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| 16:32 | of this Paralysis faces. Right. the next step, it's a big |
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| 16:39 | Falls by 20 m and high sediment . So then we've got to |
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| 16:46 | Okay, and we can sort of how much we want to race. |
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| 16:50 | just erase that amount there and I'm going to use black just for |
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| 17:01 | Um So there is. Sorry. , so we're gonna erode, |
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| 17:23 | And then some of that material is up down here. That's the eroded |
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| 17:27 | . That's your low stand. I think that was your step |
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| 17:33 | is that correct? McManus. But then the thing that Dennis didn't |
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| 17:38 | is then then what's the next step the fall? Right, so the |
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| 17:42 | level is up here, so it's go 10. So now it's going |
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| 17:45 | be down here, right, that's sea level After the fall, |
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| 17:49 | -10 m. Okay, then, then what steps do I have? |
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| 17:56 | six. The sea level rise by m under Selma supplies high. |
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| 18:05 | so sediment goes up to here. , And then we've got to put |
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| 18:11 | wedge, Arlo stand wedge in Right, So I didn't I didn't |
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| 18:16 | didn't I didn't see you did Right, So I want to I |
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| 18:20 | to see that low stand wedge in . Okay, and actually I'm gonna |
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| 18:25 | that. So at the 10 m , you're probably going to get a |
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| 18:41 | a little shorter and wedged down Okay, At the end of step |
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| 18:47 | . And then step six, we've that 10 m rise of sea |
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| 18:51 | but still settlement supply is high. , And we might get some more |
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| 18:56 | fans here. Okay, that'd be step six, I think step |
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| 19:06 | Right. And when's the big back ? Is that step six or |
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| 19:09 | I can't remember. Sorry, that's This is step. Never mind. |
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| 19:17 | , um, step six is sea rising by 10 m. Yeah, |
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| 19:22 | ? Sorry. You sure? Step , sea level rise by 20 |
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| 19:29 | And the sediment supply falls drastically. this is step five. This is |
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| 19:50 | five. Step six. And then seven, we're going to get this |
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| 19:55 | back step. Right? So 20 , that's 10:20. We're going to |
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| 20:00 | way back here and and put you the climate form there. Right? |
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| 20:06 | will be step seven. And then a You just you basically you start |
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| 20:11 | build those out again. But we're make sure you download these on the |
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| 20:17 | surface, Right? Don't have things stuck up in the air, |
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| 20:21 | This photography by gravity. That settlements to touch the lower surface, |
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| 20:25 | I'm drawing these terribly. I'm doing , But Dennis did. So don't |
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| 20:30 | bad, but dynasty that I'm doing what you did. Right? I |
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| 20:34 | trying to get you to preserve the that we start with. Okay, |
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| 20:41 | then we've got and then I think got a horizontal trajectory in there and |
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| 20:57 | I've got the last step. So you should have something looks a |
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| 21:02 | more like that. So, you did Okay, But you didn't |
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| 21:09 | this low stand wedge in here? not saying that, I think |
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| 21:13 | I think you knew something had to there, but you ended up with |
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| 21:16 | of something looked like this and then that looked like this and then kind |
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| 21:21 | a black space in here. So you've got to put that low |
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| 21:25 | in there. Right? And the only area you made is you |
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| 21:29 | very focused on using my platform. older platform has posted a new |
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| 21:35 | but what you did looked okay, , just kind of finish it |
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| 21:38 | Right, All right, Does that ? Yes. Okay, so go |
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| 21:52 | and and play with that a little , a little bit more. What |
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| 21:55 | gonna ask you to do, you , we're gonna have a long day |
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| 21:59 | is we're gonna have a few Okay, A lot of time. |
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| 22:04 | would have you working, it might walking around, you know, that's |
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| 22:08 | we're doing now, I'm asking you share making some course corrections so |
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| 22:12 | you know, if it doesn't look great, You know, I'll show |
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| 22:15 | show you the example again. And I would say over lunch, work |
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| 22:19 | work him up a little bit you know, Mcdonald's and you were |
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| 22:23 | to get the whole thing done. know how much time you spent on |
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| 22:25 | , but you know, it doesn't that long distance steps for me |
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| 22:30 | obviously. But you know, you made some good progress, have another |
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| 22:34 | at lunch. And then after lunch review your progress again and see if |
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| 22:39 | look at look a bit improved, ? But the idea is to get |
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| 22:42 | on everything right, You know, will, will course correct your work |
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| 22:46 | you get it right? There's no don't really want want you to hand |
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| 22:48 | in. That's not right. I'd you get it right working on it |
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| 22:51 | me. And so when you hand in, I'm already pretty, pretty |
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| 22:55 | . And these first exercises in many the most crucial then you can get |
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| 23:00 | ones right. You know, when start to get the data gets a |
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| 23:03 | more complicated. But, uh, , but you're all making a good |
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| 23:07 | . But so work on that a bit more maybe over lunch. |
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| 23:11 | And I think on that note, go to some lectures sound again or |
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| 23:17 | any questions about the exercise, what just done? Yeah, nope. |
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| 23:28 | hmm. All right. You're all the big slide. Okay. |
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| 24:04 | So what I'm going to do this , we've got some lectures to get |
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| 24:08 | . So I want to give you little bit of a review of traditional |
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| 24:13 | graffiti kind of give you an idea sort of the overall field of photography |
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| 24:17 | then we'll talk about where sequence photography in. So I'll go through some |
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| 24:23 | strata graphic definitions and concepts and perhaps some of you this may be review |
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| 24:29 | material that you would have learned as undergraduate Madonna. We we understand that |
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| 24:33 | of your more engineering background. Some this may be a bit newer. |
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| 24:38 | So it'll be a good introduction for and a good review for everybody |
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| 24:43 | We'll talk about some of the Oldest of 16th century concepts of strategic graffiti |
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| 24:50 | . And then I really, I to talk a bit about this |
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| 24:54 | informal and formal strata graphic schemes and photography is something that most people consider |
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| 25:02 | of boring. It's a bookkeeping. , I'm just gonna make, I'll |
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| 25:10 | one big, big overarching statement most the geology of the world. The |
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| 25:19 | were named based on very traditional with strata graphic principles. I've traveled to |
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| 25:27 | countries And many, many countries. just pick on Saudi Arabia for |
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| 25:33 | They have their very formal lithography, and there's a lot of terra geologists |
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| 25:38 | very tied to that and it doesn't , it doesn't work to define |
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| 25:44 | So pairs, but nevertheless much of historical strategic graffiti of formations they have |
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| 25:51 | mapped starting From the end of the century and today are mapped in defined |
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| 25:57 | these mythos strata, graphic principles that embodied in books like the International strata |
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| 26:04 | Guide and the North American Commission on graphic nomenclature. What that means when |
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| 26:10 | actually working as a professional geologist and starts saying, oh this formation and |
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| 26:16 | formation, 90% of the time they're about traditional lithography photography. Okay. |
|
| 26:26 | you know, the your businesses decided doesn't work very well. But despite |
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| 26:31 | and there are there are some but I've been told this by professional |
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| 26:36 | photographers, sometimes the definition of reserves based on formal literature, photography. |
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| 26:43 | oil is in this formation, not formation. And you'll get a feeling |
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| 26:48 | when the course finishes as to how sequence photography is from these formal literacy |
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| 26:55 | but it's really important to understand a of the work that I do is |
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| 26:59 | around the world telling people stop using strategy graffiti, it's not going to |
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| 27:03 | you where you need to to define reservoir ceo pairs. Okay. And |
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| 27:08 | this lecture is going to give you little bit of background to help you |
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| 27:11 | what little photography is. And then we start getting into sequence photography, |
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| 27:16 | you'll realize um uh why it's different there are also other tools that are |
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| 27:23 | in photography in general, such as photography, which is the use of |
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| 27:29 | to date rocks also, we have geological timescale. And uh and uh |
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| 27:36 | and because the worst, the world's field has switched. You can also |
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| 27:41 | rocks on the basis of their magnetic . Okay, so what is |
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| 27:48 | So here's a photograph of the Grand and strategic graffiti is the study of |
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| 27:52 | large scale layering of sedimentary rocks. photography is based on the mythological or |
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| 28:00 | physical properties of the rock. Are stand stone shales, lime stones. |
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| 28:04 | their paleontological characteristics? What kind of do they have? Are those fossils |
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| 28:11 | of the age of the rock you should know from your undergraduate earth |
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| 28:18 | The trilobite went extinct at the end the paleozoic era. The dinosaurs went |
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| 28:24 | at the end of the Mesozoic So if you find rocks of |
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| 28:28 | they have to be paleozoic in And if you find rocks with dinosaur |
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| 28:32 | , they have to be Mesozoic. of course younger fossils don't have |
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| 28:36 | you know, Seneca rocks have neither nor dinosaurs in them. Mm |
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| 28:43 | And of course photography is also based designation of rocks by their age and |
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| 28:49 | by their geographic position and their So where and how they map |
|
| 28:56 | So for example, here's back to photograph of the Grand Canyon here at |
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| 29:01 | base. You've got the Grand Canyon . So these are these tilted rocks |
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| 29:06 | they're overlaying with an angular in conformity the younger paleozoic rocks starting with the |
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| 29:12 | to peat sandstone and then the rest the paleozoic succession ending in the permian |
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| 29:18 | limestone because each of these formations represents lethality. Sandstone, shale and limestone |
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| 29:28 | given a name. So that to sandstone, the bright angel shale, |
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| 29:32 | is a slope forming unit. And units can be traced around the rim |
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| 29:36 | the Grand Canyon and mapped onto geological . So let's talk about some of |
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| 29:45 | very basic principles. Nicolas Nicolas it was a danish uh clergyman. |
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| 29:56 | name was actually Niels Stenson but his ization was Nicolas steno and he was |
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| 30:04 | renowned an animist. So a classic man. He was an anonymous, |
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| 30:10 | we studied modern animals like to dissect and name all the parts. And |
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| 30:16 | also wrote a book called the Pro that was focused on trying to understand |
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| 30:21 | solids are contained within solids. There two things he looked at. One |
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| 30:27 | the observation of crystals within rocks in igneous rocks. So he would notice |
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| 30:35 | of feldspar and courts and in igneous . And he said, well how |
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| 30:40 | you get a crystal within the crystal some point? Something had to be |
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| 30:44 | . So he developed some of the that igneous rocks were produced by the |
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| 30:50 | cooling of magma. In his it wasn't understood that fossils are actually |
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| 30:58 | remains of dead organisms. They thought they're formed by modifying processes in the |
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| 31:04 | realm that provides symmetries with the with with the biological realm. But steno |
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| 31:12 | these sharp these fossil teeth in And he said, well, maybe |
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| 31:19 | those are actually shark's teeth. And they are, that meant they had |
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| 31:23 | be the product of a shark that the flesh of the shark putrefied. |
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| 31:27 | only thing that's left over is the tooth. And for the sharp tooth |
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| 31:31 | get into a Sandstone, the Sandstone to be sand. At one it |
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| 31:36 | to be in a liquid or fluid . So he recognized that originally the |
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| 31:43 | tooth was deposited sediment. The sediment then compacted and over land by younger |
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| 31:51 | that trapped the shark's tooth in the of sand. Over time, the |
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| 31:56 | was compressed to make sandstone. he also said originally these layers were |
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| 32:03 | as flat layers. His first law the law of truth position, which |
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| 32:07 | says that the layers on top are after the layers on the bottom. |
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| 32:13 | no words, the oldest layers on bottom and the younger layers on |
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| 32:17 | he said, even though sedimentary layers be folded originally there, deposited approximately |
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| 32:24 | . And he says, nowadays, might find the shocks the shark fossil |
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| 32:29 | the banks of a river in a valley, but the layers are now |
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| 32:33 | were originally continuous. Now, these may seem pretty obvious to you. |
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| 32:40 | know if we go back to the Canyon, we know that the deep |
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| 32:43 | sandstone originally covered this entire area because Colorado colorado River has cut down as |
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| 32:50 | Colorado Plateau lifted up to cut the Canyon eroded away once continuous layers. |
|
| 32:56 | , for example, here in the the slide here, you know, |
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| 33:02 | know that the repeat sandstone originally covered area, right? We know that |
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| 33:08 | Grand Canyon group originally lay across the area and these layers were originally |
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| 33:15 | Right? So we can reconstruct the before the Colorado River cut the |
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| 33:20 | Right. And as geologists, we know, although the layers of discontinues |
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| 33:26 | , they originally continues across the area that seems like a pretty obvious rule |
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| 33:31 | us, it wasn't so obvious instead his time. So he came up |
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| 33:34 | these very basic laws that allow us produce the order in which sedimentary layers |
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| 33:40 | deposited and deformed. Okay, so standards laws are are are younger layers |
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| 33:49 | lie above all the layers folded layers horizontal. That's his law of original |
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| 33:55 | . Itty and eroded layers were originally . Okay, And we still use |
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| 34:01 | layers today in interpreting sequence photography, we if we see an incised valley |
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| 34:06 | filled up, we assume that the cut into layers that originally continuous and |
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| 34:11 | now produced an un conformity. So one of the things that we're |
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| 34:19 | trying to figure out as geologists is correlates with what? Okay, so |
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| 34:23 | is the Grand staircase in in western America, you know. And interestingly |
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| 34:30 | you go to the Grand Canyon near top are these cross bedded sandstone of |
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| 34:35 | age of the Coconino sandstone. If go up to moab and arches, |
|
| 34:40 | see the cross bedded sandstone of the and they're both formed in a desert |
|
| 34:46 | the Sahara. Now the Coconino is age and the Navajo is Jurassic in |
|
| 34:53 | . They're both formed in very similar . They both look very similar, |
|
| 34:58 | similar deposition environments, but very, different in age because at different times |
|
| 35:03 | America had desserts and other times there no desserts and the dessert's came back |
|
| 35:08 | . You have cycles of desert But if you, if you correlate |
|
| 35:14 | layers over hundreds of kilometers, you that the Navajo sandstone is separated by |
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| 35:20 | different formations from the older Coconino And so you realize that although they |
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| 35:25 | the same, that they're the same faces, there are different age. |
|
| 35:30 | have different fossil contents and they're not same at all. And of course |
|
| 35:34 | Navajo, although it's not very false if you found fossils, you find |
|
| 35:39 | of course the Coconino which is permian might have and does have lizard tracks |
|
| 35:44 | it. But there were no dinosaurs the permian. So the fossil content |
|
| 35:48 | be very different. Mm hmm. so look at this terrible spelling here |
|
| 35:56 | can be within a region of the or between continents. And you |
|
| 36:02 | we come and use fossil content to how units curling. Okay, so |
|
| 36:08 | a photograph of of the layers from Grand Canyon and there's the layers just |
|
| 36:14 | arches National Park. And in both , you have these nice, nice |
|
| 36:18 | forming uh cross bedded units. But I said, they're very different |
|
| 36:25 | Okay. You can physically correlate rocks one place to another if they're |
|
| 36:31 | Ah And you can do that in place like the Grand Canyon where you |
|
| 36:34 | physically just walk the layers out or them out. And if you if |
|
| 36:38 | if you stand on one edge of Grand Canyon, you can see the |
|
| 36:41 | across the other side with a pair binoculars. You could, you could |
|
| 36:45 | them pretty easily with it with a of binoculars. Of course a lot |
|
| 36:49 | time here in Hambleton we have the escarpment, which is the exposure of |
|
| 36:53 | Panasonic lime stones that formed in the period. But of course sometimes they |
|
| 36:58 | nice cliffs and other times the cliffs covered with vegetation but you can still |
|
| 37:04 | the cliff even though it's covered by . And the assumption is, oh |
|
| 37:08 | , even though there's some trees over cliff, the geology under the vegetation |
|
| 37:11 | the same. Okay. And so are good at sort of trying to |
|
| 37:15 | what the geology is underneath the vegetation areas unlike the Southwest US which are |
|
| 37:22 | and have very, very nice That's not always the case. Um |
|
| 37:29 | and you know, you can also by looking at the similarity of rock |
|
| 37:33 | . The problem with that is is I, as I talked about with |
|
| 37:43 | , with with the Grand Canyon versus , similar looking rock types. Alien |
|
| 37:49 | bedding can be very different ages. have to be careful. You don't |
|
| 37:53 | say, oh, the same mythology be the same age. Okay. |
|
| 37:57 | is an example of two measured Okay, One is uh closer to |
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| 38:03 | River, it's the Green River Okay. And then uh west water |
|
| 38:08 | out towards Grand Junction and you can , you can see there's the the |
|
| 38:13 | Cambrian basement. That'd be the same the vishnu schist. That's the basis |
|
| 38:17 | Grand Canyon in this case that's overlooked the mod Kobe formation. That doesn't |
|
| 38:23 | make it to Westwater. The chin . Wingate a continuous, the Navajo |
|
| 38:28 | out and so on and so Okay, the macro shell is the |
|
| 38:33 | seaway. That's that's the rocks that primarily work on for a living and |
|
| 38:37 | the way extended from Green River, the way to Grand Junction and all |
|
| 38:41 | way to uh all the way to and beyond. Okay, so correlation |
|
| 38:47 | matching the same age straight up between places. Okay, sometimes you can |
|
| 38:53 | it out. Sometimes you can look the order formations and match them up |
|
| 38:58 | the paleontology and the other information you . Okay, here's a very simple |
|
| 39:05 | . Again, these are all from your textbook. So this is sort |
|
| 39:08 | a bit of a review. So we have a section A and here |
|
| 39:16 | have section B. So my point a bit skittish here. Section |
|
| 39:36 | And section me. Okay. And section air we've got um what do |
|
| 39:42 | have here? Crawl a bite an trial abate another trailer bait. Maybe |
|
| 39:50 | these then that's sort of lame by with rocket pods. Kerala bites gastro |
|
| 40:01 | and that's over land by that the had. That's a bracket pod. |
|
| 40:07 | gastro pod, Unit five has a for corals, colonial corals, Then |
|
| 40:18 | over nine by Unit six. That's a couple of ammonites And a couple |
|
| 40:22 | five outs. Okay, so each these layers, layer 12345 and six |
|
| 40:28 | layers of different mythologies with different Okay, over in section A. |
|
| 40:35 | see that layer one is present but tilted. Okay, so it's been |
|
| 40:41 | . Layer two is president and and three is present. Layer, layer |
|
| 40:45 | is missing in section A. And A. If we actually draw a |
|
| 40:51 | line there, we'll see that layer six directly overlying layers too. |
|
| 40:58 | layers are missing. Mm hmm And 5. Exactly. Right. |
|
| 41:05 | , no, 34 and five are you missed one. Right. And |
|
| 41:08 | that of course defines an un Now Angela, can you tell me |
|
| 41:13 | kind of a nonconformity this is going to your first year geology that different |
|
| 41:21 | of un conformity is in angular on . Exactly correct. That's an angular |
|
| 41:30 | conformity. Okay. And of course six is continuous across the area. |
|
| 41:36 | seven is present in section a but either eroded or was never deposited in |
|
| 41:41 | B. Okay. So in this we're using the integration of fossils and |
|
| 41:47 | to correlate the different areas and we that that that you know, it |
|
| 41:52 | like we've got a conglomerate lag there forms in angular and conformity that separates |
|
| 41:58 | tilted rocks of layers 123 and four the flat lying layers of of units |
|
| 42:04 | and seven. Okay, now there many different types of photography. |
|
| 42:14 | here here's here is a list. , we've got little photography allows photography |
|
| 42:22 | photography which includes genetic and de positional photography. Then the right, we've |
|
| 42:28 | bio strategic graffiti, Chronos photography, , photography, magneto Stratan graffiti, |
|
| 42:35 | does photography, event photography and more photography. Now, these are the |
|
| 42:40 | schemes. So these are the things you'll find in the North american Commission |
|
| 42:45 | strata. Graphic nomenclature and the international Graphic guide. These are informal. |
|
| 42:54 | none of these photography's you will you in the North american Commission strata Graphic |
|
| 43:01 | or in the International strata Graphic Okay. You will find sequence photography |
|
| 43:08 | it used to be in the International Graphic Guide. Okay. Uh, |
|
| 43:16 | the only word that ever made it there was a thing called the symptom |
|
| 43:22 | has fallen out of disuse. But sequence photography remains an informal sequences |
|
| 43:30 | informal photography and so that you might the question, why are we doing |
|
| 43:34 | class on something that's not even recognized a formally accepted legal strata graphic |
|
| 43:41 | Right. And the short answer is it's useful. So I want us |
|
| 43:50 | go back in time a little Okay. And imagine that we're back |
|
| 43:56 | that The 18th century. So, know, it's 1873 and you |
|
| 44:03 | you're working for the very first version the whatever the United States Geological Survey |
|
| 44:09 | or you know, wherever you might or if you're in India maybe back |
|
| 44:13 | those days, you'd be working for India british Geological Survey mapping formations in |
|
| 44:19 | Himalayas to right or wherever you might . And or if you're in |
|
| 44:26 | you might work for the, you , the Canadian Geological Survey. So |
|
| 44:31 | we, here we have a group geologists in Utah and there's a shale |
|
| 44:38 | and then there's a sand formations draw measured section, right? There's a |
|
| 44:44 | , there's a sand and the shale called the tonic shale and the sandstone |
|
| 44:49 | called the Fair and sandstone. The contact is pretty, pretty easy |
|
| 44:54 | pick. Now you may notice that know that the the tunnel is |
|
| 45:02 | but you can still see ridges of in it and the fairness sandy, |
|
| 45:06 | there's also layers of shale in So, you know, you you |
|
| 45:11 | , you sort of stand back and can all pick that basic contact between |
|
| 45:14 | sandstone and shale, but you do that there are that the shales contain |
|
| 45:19 | sand stones and the sand stones contain shales. Right? So it's not |
|
| 45:24 | absolutely razor sharp contact, but little graphic unit such as formations are |
|
| 45:32 | defined on the basis of the mythological . Okay, And in our |
|
| 45:40 | you know, these are the little , graphic units or formations in the |
|
| 45:44 | Canyon and they have a formal name Pete's and then a little ology |
|
| 45:50 | a formal name that the mov or and then a with ology, the |
|
| 45:57 | , the Red wall is the formal and it's a limestone and so on |
|
| 46:01 | so forth. The hermit shale, coconino sandstone, sometimes a Torah week |
|
| 46:08 | and that would apply. The Tory has more than one mythology in |
|
| 46:11 | So it's neither a sandstone or it's a unit of mixed pathologies and |
|
| 46:17 | it forms a slope. Okay, sometimes formal formal uh sometimes it'll be |
|
| 46:27 | fair and sand stones, Sometimes it'll a fair and formation of the fair |
|
| 46:30 | member depending on where you are in hierarchy. Almost all strategic graffiti are |
|
| 46:37 | . Almost all strategic these are That means you have uh small units |
|
| 46:44 | large units. Okay. In terms Lithuania, strategic graffiti. Okay, |
|
| 46:51 | formation is the basic fundamental unit of . Okay, if you're mapping and |
|
| 46:59 | strata, graphic units, you are by the strata, graphic police of |
|
| 47:04 | world to define formations, you may to lump formations into groups that you're |
|
| 47:11 | required. You may wish to subdivide and members, it's not required. |
|
| 47:17 | , You are required. You can't a member that's not part of a |
|
| 47:23 | . You can't have a group that subdivided into formations. You can have |
|
| 47:28 | that aren't members of groups and you and you you're welcome to have formations |
|
| 47:33 | that that don't have members within Does that make sense? You |
|
| 47:41 | sometimes I'll put that in the What's the basic fundamental unit of little |
|
| 47:46 | ? And although members are smaller, don't you're not they're not required to |
|
| 47:51 | defined. So the formation is the fundamental unit of of mapping and strategic |
|
| 47:58 | . And if you're doing fieldwork, must define formations. Okay, so |
|
| 48:04 | kind of a critical point. Neither or members are required nor beds. |
|
| 48:08 | sometimes they'll be defined defined in areas sometimes you can have super groups. |
|
| 48:15 | so you can sort of build up little bit. Now. Little photography |
|
| 48:21 | in the North american Commission of Graphic normal nature. Okay. And |
|
| 48:27 | can find that on the web. will be an A. P. |
|
| 48:29 | . Data pages somewhere. And it's traditional scheme for formally naming rock units |
|
| 48:36 | on the basis of mythology distribution age , graphic position typically as defined and |
|
| 48:44 | sections. So you measure a bunch layers from top to bottom and you'll |
|
| 48:48 | oh the you know the kaibab limestone younger than the redwall limestone in vertical |
|
| 48:57 | . And what's interesting is the formation defined as the fundamental unit of |
|
| 49:04 | right. And the concept of map is something that's not well addressed in |
|
| 49:12 | opinion the literature although it's a very old concept and the idea of making |
|
| 49:18 | map um Is again a very old now. How many how many of |
|
| 49:28 | have done a field methods or a camp? I have. Yeah. |
|
| 49:34 | . Have you done as well? I didn't do anything. Angela. |
|
| 49:42 | about you if you're gonna field like camp or field methods, undergraduates? |
|
| 49:50 | I was in the same class with . So we got the opportunity to |
|
| 49:53 | to Big Ben in west texas Right? Geographic geologic mapping as well |
|
| 49:59 | structural geology. So we did a of food work over there. Yeah |
|
| 50:03 | so describe the process. Right? make a map and then what do |
|
| 50:07 | do you make a map? We strikes and dips. You dip is |
|
| 50:14 | to relate the sedimentary strata. We determine the thickness of the depression measuring |
|
| 50:22 | in the field. And after that didn't work that much with fossils. |
|
| 50:27 | just did a lot of structural And you made a cross section |
|
| 50:33 | Based on your map. So, , so the concept of math ability |
|
| 50:43 | defined long before there was seismic data a lot of well logs scoring. |
|
| 50:50 | , you know, in the old literally, you know, the the |
|
| 50:53 | survey geologists were mapping their countries. would typically go out on horseback and |
|
| 50:59 | would do exactly what Mcdonald's has Look at the surface geology, take |
|
| 51:04 | and dips and then, you based on your map, You |
|
| 51:08 | you might have a contact, you , a formation 1, 2 and |
|
| 51:13 | . You know, maybe you've you know, the units dipping in |
|
| 51:16 | geometry. And then based on, know, the scale of the |
|
| 51:21 | Let's say that's 10 km right. you would draw a cross section at |
|
| 51:31 | prime. So there's your cross section you know, let's say that the |
|
| 51:38 | and let's just say for grins, parallel to the strikes and dips. |
|
| 51:43 | the that the contours are increasing in in that direction. So you do |
|
| 51:47 | topographic map and you have a series layers that dip or whatever the the |
|
| 51:54 | of the that you determine from your strikes and dips, right? Let's |
|
| 51:58 | these dip at, you know, degrees, let's say right to the |
|
| 52:04 | . And so you end up making dip a cross section. Okay, |
|
| 52:10 | very different than what we do in patrolling business. We start with the |
|
| 52:15 | section because we've got we have vertical . Right? And and typically that |
|
| 52:21 | hard part in subsurface judges making a mapping the reservoir, sand stones or |
|
| 52:27 | the structure. Right? So typically start with the map, you start |
|
| 52:32 | the cross section and patrolling geology and have to make a map. Whereas |
|
| 52:36 | field geology you start with the map then you have to make the cross |
|
| 52:40 | by projecting the layers of the subsurface . Dennis described, he did when |
|
| 52:45 | was doing his undergraduate fieldwork. Is fair enough, Dennis? Yes, |
|
| 52:53 | . So here's a map that will give to uh students and their PhD |
|
| 52:59 | exams and just ask them some Right? So here's a map of |
|
| 53:03 | and I just show up because it a major petroleum province and it's where |
|
| 53:07 | cut my teeth in terms of, know, first province, I worked |
|
| 53:12 | as a geologist essentially. And so ability, you know, up until |
|
| 53:18 | know about 7 1940s. So you , prior to World War II, |
|
| 53:24 | you know the World War ton World , there was still a lot of |
|
| 53:29 | were fighting using horseback, Gasoline was fairly new. Not that it wasn't |
|
| 53:36 | used. I mean, you the oil business kind of started in |
|
| 53:39 | , but a lot of that was, was for kerosene that was |
|
| 53:43 | to replace whale oil lamps because whales being hunted to extinction. And so |
|
| 53:49 | Lamps replaced whale oil lamps in the . But you know, Henry Ford |
|
| 53:55 | around 19, invented the automobile and the 1940s, you know, at |
|
| 54:01 | eve of the Second World War, , that became very much a gasoline |
|
| 54:07 | . Right? When Churchill made the decision to convert the british Navy from |
|
| 54:12 | to diesel, it was a big for him, Britain had lots of |
|
| 54:17 | deposits, but cole was a very fuel to transport. It was |
|
| 54:22 | it was dirty and you couldn't go far Diesel was much more efficient. |
|
| 54:28 | when he converted the british navy to to gasoline, the, the advantage |
|
| 54:35 | speed. The disadvantages, they were all their gasoline from the americans and |
|
| 54:41 | the nazis tried to cut off their with their diesel driven U boats, |
|
| 54:46 | created a lot of problems for the . Right? So World War Two |
|
| 54:51 | very much a gasoline driven World Right? And of course at the |
|
| 54:55 | of the World War II, the and the exploration for petroleum exploded as |
|
| 55:01 | became more and more dependent on on fossil fuels, gasoline in particular. |
|
| 55:08 | prior to that mapping was was done horseback walking across the surface of the |
|
| 55:14 | and mapping the various units and the . And, you know, Back |
|
| 55:18 | in the late 70s when I was undergraduate, a lot of mapping was |
|
| 55:24 | in Canada because, you know, to map the mineral resources and all |
|
| 55:28 | mapping was done at 1 : 25001 50,100,000 scales. They have a topographic |
|
| 55:35 | , go map the area. And mapping was definitely based on outcrop |
|
| 55:41 | So here's a map of the province Alberta. You can't see the scale |
|
| 55:47 | , but, you know, it's big province, it's something like 1000 |
|
| 55:54 | from north to south and you five or 6, miles across, |
|
| 55:59 | a bit more take today to to across Alberto. And so what we |
|
| 56:05 | is, is in the in the , we see these areas hundreds of |
|
| 56:10 | kilometers of areas covered by the same type. Okay. And of |
|
| 56:15 | you know, you should understand if seeing a layer that's covering hundreds of |
|
| 56:20 | of worth tens of thousands of square , that's probably a pretty flat |
|
| 56:26 | Okay, then we get into the Mountains and we see linear bands of |
|
| 56:33 | . Those rocks are also almost certainly . Okay, so that line defines |
|
| 56:39 | boundary between the tilted deformed rocky mountains the under formed great plains. Of |
|
| 56:45 | , you know, if you drill that yellow unit here, you'll encounter |
|
| 56:49 | purple and the brown and the green which extends all the way back to |
|
| 56:52 | rocky mountain thrust front. Okay. of course the Alberta basin is rich |
|
| 56:59 | oil and gas deposits. So math in the days. So here, |
|
| 57:07 | example, we can see cliff forming , slope forming units, cliff forming |
|
| 57:12 | and slope forming units in general. know, if I draw my if |
|
| 57:26 | was going to draw my photography, have sandstone, a shale, |
|
| 57:35 | shale may be thinner sandstone and sandstone shells that maybe there's a sandstone |
|
| 57:42 | here. So, you know the exposed the various sandstone and shales. |
|
| 57:49 | . From the contour map, if draw a topographic map. So those |
|
| 57:54 | my topographic contours, that might be m elevation, That might be 20 |
|
| 58:01 | elevation. Okay. And of course cliff forming units, basically the contours |
|
| 58:07 | very tight together and the slope forming will be the contours a bit further |
|
| 58:11 | . So it's actually difficult to map cliffs on a plan view map, |
|
| 58:16 | , because they don't occupy a lot space on the map, for |
|
| 58:20 | here's the Grand Canyon again. and you can see that that the |
|
| 58:26 | cliffs from very very narrow units on map. Okay, The carbonates, |
|
| 58:32 | covers the whole area. But that's cliff, that's the that's the top |
|
| 58:36 | the cliff. So that's basically As soon as you drop in the |
|
| 58:40 | Canyon, what you see is very bands represent that little part of the |
|
| 58:46 | that represents the intersection of the exposed and the surface of the earth. |
|
| 58:52 | ? And then the bottom you get rocks exposed at the base of the |
|
| 58:55 | Canyon, so very thick cliff forming that could be very thick. They |
|
| 59:01 | a narrow region on a plan view . Mm hmm. So here's a |
|
| 59:09 | Strattera graphic cross section of my PhD . This is the Dunvegan formation. |
|
| 59:17 | talk about this in quite a lot detail in a separate lecture. |
|
| 59:22 | one of the questions is how do define how do you define this? |
|
| 59:27 | do you use to map the structural of this formation? Okay, so |
|
| 59:33 | an example of an ice pack So there's the basis Dunvegan here, |
|
| 59:43 | the base there, there's the base , there's the base there, that's |
|
| 59:48 | end of it. From the top somewhere in here, there's a little |
|
| 59:52 | line here. So that's the Dunvegan in terms of literature photography and obviously |
|
| 60:10 | this point, the Dunvegan is no present, right. It's all pinched |
|
| 60:14 | into shale. Now, I could a structure map on the base, |
|
| 60:18 | is a shoes online, which means Dia Cronus, the age of the |
|
| 60:22 | is different, different places. I make a structure map on the |
|
| 60:28 | but even there, there's a little there. Okay, I could also |
|
| 60:34 | a map of the ice a so it's thick hair and it goes |
|
| 60:38 | a zero edge there. So there's ice a pack right? Going from |
|
| 60:43 | to thin, right? So it's out in that direction. So that's |
|
| 60:48 | if I if I do a cross a to a prime, right? |
|
| 60:54 | Dunvegan sort of looks like this a a prime, so it's thicker And |
|
| 61:04 | it pinches out to a zero Now, if I look at the |
|
| 61:08 | geology, okay, the formation is tilted towards the thrust front. |
|
| 61:14 | so it's high here and it's more buried back there. Okay. And |
|
| 61:19 | dip on the top of the formations shots, one degree. Okay, |
|
| 61:24 | that's a structure map on the top the Dunvegan. So that's that's this |
|
| 61:30 | there. Okay. Now, regardless whether now there's also this K1 market |
|
| 61:37 | , that's a timeline, a little , the well on that I think |
|
| 61:41 | a timeline and that dash line is parallel to the top of the |
|
| 61:49 | it does diverge just a little bit a few meters but probably enough not |
|
| 61:55 | to drastically change that dip angle, ? So the little strata, graphic |
|
| 62:03 | departs from the timeline ah By about m 100 km. So that's a |
|
| 62:11 | departure of .03° vs structural different .89°. , one of the questions that, |
|
| 62:18 | that make any difference if you were looking for some subtle structural traps to |
|
| 62:25 | oil in the Dunvegan formation? The is probably not, but it |
|
| 62:29 | it could be right. So just that, that that if you map |
|
| 62:34 | literature, photography versus sequence photography, may get a slight difference in the |
|
| 62:40 | or the structural geology of the You're mapping. It would be more |
|
| 62:44 | for the base because the base is diaphanous than the top. Okay, |
|
| 62:50 | know, interestingly, the Dunvegan is delta. Here's an example of an |
|
| 62:56 | lift map of one of the So these would be one of the |
|
| 63:00 | ceo pairs And the structural depth again about 1° towards the southwest. |
|
| 63:09 | That the Dunvegan builds from north west south, so it programs in that |
|
| 63:15 | and then here we have a lateral out where the sides of the rivers |
|
| 63:19 | deltas are pitching out up structural Okay, so anytime you get a |
|
| 63:27 | a a lateral protrusion of a sandstone as here here and here. Those |
|
| 63:35 | potential strata, graphics slash structural And indeed, the Dunvegan has a |
|
| 63:41 | of very small isolated oil fields that the subtle strata, graphic structural |
|
| 63:50 | any oil that enters into the Dunvegan can spill out through that major and |
|
| 63:57 | valley there. So it's difficult because of the relations between the structural geology |
|
| 64:04 | the strata, graphic relationships, it's to produce a good structural trap in |
|
| 64:10 | particular formation. That makes challenging to for oil and gas in this formation |
|
| 64:16 | extremely detailed maps of the reservoir sand to find those subtle structural traps And |
|
| 64:25 | , you've got to integrate this particular correctly to explore for that unit. |
|
| 64:34 | , next up we'll talk about bios . So Bart photography is the formal |
|
| 64:39 | graphics scheme to find the basis of and formal successions. Okay. And |
|
| 64:47 | typically define bio zones. So here's example of, you know the fossil |
|
| 64:53 | of the great eras the scene azotic which means new life. Mesozoic which |
|
| 64:58 | middle life for middle middle animals and our paleo means ancient. So ancient |
|
| 65:04 | , what is the paleozoic era? , of course these the periods the |
|
| 65:10 | era, the Cambrian order mission celery devonian. Carbon efficient premium blend into |
|
| 65:15 | Triassic Jurassic and cretaceous of the Mesozoic . And of course now we've got |
|
| 65:22 | what do you have the gene, neo gene. This is an old |
|
| 65:26 | and we used to still use the returner. We don't use it as |
|
| 65:28 | anymore. And of course there's our trilobites, they went extinct at the |
|
| 65:33 | of paleozoic. Okay, so if find trilobites, their diagnostic of the |
|
| 65:38 | the paleozoic and of course there was big extinction at the end of the |
|
| 65:43 | and the trilobites were much less prevalent the carboniferous permian versus the slurry into |
|
| 65:51 | . Okay. A lot of bracketology extinct also at the end of |
|
| 65:54 | So it but some squeaked through and on and so forth. Now, |
|
| 66:01 | we look at a spin diagram, is for the broccoli pods. |
|
| 66:06 | Um and what it shows is that was, you know, that that |
|
| 66:11 | at the camera explosion there was a diversification of bracket pods. Then there |
|
| 66:17 | the the great automation biological diversity a huge expansion of the diversity of |
|
| 66:24 | pollens. And these are these are . Remember the the classification of life |
|
| 66:31 | earth. You got domains, classes, families, orders, |
|
| 66:38 | families, genus and species. The is sort of a lower level |
|
| 66:42 | not grouping. And you see that the paleozoic, you know, the |
|
| 66:49 | bracket pods are pretty diverse. You , there's some increases and decreases then |
|
| 66:54 | the end of the permian period there a mass extinction and the bracket pods |
|
| 66:59 | quite recovered. Yes, there are pods alive today in the oceans, |
|
| 67:04 | they're much less diverse than they were the proposal. And then if we |
|
| 67:09 | at some of these groups more we find for example that the overloaded |
|
| 67:14 | pods are confined to the early The bottom rigs range from late Cambrian |
|
| 67:22 | devonian. The periphery rinse from mid division too early Jurassic. Okay, |
|
| 67:31 | I would like you to give me hands up. Which of you students |
|
| 67:36 | identify the difference between an overloaded bracket and as peripheral. How many of |
|
| 67:44 | could even identify the difference between a pod and a bivalve. Angela. |
|
| 67:53 | screwing your face up. That means I know between rocket pods and |
|
| 68:00 | Rocket pods have like the hinges actually than the bracket under backgrounds. |
|
| 68:07 | And the and the symmetry is Anyway, the point being is |
|
| 68:12 | you know those of us who have an undergraduate course in paleontology, we |
|
| 68:18 | have learned how to distinguish bracket pod a bivalve. But at some |
|
| 68:24 | depending on your paleo class, you were introduced to some of the bracket |
|
| 68:28 | , but unless you're a professional you're probably not going to remember that |
|
| 68:32 | . Okay, so in the oil by and large working joes don't do |
|
| 68:38 | photography. That work is done by by photographers like Don Van neumann |
|
| 68:45 | Okay. And of course, one the courses that that those of you |
|
| 68:49 | the geology program will take is Don noon noon houses, He has an |
|
| 68:54 | course on bio strategic graffiti Madonna fula track. You probably won't take that |
|
| 69:01 | . Okay. And so here's an of the kind of of data that |
|
| 69:06 | photographers use. So what we have so this is well data. So |
|
| 69:12 | got the depth of the well on vertical axis on the horizontal axis would |
|
| 69:20 | . So this is the, so is neo gene data. Okay. |
|
| 69:24 | that would be um late late santa's . And these represent the fossils on |
|
| 69:31 | horizontal axis and they're organized according basically their age. Okay. And this |
|
| 69:38 | a last appearance datum. So what shows. So the green represents the |
|
| 69:45 | of microfossils in the samples for well of these samples are from the chip |
|
| 69:51 | as opposed to cores. Okay, the older fossils are to the |
|
| 69:58 | younger fossils are to the left. it shows that these oldest fossils here |
|
| 70:04 | present only in the bottom of the and none of them are found in |
|
| 70:08 | in the higher depths. These fossils a bit younger and so they cluster |
|
| 70:14 | know in these depths here and you see that that so these would represent |
|
| 70:19 | the the horizons above which these false aren't present anymore. So the assumption |
|
| 70:25 | they're extinct above that point. So what you're looking at is an extinction |
|
| 70:31 | product on the right. We have different series of fossils again with the |
|
| 70:39 | on the right and the youngest on left. Okay. And this represents |
|
| 70:44 | first appearance state. Um Okay, these are the youngest fossils and they |
|
| 70:50 | only in the in the higher parts the well these forces appear in the |
|
| 70:55 | parts and they and some of them appear and then they have an abundance |
|
| 71:00 | there and of course these fossils are right at the very base. |
|
| 71:05 | so this basically is a first appearance indicates the the appearance of new species |
|
| 71:11 | and large. And so you can the last parents of the species, |
|
| 71:16 | first appearance of a species and integrate . And then start comparing these with |
|
| 71:20 | known dates of these various fossils to putting together a detail of bio strategic |
|
| 71:27 | and Don Van noon house. We'll about this in much more detail |
|
| 71:31 | this is your audience. I I think you're the only geophysics |
|
| 71:35 | Right, so this may be the information you get about bios, |
|
| 71:39 | No, I'm sorry. I'm a engineering graduate. Magna Hellas is the |
|
| 71:45 | major. Okay, okay, Well anyway, I'm never gonna get |
|
| 71:50 | right. Just keep reminding me. a bi zone can be defined on |
|
| 71:56 | range of a single fossil. so there will be a Bizot based |
|
| 72:00 | the first appearance and last appearance of given species, kate. You can |
|
| 72:05 | a bi zone that's based on, know, the top is defined by |
|
| 72:08 | by the extinction of this species and appearance of another species. For |
|
| 72:16 | you can have a bi zone that's on the extinction of that organism and |
|
| 72:20 | first appearance of this one. And that would that would be a relatively |
|
| 72:26 | interval of rock that could be a period of time. Okay. Or |
|
| 72:30 | can define a bi zone based on overlap between first appearance and last appearance |
|
| 72:35 | a variety of species. Or you define a bi zone based on the |
|
| 72:41 | of time in which there is an of a particular species. So going |
|
| 72:45 | to a plotter and say, well organisms seems to be really abundant |
|
| 72:49 | So that would be sort of an by zone. Even though the species |
|
| 72:54 | for higher and lower. You can , yeah, we're not going to |
|
| 72:57 | for the total range of the We're going to go for that period |
|
| 73:00 | time when they seem to be very . Okay. And so these are |
|
| 73:07 | the kinds of things that that buys use. Okay, so an office |
|
| 73:13 | for example is that sort of that's one here. That'd be a bi |
|
| 73:20 | based on the integration of more than fossil with both first and last appearance |
|
| 73:25 | to give you a shorter time interval correlation than if you relied on one |
|
| 73:31 | by itself. Okay. It is that, you know, species will |
|
| 73:39 | more abundant if the environments of deposition . So if you recall our our |
|
| 73:47 | . Okay, we've got cloud of . Right? And we've got faces |
|
| 73:51 | are migrating through time. Let's say have an animal that loves living just |
|
| 73:56 | the delta. Right? That animal's to migrate with the faces, whatever |
|
| 74:01 | takes. If it takes, You , 100,000 years for the environment to |
|
| 74:06 | , then the bugs will simply migrate that as that environment of deposition |
|
| 74:11 | So sometimes you find that the abundance will be die acronyms, which means |
|
| 74:16 | it's different ages in different places. that would record the fact that you've |
|
| 74:22 | the shift in environments which produces She's um line. And I'll talk |
|
| 74:27 | about what that means in a later . And here's another example of of |
|
| 74:38 | abundance peaks and actually zones. now here's another slide that I think |
|
| 74:46 | really worth looking at. Um So is the duration of individual species. |
|
| 74:53 | . So unfortunately don't have don Van houses favorite organism. He he studies |
|
| 75:02 | cards and those are little crustaceans. a little shell, they look like |
|
| 75:07 | bivalve, but they're not, they look a bit like a bivalve. |
|
| 75:10 | have two shells with a little shrimp creature living inside and they're pretty |
|
| 75:15 | They've seen a microscope to see But you know, a lot of |
|
| 75:18 | work in the oil business is done the basis of microfossils because they're they're |
|
| 75:23 | they don't get broken up when you . He was really well you extract |
|
| 75:30 | pulverized remnants of the formations you drill . And those are the cuttings or |
|
| 75:36 | or the mud trips they call them the mud chips might be about as |
|
| 75:41 | as your fingernail and a chip of the size of your fingernail is much |
|
| 75:47 | than the plankton. And foraminifera and and ah donna flatulence and other materials |
|
| 75:55 | and pollen. And so a lot oil companies use spores and pollen. |
|
| 75:59 | flatulence, which is paranal aji and of the foraminifera and sometimes ostro codes |
|
| 76:06 | get the age of the rocks. problem is a lot of those plankton |
|
| 76:11 | for long periods of time. So IQ or free floating foraminifera as benthic |
|
| 76:17 | as typically they last for 20 million or more. Okay, Marine Donna |
|
| 76:23 | 25 million years. Right. And too much time, you know. |
|
| 76:28 | that's why particularly micro paleontologists. And is a slide I got from Pierre |
|
| 76:35 | zippy. Pierre zippy was one of last uh bars photographers at atlantic Richfield |
|
| 76:42 | they got bought by BP. They went here and there and Pierre formed |
|
| 76:47 | own consulting company and he was he a pal enologist. So he had |
|
| 76:52 | deal with with long lived species. a lot of the work he did |
|
| 76:55 | kind of using these integrations of first last appearance is to use the overlap |
|
| 77:00 | durations to get much better resolution of time versus just a single duration of |
|
| 77:07 | because the single species lived too Um If we should go down, |
|
| 77:14 | know, by vows and gastro politan can have durations of, You |
|
| 77:19 | 10 millions of years. Ammonites are commonly used in the cretaceous Ah and |
|
| 77:26 | ranged from million years after about five years and duration of an individual |
|
| 77:32 | Mantles typically 1 - two million Troglodytes are pretty short lived, you |
|
| 77:41 | , little bit over a million years delights which are heavy coordinate, Very |
|
| 77:47 | for pennies, correlations to three million and so on and so forth. |
|
| 77:53 | it does point out that all these are much faster than, say, |
|
| 78:00 | lack of its climate cycles. A of what I'll talk about that a |
|
| 78:04 | of the correlations will mess around with we move forward in the class will |
|
| 78:08 | the correlation of these very high frequency cycles that define reservoir ceo pairs in |
|
| 78:15 | rocks. Okay, correct. So an example, here's a type well |
|
| 78:24 | work that I did when I worked atlantic Richfield, sorry, when I |
|
| 78:29 | doing my PhD and uh you here's a well, it's continuously |
|
| 78:35 | It was a strata graphic test well by parallel back in the 50s I |
|
| 78:39 | , or late 40s and the core shales and sand stones. Um |
|
| 78:46 | the various little strata graphically defined So there's the chefs free shale, |
|
| 78:52 | over land by the done vague information that's overlaid by the casket pal shale |
|
| 78:57 | casket power formation. Um then on left we've got the various stages got |
|
| 79:05 | Albion Cinemania. Tyrone Ian stage. those are stages or ages of |
|
| 79:11 | of the cretaceous period. Okay, obvious sentiment, sentiment, sentiment in |
|
| 79:18 | separates the upper and the lower cretaceous . Okay, and then the |
|
| 79:23 | you've got the bisons. So what show is that the dunvegan formation belongs |
|
| 79:30 | the ammo back salads, grave nori zone and the very well very well |
|
| 79:36 | . Perplexes zone by ozone. The , very melon Ortiz bio zone is |
|
| 79:42 | land by the flagellum and glad I oh, these are all based on |
|
| 79:48 | foraminifera. The environmental authorities perplexes bio is subdivided into the amazon accolades graven |
|
| 79:57 | , which is over land by the Iran insists sub zone and then the |
|
| 80:03 | gladiator by his own is divided into chapel of fraud modi's spirit tense and |
|
| 80:10 | ammo box salads. Pickles sub there's a unit with no fossils and |
|
| 80:16 | the outlet Albion is characterized by the Manitoba. NCIS sub zone. |
|
| 80:22 | I couldn't tell you the difference between van when authorities. Periklis Perplexes or |
|
| 80:28 | grave story. But these all of work was done by um charlie stelco |
|
| 80:40 | what was his name? Love a wall, I forget his first |
|
| 80:49 | , you know, but but you this this bottom is all done by |
|
| 80:52 | professional paleontologists. Now, at one , you know, people ask one |
|
| 80:57 | my PhD, did you integrate the certificates? That would know because I |
|
| 81:01 | interested in doing detailed sequence photographic work the Dunvegan formation and it belongs to |
|
| 81:06 | single buyer zone. So the bios wasn't very helpful in subdividing the formation |
|
| 81:13 | I was working on. Okay. , now, the other thing that |
|
| 81:22 | want to emphasize is that in sequence we also have, sorry, in |
|
| 81:30 | Ashley. So I'm losing my thread . That's my my brain is is |
|
| 81:35 | going to something more personal. And is that it's time for a |
|
| 81:43 | Okay. Not there's anything great going . But I feel like I've been |
|
| 81:47 | for a bit long. So let's a little break. And right now |
|
| 81:51 | got 1025. So let's take a 10 minute break because that that is |
|
| 81:55 | for everybody. And we'll come back I've got so it's 9:35 for |
|
| 82:01 | So 45, 9 35 9. back at 9 45 9 35. |
|
| 82:09 | minutes were 9 36 and I'll finish . Well, we can't hear |
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| 83:00 | You're on mute. How is that ? Sorry about that. So, |
|
| 83:09 | uh, would continue to talk about strata, graphic concepts Chronos photography for |
|
| 83:18 | means time. So a chronic photographic is a unit of rocks that characteristic |
|
| 83:25 | time interval. And there are geo units, which means geological units based |
|
| 83:33 | the absolute age of something versus quantas and a chronic photographic unit is all |
|
| 83:42 | rocks deposited in a period of chronologically unit is the unit of |
|
| 83:49 | And what's interesting this is stuff that probably should have learned some time ago |
|
| 83:56 | on, you know, people don't teaching formal photography but so you've heard |
|
| 84:01 | the paleozoic era. That's that's the of the time a social with the |
|
| 84:07 | , the air earth um is all rocks associated with the paleozoic era. |
|
| 84:13 | the word for them is a is suffix that we use to designate |
|
| 84:19 | So a cloud of form is a L shaped surface. A clown ofem |
|
| 84:25 | be the sediments deposited between two clans . You'll see here that word common |
|
| 84:31 | use at some point. We have cretaceous period which is the which is |
|
| 84:36 | period of time associated with the cretaceous the cretaceous system is all the rocks |
|
| 84:42 | cretaceous age. Then we have epochs series and ages and stages. And |
|
| 84:48 | it's very common informal photography and you , you guys probably aren't in the |
|
| 84:54 | game but we refer to upper cretaceous and late cretaceous events. Mhm So |
|
| 85:06 | history and geology of the earth are into geological time units. I said |
|
| 85:10 | have we have the chronological periods. there's the arcadian protozoa and fantasize over |
|
| 85:17 | . And those have broken into the Mesozoic and paleozoic eras. The protozoa |
|
| 85:23 | divided into the paleo miso and and protesters OIC eras and then the areas |
|
| 85:31 | are divided into periods and epochs. in addition to the time, you |
|
| 85:36 | also discuss a protozoa like Jonathan um era anthem cretaceous system. There should |
|
| 85:44 | a comma in there. Let's draw in to make sure that you're not |
|
| 85:52 | , whoops better make it red. you can see it there it is |
|
| 86:00 | a stage. So stage age and on and so forth. And of |
|
| 86:06 | here's the same timescale. Now we've the data associated with it. And |
|
| 86:09 | course the timescale is reasonably well dated an integration of chrono metric methods as |
|
| 86:15 | as global correlations and bios photography and Copeland and Don von neumann House also |
|
| 86:22 | an entire course on on Kronos And I'm not sure if that's the |
|
| 86:28 | photography and chronometer corpus. That's all . But Pete will describe the econometric |
|
| 86:33 | to you. All right. And we've got chrono metric units and then |
|
| 86:41 | have chronic strata graphic units. Econometric kind of means the same thing and |
|
| 86:47 | use different Turks, you know? if you actually talk to the United |
|
| 86:50 | Geological Survey strategic for they'll talk about units versus time units. Right? |
|
| 86:56 | Krone strata. Graphic unit is a unit defined on the basis of the |
|
| 87:01 | physical material. The rocks and the was a chrono metric units defined on |
|
| 87:06 | absolute time or the dates as defined from radio metric dating. And so |
|
| 87:14 | example, we look for evidence of late cretaceous extinction event by examining upper |
|
| 87:19 | rocks. So late and upper, as a temporal term, upper is |
|
| 87:24 | physical term. Mhm. So we say that the Hell Creek formation of |
|
| 87:29 | upper cretaceous system contains evidence the extinction ended the late cretaceous period. |
|
| 87:43 | mm hmm. Something else that I to talk about? Um I'm not |
|
| 87:58 | there is a good place to do . But let's just say that your |
|
| 88:16 | Ecologist and you discover a dinosaur and discovery looks like this. I kind |
|
| 89:00 | imagine the bones here ribs. big eye socket, big nose. |
|
| 89:10 | you figured that you're a dinosaur is tons. Okay? And you find |
|
| 89:18 | in the Hell Creek formation. And so you've got a choice, |
|
| 89:26 | a T. Rex or it's a . Godzillas. T rex is |
|
| 89:40 | which means it's got big thick bones the great pillows has thinner bones. |
|
| 89:45 | ? And so you say, you , I'm going to define a new |
|
| 89:49 | of T. Rex. Tedros I think it's a different species than |
|
| 89:54 | robust T. Rex. Okay? you know that if you get too |
|
| 90:00 | you've discovered new t rex, you're get a lot of nature right, |
|
| 90:04 | is the big Kahuna for a publishing a letter to nature. Okay. |
|
| 90:12 | so you submit your paper to And some famous paleontologists review it. |
|
| 90:19 | they say yeah you know we don't you've got a T. Priscilla's. |
|
| 90:24 | think you have a female T. . We think that they were you |
|
| 90:28 | maybe they had thinner bones or maybe mail had thinner bones. But maybe |
|
| 90:32 | know they think it might be a difference between T. Rexes because you're |
|
| 90:36 | a bit of a fight. So paleontologists, we're always trying to |
|
| 90:44 | new species because you get you get get the big kahuna you've defined the |
|
| 90:48 | of new species. But in order you to be allowed to name a |
|
| 90:53 | species, you have to prepare a list which means a list of all |
|
| 91:04 | the fossils that have ever been That might be that that that that |
|
| 91:10 | . Yes you have to have a specimen. Okay. You may not |
|
| 91:22 | this how many of you have been a natural history museum right now there's |
|
| 91:28 | types of natural history museums. The Museum of Natural History, the |
|
| 91:34 | Those are archival museums which means they vast collections in their basement of type |
|
| 91:40 | . Sometimes type specimen is on display the T. Rex at the american |
|
| 91:45 | of Natural History is one of the specimens for T. Rex. But |
|
| 91:51 | museums you know don't aren't archives museums sometimes I was visiting University of |
|
| 91:58 | They published the treatise on paleontology and have an entire building devoted to their |
|
| 92:04 | their invertebrate fossil collection. And they a special room which is for their |
|
| 92:13 | specimens. So a type specimen of bracket part of that trilobite. |
|
| 92:19 | So there are very very strict rules the field of paleontology and biology for |
|
| 92:25 | new species. And the reason is , professional scientists get a lot of |
|
| 92:32 | for identifying something new. But of , you know, it's got to |
|
| 92:37 | peer reviewed and you can't make it , you know, and just because |
|
| 92:41 | Foster looks slightly bigger, that doesn't it's actually new species. Right? |
|
| 92:49 | know. Okay. Great Dean but two different dogs. There's only |
|
| 93:42 | species, but there are different Right? If you found a fossil |
|
| 93:48 | , a fossil breakdown guarantee you every charged unplug would call those different species |
|
| 93:54 | to make the point right? But course we know that there are different |
|
| 93:57 | of one species of dollars. So back to the point I'm trying |
|
| 94:17 | make here. So when a so we have the same problem with |
|
| 94:24 | , right? If you work for USgs United States Geological Survey and I |
|
| 94:29 | for the State Survey of texas. a lot of glory in defining a |
|
| 94:32 | formation, right? And if you if you let the photographers one |
|
| 94:37 | they keep to find new formations in to prevent proliferation of names. Most |
|
| 94:45 | have a strata graphic policemen that might a member of the North American Commission |
|
| 94:49 | strata. Graphic nomenclature. So most the major geology journals will have a |
|
| 94:54 | graphic expert that that that if if geologist defines a new formation, it |
|
| 95:01 | to go through that person's opinion, peer review. If you want to |
|
| 95:06 | up a new formation, you with a fossil, you can take |
|
| 95:09 | fossil and put it in a can't do that with the formation. |
|
| 95:14 | ? So what you do in in photography as you set up a tight |
|
| 95:20 | . Okay. It's not being locality the type section occurs. Okay. |
|
| 95:28 | the formation is commonly named after a . So the pharaoh and sandstone is |
|
| 95:33 | after the town of Faron where where outcrop is exposed. The Dunvegan formation |
|
| 95:39 | did my PhD on is named after Dunvegan Bridge that goes across the Peace |
|
| 95:44 | and the Dunvegan exposed on the banks the Peace River. So the same |
|
| 95:50 | that you have to, you have have a type specimen that will be |
|
| 95:54 | away in a drawer in an archival geologists have to set up type sections |
|
| 95:59 | say this is the this is the section where this formation was defined. |
|
| 96:05 | . And you should always correlate away the type section. In addition, |
|
| 96:10 | days will well if you're trying to up a global correlation for these krone |
|
| 96:20 | graphic units. There will be a section that defines the this is oak |
|
| 96:26 | . The touch section for the Jurassic boundary that's sometimes referred to as golden |
|
| 96:32 | . And these global strata, type are all over the world. |
|
| 96:36 | And uh they they help to enable . The point being is, there's |
|
| 96:42 | of rules and regulations around naming new and setting up type sections and all |
|
| 96:47 | stuff. Type section is going to problematic because, you know, some |
|
| 96:52 | sections for example, in the US might have been defined in the 50s |
|
| 96:56 | now in private land and don't get to them anymore. Well, maybe |
|
| 96:59 | was a highway built and it destroyed type section. Right? So type |
|
| 97:03 | aren't always stable, you know? have you ever heard of the spine |
|
| 97:10 | ? It's the it's a cretaceous It's a meat eater and it's got |
|
| 97:20 | spines on the back. Okay. was in Jurassic, one of the |
|
| 97:23 | world movies Anyway, the type specimen in that was in a museum in |
|
| 97:29 | owned by the Germans in the Second War. There's photographs of the type |
|
| 97:34 | that the museum was bombed and the were destroyed. So even type specimens |
|
| 97:40 | be destroyed if you get into a zone. Mm hmm. Now back |
|
| 97:47 | the day, we were struggling with to define terms strata. Graphic units |
|
| 97:52 | on bounding surfaces and quaternary photographers, people working on mapping sand or gravel |
|
| 98:02 | would typically described three major strata graphic , terrorist deposits, queue for quaternary |
|
| 98:09 | for terrorists, which basically meant Sultan Alu V um and then gravelly Lucia |
|
| 98:15 | LG. Okay. And of course Matthew, you know, if you've |
|
| 98:20 | a river valley and you've got a of gravel here and some sound there |
|
| 98:27 | then some terrorist deposits. So in view, because paternity sediments are never |
|
| 98:32 | , there's still sediments, You you would only ever map one unit |
|
| 98:36 | plan view but that began the rails cross sections that was into fingering of |
|
| 98:42 | little faces. They weren't actually cronista humans. They said, well, |
|
| 98:46 | know, the gravels can correlate to stones or terrorist deposits and the typically |
|
| 98:52 | by paleo souls and erosion of surface form as a result of the glacial |
|
| 98:58 | . He said, let's let's define strata. Graphic units that break up |
|
| 99:03 | these these little strata. Graphic units surfaces bound into strata. Graphic units |
|
| 99:09 | by key surfaces and these elite Graphic units. Unit one Includes Sand |
|
| 99:18 | Clay. You know, two includes and clay. You know, three |
|
| 99:25 | conglomerate, clay and sand and so and so forth. And the soil's |
|
| 99:31 | the disc, the disc conformity. used to subdivide the elite strata. |
|
| 99:35 | fuels but these essentially are the same as sequence boundaries. Okay, so |
|
| 99:47 | the Alice strata graphic and somehow the photographic community managed to get this into |
|
| 99:52 | strata graphic code. They had Alice formations, our groups, our |
|
| 99:58 | Now you will clearly recognize that there's a surface of continuity That separates one |
|
| 100:05 | 2. But there's no discontinuity So Alice photography did not define a |
|
| 100:10 | conformity. So it was much more to the content of sequences. Is |
|
| 100:16 | kind of the 50s and 60s. I was in the business of defining |
|
| 100:24 | bounded strata graphic units in the early the early nineties before sequence to trigger |
|
| 100:33 | he was in the strata. Graphic still isn't. And so I did |
|
| 100:37 | a lot of work on Alice Graphic definitions, thinking it might actually |
|
| 100:44 | off in the community. Looks at rocks. Never did. It is |
|
| 100:50 | only formally recognized this continent abounded nomenclature available for formal naming of units bounded |
|
| 100:57 | discontinuities in the North American commission of . Graphic nomenclature. Now the earth |
|
| 101:04 | a big magnet and the magnetic pole switched back and forth many times |
|
| 101:10 | such as in the neo gene. flipped back and forth. Oh goodness |
|
| 101:15 | I should be able to count I do this every year. I |
|
| 101:18 | never remember how many stripes are black normal polarities. That's that's the magnetic |
|
| 101:23 | points north. What is reverse Which means your accomplice points south and |
|
| 101:28 | flipped. Uh there has been 123456789 13 14 15 16 17 18 1920 |
|
| 101:39 | 15 16 2020 30 30. About . So 60 changes Over the past |
|
| 101:47 | million years. Right? Sorry, million years. So what I say |
|
| 101:54 | 60 changes divided by 15 million 60 x 15 is I should know |
|
| 102:15 | four, Is that right? That means there's about about four reversals |
|
| 102:22 | million years. That means there's one about every 250,000 years. Okay, |
|
| 102:31 | magnetic photography in the my scene is for subdividing rocks down to the race |
|
| 102:37 | about 250,000 years. That's better than . Okay. And of course we |
|
| 102:48 | we can actually measured the ages of minerals in the sea floor because it's |
|
| 102:57 | rock and get the absolute ages of of the oceans. Just as a |
|
| 103:02 | side. You know, I spent lot of my time in the |
|
| 103:05 | Main Ian. And interestingly from about two, million years ago, it |
|
| 103:11 | a long period called the cretaceous long when there was no change in the |
|
| 103:16 | field. No one's really sure why was such a long period of time |
|
| 103:20 | no change. It does mean that that magnetic photography isn't useful for subdividing |
|
| 103:28 | beloved mid cretaceous rocks. It's very for santa's OIC correlations. Okay, |
|
| 103:38 | magnetic photography defines a polarity crawl. Cron is short for Chronos photographic. |
|
| 103:48 | we have normal and reversed Cron's. those are the magneto strata graphic units |
|
| 103:54 | they are expressed in absolute agents. can also define units in the base |
|
| 103:58 | police calls or penance photography. That of links back links back to Alice |
|
| 104:04 | , which is largely based on the of soils in quaternary sediments. |
|
| 104:13 | so that's basically just gives you a bit of a background informal strata graphic |
|
| 104:20 | and there's a couple of takeaways. is there are very strict rules for |
|
| 104:25 | new things and that there are, know, if you will scientific police |
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| 104:30 | are designed to prevent the proliferation of to try to get the normal |
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| 104:35 | not be too out of control. said that here we are worrying about |
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| 104:43 | photography, which of course reflects a of things. What is the increasing |
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| 104:50 | of subsurface data? Cross sectional views try to decipher sand, shale couplets |
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| 104:57 | reservoir seal pairs in the oil fields opposed to general mapping using a compass |
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| 105:06 | walking around like Mcdonald's and Angela did their field camps, there's also recognition |
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| 105:12 | there is a high frequency alternation of and non reservoir units. A lot |
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| 105:18 | that is linked to these ideas of cycles and those Milenkovic cycles are kind |
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| 105:23 | into tens of thousands of years much, much faster than polarity chrome's |
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| 105:30 | bio zones. And if you want get the reservoir flowing units mapped in |
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| 105:37 | oil fields, we need to get as a much finer scale of |
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| 105:42 | And of course there's also this explosion walther's law facing said um Atala ji |
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| 105:47 | strata graphic units at much higher resolution the kind of photography practiced in the |
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| 105:53 | , forties, fifties and sixties that describe in our next lecture coming |
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| 105:59 | So what are some of these informal ? We're going to focus in this |
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| 106:04 | on seismic and sequence photography. And not going to read out all these |
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| 106:10 | , but we'll review them in detail later lectures. Mhm There was a |
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| 106:16 | interest back in when I was a student and and it partly related back |
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| 106:22 | this explosion of the understanding of physical that deposit sediments that people recognized |
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| 106:30 | You said it yesterday very well when were talking about what's the deposition environment |
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| 106:36 | our deep water lake. And you the first student to use the word |
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| 106:41 | nights and the turbine night is the of activity current. That's an |
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| 106:46 | Right? So the, the, , the And turbine lights weren't really |
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| 106:52 | until the late 50s, early the identification of turbulent beds, which |
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| 106:58 | a single event, a storm which I talked about briefly yesterday when |
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| 107:03 | talk about walter's law and I talked storm events. Roger walker was one |
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| 107:07 | the early proponent or discoveries of hamachi stratification, which is a physical physical |
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| 107:13 | structure produced by an individual storm. the identification of, of storm |
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| 107:20 | uh termine ites and bentonite, which altered ash flows allowed us to identify |
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| 107:26 | individual events and strategic graffiti getting very for correlation and and and in a |
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| 107:31 | an extinction event could also be some of an event horizon. And then |
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| 107:36 | course, as people start to get this idea of climate cycles driven by |
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| 107:42 | in the Earth's orbit. There's been is and continues to be a large |
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| 107:47 | of researchers attempting to subdivide much of strata graphic record on the basis of |
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| 107:55 | of these high frequency climate cycles at of 20,000 years or or or |
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| 108:09 | Okay. And that's that's that's That's actually becoming known as a new |
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| 108:16 | called Astro chronology. G. There go. Astro chronology is a subdivision |
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| 108:32 | the rock record on the basis of lack of its cycles tied to chrono |
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| 108:38 | data. Right, so one of interesting developments is with the development of |
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| 108:44 | no bless laser ablation mass specs such brad singer at the University of Wisconsin |
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| 108:51 | they're getting aged dates with a precision plus or -10 2%. So if |
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| 109:00 | have 100 million year old rock, , .02% of 100 million years Is |
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| 109:09 | years. Okay, so that allows to get absolute age dates for absolute |
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| 109:15 | that can be correlated directly to a model accurate cycle. Exxon thought that |
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| 109:22 | were going to develop a new a uh a new chrono strata, graphic |
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| 109:30 | of the entire history of the I something even better than this, |
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| 109:38 | even more detailed than this using sea curves. Which products which give a |
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| 109:43 | higher resolution subdivision of time than these of stages at ages. All of |
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| 109:50 | are based on bar. And so kind of set the stage for um |
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| 109:58 | astro chronology. But with this new dating technique that pipe dream is now |
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| 110:04 | a reality. Okay. And there some other informal schemes that have come |
|
| 110:10 | gone. I kind of like these . I. S. Was genetic |
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| 110:15 | of strata by Daniel Bush in the because if I say gs now you |
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| 110:20 | of geographic information systems. So that caught on formats. You know |
|
| 110:26 | we talk about formatting uh code James at the University of Oklahoma, interesting |
|
| 110:33 | . His scheme was forgotten but but these scientists that have a lot of |
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| 110:38 | work these guys did was based on logging correlation, something that I'm a |
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| 110:42 | fan of for better for worse. schemes never quite caught on but they |
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| 110:47 | on the right track. So now got to end with two two |
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| 111:03 | you know, what's the purpose of , right? You know if you |
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| 111:08 | go into the field and say oh A B C D E F |
|
| 111:11 | One of the letters, you sometimes it's easier to say, oh |
|
| 111:14 | Austin chalk, you know, the Farron sandstone, you know, |
|
| 111:24 | name is unique. And so it a lot of confusion of letters and |
|
| 111:30 | . And of course there is some to the scientist. That's the first |
|
| 111:35 | . That name something you want the to be coherent. Sometimes a name |
|
| 111:41 | the fair, it is easier to than, you know, formation AX- |
|
| 111:46 | . You feel like, you you know, I remember one that |
|
| 111:50 | could get personalized license plates. You who the hell remembers their license plate |
|
| 111:54 | , right? You know, when say, oh you can have your |
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| 111:58 | plate and I'm like, yeah, McVie, john McVie, you |
|
| 112:00 | no one's gonna, my, I a pretty unusual first name. It's |
|
| 112:04 | east indian name is Madonna probably knows , you know, and my twin |
|
| 112:09 | name is who is a famous realized king, Jonah was a mythological king |
|
| 112:15 | there's far fewer jobs than there are . So I always figured if they |
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| 112:19 | had a personal license plate, I use my first name. Right? |
|
| 112:24 | , you know the reason why we names not numbers is it's easy to |
|
| 112:28 | , right? It's easy to Angela than if you had a |
|
| 112:32 | you know, person, XY 23 . You know, or or you |
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| 112:37 | think about passwords right. You know the user generate that generate automatically generated |
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| 112:43 | are incompetent, incomprehensibly difficult to However if you have too many names |
|
| 112:49 | formations you know you can get The other purpose of photography is to |
|
| 112:57 | things. What we want to what do you call that we're |
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| 113:01 | Rocks with rocks were trying to correlate or some combination. What's the business |
|
| 113:10 | ? Okay if you're trying to explore a reservoir, we want to know |
|
| 113:15 | its architecture is, How big is , how continuous it is It is |
|
| 113:19 | it have is it broken up into compartments? How many well do you |
|
| 113:23 | wells? Do you need to get heart of carbons out of it? |
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| 113:26 | your water flooding, where's the water to go? Will it leave bypass |
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| 113:30 | behind? What's the percentage of oil you'll get out of your field? |
|
| 113:34 | are all the big questions we ask the petroleum business every day. We |
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| 113:38 | to understand all the strata, graphic of the petroleum system and that means |
|
| 113:43 | the source the seal the trap And course the reservoir is the Big |
|
| 113:48 | Right and how how continuous the reservoirs of course strategic graffiti is a tool |
|
| 113:57 | making good maps, bad photography, maps, good strategic strategic graffiti, |
|
| 114:04 | maps. Some years ago my former player Jazz Duke, sorry um Doug |
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| 114:16 | who is a senior geologists Chesapeake asked to. He said we need someone |
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| 114:21 | teach our students mapping or our employees . He said, no, you |
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| 114:25 | , mapping is easy. Photography is . Let me teach your students how |
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| 114:30 | do better photography and the map. will be easier. He said, |
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| 114:33 | , you're probably right. And so gave him a course on advanced |
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| 114:37 | which the course were taken from me the next few weeks. So there |
|
| 114:44 | lots of arguments about photography if different strata graphic units are the same by |
|
| 114:51 | graphic age. She has been called same, you know, different different |
|
| 114:56 | . And so there's always been a between bonds photographers and little photographers who |
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| 115:01 | on the biological content, which is thing or they're the same age. |
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| 115:05 | , but that's a sandstone. That's share that should be in different |
|
| 115:08 | but at the same age. But there are different mythologies. And |
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| 115:12 | there's been a lot of discussion about versus nomenclature and I'm gonna talk about |
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| 115:17 | in the next lecture. And tell the problem that should be got into |
|
| 115:22 | the 60s and 70s. The correlation linkage of faces. Ah and the |
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| 115:29 | strata. Graphic rate relationships. that's fundamentally what sequence photography addresses. |
|
| 115:41 | , that's it for our second Any questions or discussion about that? |
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| 115:55 | as clear as shale. Right, , now. Mm hmm, I |
|
| 116:04 | another lecture to go, which will of take, I'm not sure What |
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| 116:13 | is it there now. 10 after , isn't there? Um Thanks the |
|
| 116:20 | lecture. I can start it or could take a break and then just |
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| 116:24 | it. What would you prefer? started and then take a break midway |
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| 116:31 | . Yes. Okay. Wanna make we get plenty of breaks because you |
|
| 116:36 | , we're lecture heavy on this first as we move forward. We'll we'll |
|
| 116:41 | more exercises. Okay. But we've to get through some stuff and I |
|
| 116:47 | of feel like mornings, students are bit more alert, so Okay. |
|
| 116:57 | . What I'm going to go through is a little history of ideas of |
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| 117:02 | photography. Base level control of I'm ready to add class 1949 63 |
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| 117:46 | then wheeler again fifties to the So I'll go through the contributions of |
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| 118:03 | scientists and how it develops sequence The Amadeus group about was an american |
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| 118:14 | . He was at M. T. And uh ended up in |
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| 118:18 | where he where he died. and was an early authority on the |
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| 118:24 | of china. And he developed the of sedimentary overlap. We're going to |
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| 118:32 | about lap out a lot in this . So here's an example of one |
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| 118:37 | his diagrams from his 1906 papers. this shows a cross section that actually |
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| 118:47 | right through texas or the Oklahoma. taught at ut Dallas for many |
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| 118:56 | And I would routinely take students up the Arbuckle Mountains. Look at the |
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| 119:00 | limestone. Uh and that's uh there's Simpson uh sandstone or the Simpson group |
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| 119:07 | stones and separated by the ST peter . The sedimentary rocks overlying the pre |
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| 119:14 | brick old land. Love that term came brick or you can be an |
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| 119:20 | land. And on the upper we have two strata graphic cross section |
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| 119:25 | the lower diagram. He's just not schematic a depiction of the layers without |
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| 119:30 | the theses details. So he's got one two and three. Okay. |
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| 119:40 | those are overlapping the pre catholic old . Okay. And we refer to |
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| 119:47 | termination of a younger surface or layer it on an older layer as |
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| 119:56 | that's the current term we use for . Okay. And then units |
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| 120:04 | five and six terminate against an upper . Okay, So we've got on |
|
| 120:15 | units. Okay, Whoops. We've online units. And then we got |
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| 120:37 | communities. So that relationship there where older surfaces terminally against a younger |
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| 120:48 | we call it top lines. And we have another unit 9, 10 |
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| 120:55 | 11. And what are those doing lap in? Thank you. So |
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| 121:05 | we've got so we have on lapping flapping or top clapping and on lasting |
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| 121:11 | . So those are terms we use sequence surgery today. Those terms were |
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| 121:15 | by Grubauer in 1906 in describing the lap out relationships or overlap relationships of |
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| 121:24 | photography in North America. Mhm. a more detailed diagram again from your |
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| 121:32 | paper. So Back in 1906 we publish the color. He's got unit |
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| 121:42 | B C and D. Each of units consists of limestone passing into |
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| 121:49 | passing into silt and then sandstone. , so this is shoreline sandstone going |
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| 121:55 | limestone and then m stands for the of marine erosion. That's basically the |
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| 122:02 | face, the area where marine processes disallowing mud to settle. Okay, |
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| 122:08 | got a nice clean uniform draw. the uniforms are straight. Okay, |
|
| 122:15 | not sure any curvature there. I might sort of draw these with |
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| 122:19 | bit of curvature, but that's And I just went went ahead and |
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| 122:23 | the faces. And so this is long. Right? The reason that |
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| 122:27 | could put sandstone on top of shell top of limestone is because they lie |
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| 122:31 | to each other at any given point time. So there's what Walther's law |
|
| 122:35 | 1880 something. And Grandpa was well Walther's law. Once again, he's |
|
| 122:41 | these top lasting relationships. Right? , quite a sophisticated looking diagram For |
|
| 122:51 | , Of course there's a diagram from textbook John Van Wagoner in 1990. |
|
| 122:56 | , the differences. Van Wagner shows , lap which an upper surface termine |
|
| 123:01 | the lower surface, but it doesn't the top lap that Grabau shows but |
|
| 123:07 | , very similar looking diagram. Here's diagram from gravel. Same paper. |
|
| 123:16 | . And so here is his cross , right? You know, it's |
|
| 123:19 | B c D E f G H I. And now he shows them |
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| 123:23 | the right into thomas photographic diagram. now on the vertical axis, we've |
|
| 123:28 | time on the left, we have . Okay, I am going to |
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| 123:37 | asking you to convert a physical cross section into a time strata graphic cross |
|
| 123:44 | . That's a skill you're gonna learn this course. Right? So look |
|
| 123:48 | these cross sections carefully. Now, interesting is, here's a single little |
|
| 123:53 | graphic unit, right? That would equivalent to the ST peter sandstone. |
|
| 123:58 | the single Lysistrata graphic unit in the photography has a whopping uh, time |
|
| 124:04 | in the middle of the big on . The highest decreases as you go |
|
| 124:09 | land. So this would be the part of the cross section. That |
|
| 124:15 | be based on the distal and the decreases in size until eventually the units |
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| 124:20 | confirmable. That would be what we the correlative conformity. Mm hmm. |
|
| 124:26 | again, you notice that each of units hetero lipstick, you've got lime |
|
| 124:30 | , shales and sand stones in a strata graphic unit. So, these |
|
| 124:34 | timelines, right? And so the that are dipping in physical space become |
|
| 124:40 | in time space because they represent a point in time. Does that make |
|
| 124:48 | ? Okay, Elliott Blackwelder was at University just a few years later than |
|
| 124:56 | than and again, here's the gulf geology and we see evidence of of |
|
| 125:05 | this is this is one of these strata, graphic diagrams and we see |
|
| 125:09 | . So the lower the lower units be all flapping seaward and then they |
|
| 125:16 | be transgressive and wheeler space. The units look like this and your flapping |
|
| 125:24 | . Ah look like this again with hiatus. Okay, so there's the |
|
| 125:34 | photography that leads to the time photography you see depicted here. And then |
|
| 125:41 | would look at some sort of geological section. We've got some metamorphosed |
|
| 125:47 | You gotta fold and thrust belt. big future with some lime stones, |
|
| 125:52 | blanketing quaternary gravels. Uh And here got paternity gravels over metamorphic rocks. |
|
| 125:58 | you have a much, much longer of time missing. And then here |
|
| 126:03 | got less amount of time missing. he's looking at this discordance between units |
|
| 126:07 | there's none slight prominence and maximum. , now in in black. |
|
| 126:13 | this time he had no idea what absolute time of the earth was. |
|
| 126:18 | we could only guess as to the of the various formations. Okay, |
|
| 126:26 | interesting is Blackwelder made a cross section the entire continent. So you noticed |
|
| 126:32 | , you know, in texas, know, and you may or may |
|
| 126:37 | know about this, but you if you go to, if you |
|
| 126:40 | just north of Dallas, you'll see exposures of the ordination in Mississippi and |
|
| 126:47 | stones of the Arbuckle group. If go to just west of Fort |
|
| 126:53 | this beautiful exposes the pennsylvania, permian . And then of course, if |
|
| 127:01 | , you know, if you go the Austin area, you'll see nice |
|
| 127:05 | of the cretaceous tertiary successions. It's very poor record of Jurassic and Triassic |
|
| 127:10 | up in onshore texas. But if go offshore you get the luann salt |
|
| 127:16 | there's a good record of Jurassic Triassic , but there it's all confined to |
|
| 127:20 | offshore of course in Blackwells today, oil, those formations hadn't been |
|
| 127:25 | So he didn't know, he didn't they were there, although they are |
|
| 127:29 | in texas, but they're they're they're they're buried below the cretaceous successions and |
|
| 127:35 | only found by drilling because, you , I grew up in Newfoundland and |
|
| 127:40 | and of course, you know, a good paternity and of course I'm |
|
| 127:44 | the great lakes right now and I'm area that's covered by paternity gravels left |
|
| 127:49 | the retreat of the last ice So this shows that the history of |
|
| 127:53 | photography across the entire continent of north . And of course these white spaces |
|
| 128:01 | represent the big on conformity is And and these would represent the major |
|
| 128:06 | . Graphic sequences in north America identified 1909 based largely on our crop data |
|
| 128:14 | almost no subsurface data in black. , this time joseph Farrell died quite |
|
| 128:21 | sadly. He was a professor of geology at Yale University And in his |
|
| 128:27 | paper on criteria for identifying Deltas. produced this diagram which I love |
|
| 128:35 | I've colored it up. So this this is his original diagram. I |
|
| 128:37 | added colors to it. He's you know, A. B and |
|
| 128:42 | . The delta is divided into top four set on the bottom set. |
|
| 128:48 | your client form, right? And propagating the contact form. So in |
|
| 128:53 | day, the platform is kind of this in unit B. The platform |
|
| 129:00 | building vertically and the uniform. See a big step back. Okay, |
|
| 129:07 | all of a sudden a barrel has done what you did in the very |
|
| 129:11 | exercise yesterday at the beginning of the and what you worked on last night |
|
| 129:17 | which reviewed this morning. So there's nice example of barrels attempt at my |
|
| 129:23 | or I should say my attempt to you the exercise that barrel figured out |
|
| 129:28 | years ago just to make sure that understand there's nothing new under the |
|
| 129:34 | Right? What's interesting is during stage He says that's the strata, graphic |
|
| 129:40 | that's produced when you have no set to change. So I summon supply |
|
| 129:45 | system basically just pro grade then in be the sea level rise matches the |
|
| 129:53 | rate. So the the the magnitude sediment coming in is matched by the |
|
| 129:59 | of rise. Therefore Sistema grades grades . Okay. And then in step |
|
| 130:05 | sea level rise is greater than the . He didn't use these terms. |
|
| 130:12 | just added those terms to make it to make it back to the sequence |
|
| 130:19 | . And so we see an extremely looking correlation to this day. I'm |
|
| 130:24 | quite sure how or where he understood these geometries. What's also interesting if |
|
| 130:32 | look very carefully, He's got two . Okay. He's got a small |
|
| 130:38 | which is the little delta front. money's got his shelf slope break. |
|
| 130:44 | . And all I did was put little wedge underneath that we left that |
|
| 130:50 | grade but eventually they will coincide. . And maybe you get some deep |
|
| 130:59 | deposits in here. And Burroughs Tommy have known much about deepwater submarine fan |
|
| 131:04 | because there was no oceanographic identification of things. This is really quite a |
|
| 131:11 | cross action. It's 100 years And so here is another another diagram |
|
| 131:21 | joseph Borrell and this was showing the of of a land and Seascape as |
|
| 131:26 | result of sediment supply and tectonics. tectonics is a very old concept in |
|
| 131:34 | time tectonics referred to the vertical lifting degradation of the landscape. He didn't |
|
| 131:39 | plate tectonics, we did understand that build up and then they get eroded |
|
| 131:45 | . So again here we've got the colon form, there's your delta front |
|
| 131:49 | shore face and there's your shelf slope and these platforms are building seaward. |
|
| 132:00 | green represents your pyre alec or numbering building behind the delta as the mountains |
|
| 132:06 | . So you get to maturity or aggression and then the mountains erode away |
|
| 132:13 | shrine transgressors and lo and behold, what happens. Do you see that |
|
| 132:17 | green is removed? The green, green toxic faces are removed by the |
|
| 132:24 | . There is the shore face It is right. A little show |
|
| 132:29 | face. Remember I talked about the face, right? The area were |
|
| 132:38 | are able to erode the substrate so surface there as a transgressive surface of |
|
| 132:44 | that's eroding away all of the green . So barrel model did Burrell coined |
|
| 132:50 | term shore phase. He also demonstrated it can cause extreme levels of |
|
| 132:56 | They demonstrated 100 years ago, pretty stuff. Now, back in the |
|
| 133:06 | , we didn't know the absolute age the earth. Clair patterson, who |
|
| 133:13 | very concerned about lead contamination. Built first extreme clean labs In the late |
|
| 133:20 | the mid 1950s, 1955 Clair patterson his first clean labs to date the |
|
| 133:39 | ratio of uranium and lead daughter products meteorites demonstrated the meteorites. We're about |
|
| 133:51 | 56 billion years old, thereby pinpointing time at which the solar system and |
|
| 133:59 | reforms Prior to 1955, we were at the age of the earth and |
|
| 134:05 | age of rocks, What's Paterson? might be patterson er Yes er |
|
| 134:14 | So Clair Patterson developed Giffords, the really robust radio metric dating and once |
|
| 134:21 | did it with, with, with , people started to date earth rocks |
|
| 134:26 | began to start getting the accurate ages the strata graphic column. But before |
|
| 134:35 | sentiment ologists said, wait a minute got the stack of rocks and we |
|
| 134:39 | roughly how long it takes to you know, a centimeter of |
|
| 134:44 | So if you have 10 m of in the deposit seven millimeter per year |
|
| 134:49 | we know that we have, you , 10 m of play mm per |
|
| 134:53 | . That would be ah 1000 millimeters meter. So let me 10,000 |
|
| 135:00 | Okay, deposit a meter of Okay. He said he had the |
|
| 135:05 | is the strata graphic called this filled breaks. So he started to try |
|
| 135:10 | use these time strata, graphic diagrams figure out in a vertical column of |
|
| 135:15 | based on a variety of base level . So A is the primarily curve |
|
| 135:20 | rising base level that equals a Okay, that's a subsidence curve and |
|
| 135:31 | increases and then and then it increases , very slightly varying subsidence. Then |
|
| 135:37 | got B which is the diocese diocese oscillations giving dis conformity ease. |
|
| 135:43 | so those are basically the big on ease, Probably tectonic in nature. |
|
| 135:53 | then the mater oscillations are the melancholic . Climatic wounds. So that's the |
|
| 135:59 | stuff. What he recognized is that this is time on the, on |
|
| 136:04 | on the horizontal axis and thickness on vertical axis. What Burrell realizes that |
|
| 136:11 | a tiny fraction of the vertical column rocks actually represents time. Most of |
|
| 136:18 | time is actually captured in the surfaces layers. So we realized you can't |
|
| 136:23 | simply add the thickness divided by the multiplied by the sedimentation rate and get |
|
| 136:28 | duration of the rock column. You've to put all these on conformity is |
|
| 136:33 | ? And they were trying to figure how much time is represented by thick |
|
| 136:36 | like you see in the Grand Ultimately they weren't able to really get |
|
| 136:41 | . And ultimately we needed we needed metric dates and buyers strapped to really |
|
| 136:45 | at the absolute agents. Now here's a diagram from the textbook and |
|
| 136:52 | we bought the subsidence curve, linear and that's who proposed on three base |
|
| 136:59 | changes A sorry, a slow one third on the use static cycle for |
|
| 137:06 | . You static cycles and fifth order produce a composite. Use static curve |
|
| 137:11 | then is integrated with the substance curve ultimately allows you decide where, you |
|
| 137:18 | . So here in this area we've not much subsidence and big seat of |
|
| 137:21 | falls. You get lots of incised and in conformity ease as you go |
|
| 137:26 | the party basis part of the basin experiencing more subsidence. You get upper |
|
| 137:32 | para seekers from flooding surfaces and you get the big erosion. One size |
|
| 137:36 | . So we see see valley cutting we've got low subsidence and we see |
|
| 137:41 | preservation of the paris sequences where we less subsidence. I do find these |
|
| 137:47 | to be rather similar, don't accuse of anything, but it's interesting that |
|
| 137:57 | next time put together this diagram with reference to Morel. So, you |
|
| 138:01 | , you wonder who had what inspiration the next person talked about Larry Sloss |
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| 138:09 | he applied Black Wilder's and wheeler's ideas sort of refined Black welder's mapping of |
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| 138:16 | across north America. The big difference sloths and Blackwelder, This loss had |
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| 138:22 | more information and data by the 60's 1909, when Blackwelder published his first |
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| 138:30 | to 1963, when Slots published his , there was a wealth of subsurface |
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| 138:39 | . Uh huh. One of the that happened and it's something that I |
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| 138:43 | of went back and filled in after became a professional when I was in |
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| 138:49 | . As a young geology student, went to my first lectures and people |
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| 138:54 | about the devonian carboniferous rocks, the or division succession. So it seemed |
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| 139:00 | that the relatively continuous ST strata, successions of North America, the boundaries |
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| 139:08 | correlate with the with the european period . They occurred in between. Thank |
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| 139:14 | . And slots recognized that there were big on conformity ease marked by these |
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| 139:20 | areas. The un conforming became more in the middle of the continent with |
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| 139:26 | preservation. So middle of the continent and the margins both west and east |
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| 139:35 | . There it is. The Appalachians the cordillera had much more continuously preserved |
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| 139:40 | of rocks of all these ages. as a sort of true aficionado. |
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| 139:53 | who I think he's trying to our nations and get away from a european |
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| 139:59 | terminology. Use the names of first to designate the sequences. So we |
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| 140:06 | the sox sequences which is the Campbell division than the typical new, which |
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| 140:10 | or deficient to devonian. This is absa roca which is pennsylvania, Triassic |
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| 140:18 | , the zuni and of course the , which is the last, the |
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| 140:27 | cenizo big transgressive regressive sequence. So was the first to define continent wide |
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| 140:34 | conformity bounded sequences. And he used word sequence to designate a regional un |
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| 140:40 | bound body of rocks separated by un Elise Peter van was a graduate student |
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| 140:46 | Northwestern University where Larry sloss tall Now you start to see how Larry |
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| 140:53 | basically influenced scientists who ended up in energy and then later excellent cooperation and |
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| 141:02 | applied the learnings from northwestern to the of seismic data that's got us the |
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| 141:09 | photography, which will be the next gift. Here's an example of losses |
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| 141:17 | sections. So here we've got the socks sequence. Uh, you've got |
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| 141:27 | angular on conformity ease separately the folded sequence from the overlying typical new. |
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| 141:36 | this is kind of in the Williston and Montana going into Canada all the |
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| 141:42 | to Nevada. And then here's a section going from Wisconsin into Appalachians. |
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| 141:48 | we see the same formations. The limestone is equivalent to the the Lockport |
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| 141:56 | that forms the cliff over which Niagara Falls Falls, which represents the sox |
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| 142:03 | right here in the Hamilton area. there's a ST peter sandstone uh that |
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| 142:09 | saw way back in grandpa's time that the sock from the tippy canoe. |
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| 142:16 | , these sequences were identified in the mapped across the north american continent by |
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| 142:24 | Wilder. And then the mapping was by sloss, who formally named these |
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| 142:31 | , trying to sort of introduce a north american centric terminology as opposed to |
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| 142:35 | using the european stations. And here's example of of the younger zuni sequence |
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| 142:45 | uh, the uh zuni, which be under overlying me Erica. And |
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| 142:55 | and he got the Panasonic rocks here who you've got there is the macro |
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| 143:00 | . That's my beloved cretaceous rocks. those are there's the little arc that's |
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| 143:04 | Triassic Jurassic salts in the gulf coast land by the Comanche in gulf, |
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| 143:11 | is again that the the the cretaceous over sequences in the gulf coast |
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| 143:20 | And so if we compare sloths and , when we see the diagrams look |
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| 143:23 | similar now, Larry slaughter, in addition to his profound work on |
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| 143:34 | mapping physical sequences, was also assessing theory of how sequences form as a |
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| 143:40 | of changes in in accommodation and settlement . And we talked through this diagram |
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| 143:46 | extensively in our last yesterday, so won't review that again. Just remind |
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| 143:53 | that he also made major contributions Okay, we're just gonna take a |
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| 144:06 | break here. We're not gonna take formal break. Mhm. Just a |
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| 144:14 | stretch. Yeah. This next section . This next section is a bit |
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| 144:22 | a slog. Okay. It's going get very complicated and very confusing. |
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| 144:28 | hmm. So we'll just take a break. MS for a minute or |
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| 144:50 | and I'll just maybe wait for and to get back and I'll start back |
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| 144:54 | . Mm hmm. Yes, mm . Mhm. Oh, as soon |
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| 155:00 | so eul meu sir, did you anything I said before in this |
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| 155:10 | No. Okay, better start Okay, so Harry, want to |
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| 155:16 | the concept of times photography which we as as having time versus thickness on |
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| 155:22 | vertical axis. We do recognize that are important as the rocks. |
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| 155:29 | And we are depicted exploded strata. cross sections with tom and the vertical |
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| 155:34 | . And he developed a complex nomenclature describe these un conformity ease including the |
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| 155:44 | , which is the time of non . That includes the hiatus, which |
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| 155:50 | the time which there was no depositions well as the vacuity which is the |
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| 155:55 | where there were rocks or sediments that been eroded away. And I'll review |
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| 155:59 | with examples later. We are probably of the, so that's the sort |
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| 156:07 | fundamental papers on the theory of sequence . For reasons I didn't understand at |
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| 156:12 | time. It is he never really on, you know, I think |
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| 156:15 | was an important figure for some reason work wasn't that well quoted and people |
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| 156:21 | of seemed to kind of bypass his two sequence photography. And when I |
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| 156:26 | teaching sequence photography, I was interested understand why Wheeler had not been particularly |
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| 156:32 | and why his ideas hadn't caught on that well. So I went back |
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| 156:37 | some of his earlier papers published with Mallory who was a paleontologist that he |
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| 156:43 | with and they wrote a series of and the the the purpose of these |
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| 156:50 | was to explain how how formal literacy was being practiced In the 40s and |
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| 156:58 | . So in some ways these were of reviewed papers, they weren't suggesting |
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| 157:03 | ways of doing things. They were of explaining that this is really the |
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| 157:07 | that these formations are being named. these are the concepts used to define |
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| 157:13 | in the 40s and 50s in particular a lot of those, a lot |
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| 157:19 | those techniques involved the use of arbitrary to define formations. So we've got |
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| 157:30 | couple of examples here to sort of the thinking. So we've got two |
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| 157:40 | . Okay, and formation B is sandstone formation, is a shale and |
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| 157:45 | they enter finger in between. the question is how do you subdivide |
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| 157:53 | region where they enter finger? So have said we and mary said, |
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| 157:58 | you've got a couple of choices, can decide uh like sand stones |
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| 158:06 | So I'm going to define this tongue a member of B. This tongue |
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| 158:13 | a member of B That 5th time a member of B. That several |
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| 158:18 | as a member of B. But what do you do with the shelves |
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| 158:22 | ? Right. He said, you can't have formation B. You |
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| 158:26 | if I mean, formation in general you know locally a is usually older |
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| 158:33 | be, you know, there's a , be above a bolo, be |
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| 158:38 | a bolo, be above. But you extend a into here, then |
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| 158:44 | got a above B. And that the law of superposition. So he |
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| 158:48 | the best way to solve that is is to look at the point where |
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| 158:53 | sandstone pinches out and draw a vertical and call all the shale to the |
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| 158:59 | of that, simply sign into formation and the shale to the right of |
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| 159:05 | include that with formation A. So the formation boundary. Okay, this |
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| 159:15 | online there these issues and line the red line I'm drawing is the |
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| 159:24 | boundary. And so now wheeler and were happy formation B. Always over |
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| 159:33 | formation A. And they solved that by simply assigning these shales two Formation |
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| 159:39 | rather than a. Of course you understand, but there's no difference between |
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| 159:43 | with ology here to the left and of that arbitrary vertical cut off and |
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| 159:49 | paleontological content of these shales would be same. So now we've got a |
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| 159:54 | , same mythology, same uh but because of a pinch out that's |
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| 160:02 | it, it's arbitrarily assigned to be than a. Okay, that's the |
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| 160:10 | . He did explain the paper that he met this is a B a |
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| 160:14 | a B and made a map of . People might think that there was |
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| 160:18 | repetition of the units or thrusting. they were concerned that if they had |
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| 160:23 | fingering formations alternating in map view, might get confused and think that there's |
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| 160:29 | of the formations going on. So wanted to avoid any structural confusion. |
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| 160:39 | said, okay, maybe you prefer over the sand stones in that case |
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| 160:46 | got, you know, shale formation . It continues there, but in |
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| 160:51 | to not have a overlying B. draw an arbitrary line from the lateral |
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| 160:58 | out of the shale down and assign the sandstone to the right of that |
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| 161:03 | being included with formation A. So the formation boundaries here, that's the |
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| 161:10 | boundary that separates B from A. , so we've got formation B with |
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| 161:20 | red contact information A. You recognize the contact is Dia Cronus and includes |
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| 161:27 | vertical cut offs. Okay. But , you know, this is the |
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| 161:33 | area, the inter fingering area and you assign various ages to that. |
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| 161:42 | this is not wheeler's work. This how So the the Black Hawk in |
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| 161:49 | Gate, very famous units and sequence . This was a major stomping ground |
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| 161:55 | john van Wagner and the excellent research back in the early nineties or late |
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| 162:00 | when I was doing my PhD, were doing redefining the photography of the |
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| 162:06 | the book cliffs using their newly found photography, but before they had done |
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| 162:12 | , this is how the units were . Okay, the black hole formation |
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| 162:18 | a marine to non marine plastic wedge which we have sandy shore faces and |
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| 162:24 | overland by shales and they simply drew arbitrary vertical boundary. The pinch out |
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| 162:30 | the sandy tongues included all the shale that as part of the Black Hawk |
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| 162:35 | all the all the shell to the is part of the mcas formation. |
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| 162:40 | ? So the formation boundary is this here. So it's a horizontal line |
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| 162:47 | it's just sam line, an arbitrary off horizontal line. She's online arbitrary |
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| 162:55 | cut off and so on and so . Okay then they did the same |
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| 163:02 | the price for information. So they to sandy members with the shale in |
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| 163:08 | . But all the shale is continuous the man coast. They drew an |
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| 163:12 | vertical line up from the point where castle gate sandstone pinches out. But |
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| 163:17 | shell to the left. They included the Price river on all the shell |
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| 163:20 | the right. They included in the . Okay. The point I'm making |
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| 163:26 | is that much of this photography in world? Whether it's in the *** |
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| 163:32 | , whether it's in Saudi Arabia The US is defined using arbitrary |
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| 163:40 | That's how most of the photography that will read about in the literature is |
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| 163:45 | if you go to an area and formations to find most of them were |
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| 163:49 | using these arbitrary cutoffs, then this a really essential concept to grasp. |
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| 163:56 | confusing it, there is some logic it. It does create the |
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| 164:04 | We have got the same mythologies, environments of deposition with the same age |
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| 164:10 | assigned to different formations on the basis an arbitrary vertical line. Okay. |
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| 164:19 | this of course began to create on . The brochure said, wait a |
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| 164:23 | that that's the same fossil zone. the same mythology one. Earth you |
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| 164:27 | in a different formation. Well, there's an arbitrary pinch out below and |
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| 164:33 | don't want to have, you we don't want to have this, |
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| 164:37 | don't want to have formations into fingering back and forth. So we're gonna |
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| 164:42 | to define formations using these arbitrary vertical offs. And that is the way |
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| 164:49 | little sabbatical was practiced through much of 50s and the 1960s And even into |
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| 164:55 | 70s. And you don't believe all you gotta do is go and |
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| 165:02 | at the kind of cross actions that in literature and these are cross sections |
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| 165:07 | were in maori showed these are not cross sections, they're just showing how |
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| 165:12 | people's photography was, was was constructed on the concept that they explain to |
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| 165:19 | of codify the practice of the Now these are black and white |
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| 165:24 | Let's just focus on one of these that's this Middle one here. So |
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| 165:30 | it is all covered up. So can see what's going on. |
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| 165:34 | the bright Angel shale is in the Canyon, it's over flamed by the |
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| 165:38 | of limestone, which is the Grand . The prospect Mountain record site is |
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| 165:44 | the same as the tip. It's . And so these are the |
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| 165:51 | Okay, and you'll see that the now, here's where it gets |
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| 165:56 | The bright Angel shale is to the , then to the right, it's |
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| 166:03 | up into the chisel shale and the shale separated by the Lyndon limestone. |
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| 166:10 | lindens limestone gets thinner and thinner in direction and pinches out at that point |
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| 166:16 | . So what the little strategies have have drawn an arbitrary vertical line. |
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| 166:23 | . Based on the pinch out of Lyndon limestone to define the pl shale |
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| 166:28 | on the right and the bright Angel to the left, even though these |
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| 166:34 | are the same mythology deposing the same and have the same fossils. |
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| 166:42 | sir. Yes. So the reason this eventually cut off vertical line is |
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| 166:49 | joined is to prevent violation of the of superposition. And also because if |
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| 166:56 | had this is the bright Angel shale that is a bright Angel shale. |
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| 167:03 | , okay. Over land by the limestone or the mob limestone, they |
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| 167:07 | afraid that someone might confuse that with repetition and thrusting. Okay, what |
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| 167:11 | the argument in the paper? Okay. Yes. Here we see |
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| 167:16 | Pz limestone separated from the lemon limestone the chiseled shale, where the Children |
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| 167:22 | pinches out. The millet limestone is defined on an arbitrary vertical cut |
|
| 167:33 | I assure you. Most formations that will ever work within your lives are |
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| 167:39 | using these concepts. Okay, that's it's it's valuable to understand why and |
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| 167:47 | the units you're working with are named when you start redoing this particular sequence |
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| 167:52 | , you're gonna you're gonna start redefining a very, very, very different |
|
| 168:00 | . So here is another cross Right? So that's which one is |
|
| 168:10 | ? It's not on here. just matter. This is another another |
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| 168:14 | from from the wheel and Maori So on the top diagram, we've |
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| 168:20 | the little photography. So we've got , the Hanukkah formation, the contour |
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| 168:26 | shale. And we've got the Rutledge . The Rogers feel shell maryville limestone |
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| 168:33 | land by the nolo Chucky shale. , all these contacts are defined by |
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| 168:39 | shows um lines but the formation boundaries all defined on the basis of horizontal |
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| 168:47 | vertical cut offs. Okay, now the lower diagram we have uh, |
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| 168:55 | actual mythologies. So Wheeler used the lift awesome. Just means rock body |
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| 169:04 | characterize this complex zigzag e body of , that's all shale. And that's |
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| 169:11 | from this, this body of that's all limestone. Again by zigzag |
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| 169:15 | and lines that show the the the inter fingering nature of the faces |
|
| 169:22 | Sometimes these lime stones are bounded by , graphic surfaces and that would create |
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| 169:29 | he calls a little strom and sometimes are bounded by zigzag that he would |
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| 169:34 | that Eliphas own. We don't use terms anymore. Now here's what people |
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| 169:41 | think miss. Okay, the middle has the word little faces. |
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| 169:50 | And the concept of life prophecies in and Mallory's time is foundational different than |
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| 169:55 | you and I would understand if we a course with, who teaches the |
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| 170:00 | environments classes that still Bill Dupree, else teaching that in the master's |
|
| 170:09 | Yes. He taught the Trajan ist And so he taught you all about |
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| 170:15 | . Right? Yeah. So you , he would talk about delta faces |
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| 170:19 | flew real faces and deepwater faces. , that's not the way faces was |
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| 170:24 | in wheel and Mallory's time. so um, the faces are these |
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| 170:32 | here, 100% shale, uh, limey shell, the shady limestone and |
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| 170:41 | limestone. So these faces shale, , limey shale, shady limestone referred |
|
| 170:50 | the average properties In this case three added together. This little faces. |
|
| 170:59 | more, three formations with different mythologies together. This is two formations, |
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| 171:08 | whole locker and a slight, a bit of Nolan Chuckie. So the |
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| 171:12 | faces in, in Wheeler Mallory's time to the average properties of hundreds of |
|
| 171:19 | of, of several formations added We would never use it in that |
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| 171:24 | anymore. So we have completely abandoned use of the concept of literal |
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| 171:30 | We don't use it anymore. These days we would use little faces |
|
| 171:36 | in this lower context, but even would be fairly would be fairly |
|
| 171:42 | Okay, so the point of this is that we, much of the |
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| 171:52 | graphic record in countries around the world named according to this philosophy today, |
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| 172:00 | . Okay. And you know, been far too many countries and I'm |
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| 172:04 | , oh my God, you're you're using these outdated little strata. Graphic |
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| 172:08 | based on arbitrary vertical cutoffs, It's not going to get you where |
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| 172:12 | want to go. Okay. The of little faces represented the bulk average |
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| 172:19 | of several formations averaged over a significant vs the environmental interfaces concept developed in |
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| 172:27 | 60s and 70's that we teach in a praise environmental metamorphosis class. And |
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| 172:35 | course the little faces again were defined arbitrary vertical boundaries. Right? So |
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| 172:42 | face, the spanish were vertical. everything was based on arbitrary vertical |
|
| 172:48 | The definition of literacy, photographic units the definition of little faces. And |
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| 172:55 | didn't coincide. There is the formation doesn't coincide with the little faces |
|
| 173:05 | So then I asked the question, this cross section. And which of |
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| 173:11 | contacts would you see in a seismic in a seismic line? Okay. |
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| 173:19 | you'll you'll notice I've got a word here. Flags or reality. |
|
| 173:27 | I'll explain that a bit. The other thing that we are |
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| 173:33 | which took a geological cross section like see on the right, and I |
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| 173:39 | like this cross section. Now, he's got drawn here is surfaces. |
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| 173:43 | single line here is a surface surface , there's a surface there there. |
|
| 173:56 | . And then he's got these sequences , you can see A. |
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| 173:59 | C. And D. Okay. it's pretty obvious that sequence de is |
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| 174:14 | from sequence. See by what kind contact is that? What surface separates |
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| 174:22 | D from sequence? See and un and what kind of nonconformity? What |
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| 174:30 | of nonconformity? It's irrational. Also . Exactly correct. Angela. Very |
|
| 174:44 | work. Okay. And angular on and sequence see is separated from sequence |
|
| 174:53 | . By what kind of nonconformity. and the national. Exactly. And |
|
| 175:05 | be separated from your neighbor. I kind of nonconformity. This gets a |
|
| 175:10 | boring repeating ourselves. Okay. But what's interesting is here so here |
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| 175:21 | got sequence. See that cuts everything and then what happens here the un |
|
| 175:27 | stops and we can continue to trace surface and it becomes I got to |
|
| 175:35 | rid of that. Um Here we a sequence K. Separating sequence |
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| 175:58 | And it's un conform a little then becomes conforming which is my dash |
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| 176:02 | And then the un conformity picks up that rather than call that A. |
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| 176:06 | K. Which would make sense to . He uses an arbitrary vertical line |
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| 176:13 | the tip out of the un And cause that sequence are separating sequence |
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| 176:20 | E. Then a sequence end because in conformity pinches out but this one |
|
| 176:25 | so you'll see that he's got all vertical arbitrary boundaries separating his own conformity |
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| 176:32 | at the point where the un conformity into a corral of conformity. |
|
| 176:38 | The big breakthrough that's all made is simply continued the un conformity ease into |
|
| 176:44 | correlative con forms. And in doing so people just didn't pay attention to |
|
| 176:53 | because he put all these arbitrary vertical offs. I couldn't understand why he |
|
| 176:59 | these arbitrary vertical cut offs. Because 1989, The only paper I've ever |
|
| 177:08 | by Wheeler was his 58 paper. I started teaching sequence photography, I |
|
| 177:14 | back and read his earlier papers and ah he was married to vertical arbitrary |
|
| 177:22 | . Huh? That's why he drew these arbitrary vertical cut offs in the |
|
| 177:28 | . And it didn't make any sense anybody. So they didn't use |
|
| 177:32 | However, what he did do was uh the the the the how do |
|
| 177:39 | take a sequence of folded rocks and that into Wieder space? Okay, |
|
| 177:46 | I want to I want to review see a little bit. Okay. |
|
| 177:51 | Quincy has one two three four five beds there Here it's got 1, |
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| 178:04 | 3 beds there. and beds 4-8 missing here, sequences completely eroded |
|
| 178:12 | It's got bad. one 23 for five units 678 are missing. That |
|
| 178:20 | sense. Now these beds are Okay, they're folded. And what |
|
| 178:30 | santo's law of original horizontal Itty Remember that if it better is |
|
| 178:39 | what it looked like originally at the it was deposited. Exactly. |
|
| 178:44 | So in wheeler space we take that one and we draw it as a |
|
| 178:51 | layer. Okay then that too is a horizontal layer. Okay, that's |
|
| 178:58 | too. Then we have layer Okay. And 123. But then |
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| 179:05 | this point there is 03 is So four continues here. five, |
|
| 179:11 | little bit less than 678. And these layers are eroded in this part |
|
| 179:19 | the way of the cross section. we pick up some more layers and |
|
| 179:24 | eventually they're eroding completely away at this here and there it is. The |
|
| 179:30 | units are eroded completely away. Now law of original continuity says well but |
|
| 179:37 | may be eroded array but originally these were continuous so we so Wieder draws |
|
| 179:45 | this area with with vertical bars to what he calls the the erosion of |
|
| 179:53 | . So it comes from the word or vacuum. It depicts the area |
|
| 180:00 | the time strata graphic cross section that originally occupied with the sediments of sequencing |
|
| 180:06 | were later eroded away. Okay, above sequence. See you've got units |
|
| 180:20 | 10. And unit D. And Unit one pinches out here. |
|
| 180:27 | T pinches out a bit more. three goes a bit further so the |
|
| 180:31 | of D. Looks like that. and of course it's on lapping the |
|
| 180:36 | of C. Which is eroded. the assumption is that dash line represents |
|
| 180:42 | end of sedimentation in sequence. See then there was a period of non |
|
| 180:48 | . And then the erosion of surface the on lap of the of the |
|
| 180:55 | unit which is unit D. And wheeler restores sequence C. Which is |
|
| 181:05 | rocks that are there today in winter plus the erosion of acuity to make |
|
| 181:12 | thing because a hollow strom restored complete . Then. Now the difference is |
|
| 181:22 | could have continued his sequence to include correlative conformity. Just called all of |
|
| 181:31 | . See But he decided to have arbitrary vertical cut offs. So you |
|
| 181:36 | see Quincy sequence K sequence and the our sequence see. And people just |
|
| 181:41 | up right. They just couldn't deal all these arbitrary vertical cut offs. |
|
| 181:49 | so he explained how he produced See and then here on the bottom |
|
| 181:55 | his policies, drones or restored Okay. Now what I would do |
|
| 182:02 | say it, let's just keep that . Let's just keep that going. |
|
| 182:07 | is what I saw and did. let's keep that going and just call |
|
| 182:15 | sequence A the C. And Because that makes it much simpler whether |
|
| 182:24 | was married to arbitrary vertical cut And so he had this proliferation of |
|
| 182:30 | that became incomprehensible. And he loved vertical cut offs. Now this folks |
|
| 182:41 | a bit of a crisis. couple of things happened. There were |
|
| 182:49 | big breakthroughs and uh In the The first was the application of the |
|
| 183:01 | graphic microscope to the detailed examination of box. And that was pioneered by |
|
| 183:08 | Cronin who taught bob folk. It one of those famous photographers at University |
|
| 183:13 | Austin texas and Austin had bob Um I forget all the guys their |
|
| 183:24 | will come to me and Cronin was annoyed at wheeler and his ilk. |
|
| 183:32 | said strategy if he's a complete triumph terminology over facts and common sense. |
|
| 183:39 | moreover, There were two big breakthroughs the 70s. one was the application |
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| 183:46 | Petra graphic analysis of thin sections which with Bill Dickinson's use of compositional analysis |
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| 183:55 | sand stones to infer plate tectonic origin sand stones. There was also a |
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| 184:01 | called plate tectonics in 1970s that followed after Christine's work. And the there |
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| 184:13 | a Journal of sedimentary Patrol ology. are tons and tons and tons of |
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| 184:18 | on thin section analysis and environmental process analysis of sedimentary rocks and not a |
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| 184:26 | of photography was ever published in the of sedimentary Metrology. Now this is |
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| 184:32 | by S. C. P. . Which is a society of economic |
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| 184:44 | and mineral ologists. They're now called Society of sedimentary geology. So we've |
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| 184:51 | the name but we keep the call and In some around 1990, john |
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| 185:00 | was the president of S. P. M. And split. |
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| 185:03 | Journal of sedimentary Patrol Aji into an . And B. They now call |
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| 185:07 | the journalist Central Research and he had issue was diverted to sort of sediment |
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| 185:14 | and the B issue was devoted to graffiti. So all of a sudden |
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| 185:18 | 90s photography came back In the 60s 70s. It stopped getting paid any |
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| 185:25 | to, particularly at universities. Now johnny Bhattacharya to enter the picture. |
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| 185:35 | took my first geology course in graduated with a bachelor's degree in |
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| 185:44 | And the only of course I talked which strategy was mentioned was my final |
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| 185:50 | I took called the strata graphic evolution North America. And we mentioned the |
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| 185:55 | sequences other than that, I've never anything about photography. I left Memorial |
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| 186:04 | the post ended A I want to a PhD Which took five years Left |
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| 186:11 | 1981. And in 1984 I went grad school In 1989, Which was |
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| 186:21 | years after I've left memorial. I invited to go back and teach for |
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| 186:25 | semester that I was talking about photography all the geologists. Memorial said that's |
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| 186:31 | dead field. We don't teach that . It's boring. They refused to |
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| 186:36 | any photography. I'm like, what you talking about this? There's been |
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| 186:39 | renewal of interest with sequence photography. that you know that's nonsense. Those |
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| 186:44 | deny tectonics. They just they think is used to seeing. Don't waste |
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| 186:48 | time with that. So strategy graffiti characterized by endless debates about what name |
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| 186:57 | based on arbitrary cutoffs of a variety vertical, horizontal and you know, |
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| 187:06 | folks looking at composition of sand stones infer tectonics, they felt they were |
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| 187:11 | the real songs and all this graphic arguments about names, which is |
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| 187:18 | gobbledygook for stamp collectors, they would paleontologist stat collectors. You just guys |
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| 187:23 | want to name a new species, ? There's no science in that. |
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| 187:27 | paleontology has stopped getting taught at universities at the same time In the in |
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| 187:36 | late 60s and 70s, people began realize that calling Adding three formations together |
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| 187:43 | saying it's a lively Shaler Shaler limestone simply inadequate. And roger walker who |
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| 187:52 | with Harold Redding at Oxford University in with the Dutch Shell Research group, |
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| 187:59 | recognized that extremely careful analysis of sedimentary , italian and trace fossils could be |
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| 188:08 | to make much more subtle distinctions of environments. And you could identify cyclic |
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| 188:14 | in sedimentary processes such as upper coursing lobe switching that create reservoir ceo |
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| 188:22 | So there was an enormous Focus in 70's on on on on this extreme |
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| 188:28 | in auto gen X photography much, , much finer scale of detail and |
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| 188:33 | that have been imagined before with all brand new tools. I've been involved |
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| 188:39 | detailed analysis of sedimentary structures and and and trace fossils. In addition, |
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| 188:47 | was a huge emphasis on petra graphic in which the data was used to |
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| 188:53 | plate tectonics. And if you're an in the 1970s and you want to |
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| 188:59 | money from the National Science Foundation or Canada and you were doing anything other |
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| 189:06 | photography and tectonics or faces analysis, would not get your grant and any |
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| 189:14 | to try to do something with photography considered to be old, dead signs |
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| 189:18 | no value. Now it turns out Harry Wheeler had a bit of a |
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| 189:25 | . Ah I know a little bit Harry because he taught at Washington University |
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| 189:32 | way all all the way up until mid 70s. And Carl Sagan was |
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| 189:42 | geophysics professor that I worked with at University of texas at Dallas. Carlos |
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| 189:51 | away a few years ago. But Carlos uh and I worked together and |
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| 189:56 | worked and he had taken classes from and he told me he said we |
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| 190:02 | never accepted plate tectonics. And so you imagine being an academic in the |
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| 190:08 | the mid 70s and denying plate So Wheeler was a laughing stock. |
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| 190:15 | , now there are a lot I would say enlightened photographers like Rich |
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| 190:22 | ask with daniel Bush. Uh Frasier . They all worked at universities in |
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| 190:29 | middle of the United States. We're ut Austin Oklahoma. You know. |
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| 190:36 | so this this battle. There's some here. You have the leading edge |
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| 190:42 | in California in the East coast, got the Princeton's, the Harvard's stanford's |
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| 190:49 | the University of U. C. . A. And they were the |
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| 190:52 | lights of plate tectonics and faces Penny john at john Hopkins University's. |
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| 191:00 | then you've got these grubby oils photographers about genetic genetic increments of strata formats |
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| 191:07 | you know, and they were getting from your business and nobody paid a |
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| 191:12 | of attention to the work they were . Uh Ask with the bush. |
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| 191:17 | publishing papers and the American Association of geologists and those were ignored by the |
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| 191:24 | and west Coast academic people. I'll you a personal story. A colleague |
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| 191:33 | mine graduated with straight A's from Memorial uh john Carew. So when |
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| 191:45 | he easily could have been an he took a job with S. |
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| 191:48 | . Resources Calgary. And as I dearly beloved. They can use |
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| 191:56 | professor, charlie Hughes sent with a british class accent. How can you |
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| 192:04 | yourself and go work for oil What a dreadful thing to do in |
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| 192:11 | words, those left wing professors in east and west coast of North America |
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| 192:19 | your business. They thought it was money grubbing capitalist with no interest in |
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| 192:26 | best to be hysterically it off as as possible. And so essentially all |
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| 192:33 | interesting photography was completely ignored by a of great universities. It gets worse |
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| 192:44 | I joined the University of Houston and was at field camp teaching field count |
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| 192:53 | of the professors at your age, graduated from UCLA told me rather sheepishly |
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| 192:59 | john have never measured a strata graphic . Ever, never measure the strata |
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| 193:05 | section. That was one of the . We do field cap, you |
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| 193:08 | , we got the students invested, and then he said, you know |
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| 193:13 | U. C. L. We talked, we were taught that |
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| 193:16 | trickery is bullshit and we should never any time because it's just it's it's |
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| 193:22 | it's these idiots that think that it's use static and they don't understand plate |
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| 193:27 | . And so we were taught that anybody that does see crystallography is a |
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| 193:32 | idiot and should be ignored. He admit now, you know, because |
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| 193:37 | was having with me, he but now I'm hanging with you. |
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| 193:40 | I realized that maybe it's maybe there's a bit more to it than we |
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| 193:44 | taught at U. C. A. We hired that guy in |
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| 193:48 | 2006, So this is a pretty problem, right? And the textbooks |
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| 193:55 | the time, you know, when started teaching Photography and Southern Atala ji |
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| 194:00 | Ut Dallas, the textbooks had almost static profion them. So what were |
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| 194:07 | textbooks teaching? So this is a of the art strata graphic cost cross |
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| 194:16 | peter martini. It was one of first graduate students, one of the |
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| 194:22 | graduate students That studied faces analysis at in the late 60s and early |
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| 194:30 | And this was his, his strata cross section of the, of the |
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| 194:35 | around the Hamiltons Niagara area. And it's worthwhile spending some time to |
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| 194:41 | this. Okay, everything is a line. There's no client forms, |
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| 194:47 | no surfaces, there's no on It's just a little faces. |
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| 194:53 | not the little faces of of wheeler Maori. These are environmental little |
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| 195:01 | We've got the vertical bars that represent flats. We've got the fine staple |
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| 195:08 | represents distributor, very complex flu vital predominant. We've got the dash line |
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| 195:17 | represents sublet Toral shale and silk Then we've got the core staple that |
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| 195:26 | present represents Longshore Bar beach. Uh we've got the crosshatch, which is |
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| 195:36 | little unit here and that says bio and shale. So a bit of |
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| 195:41 | there. Now, what's interesting is at the legend here, very few |
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| 195:46 | these units actually even described the mythology . It's all environments of deposition, |
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| 195:53 | that's why I asked you when I about the sloth side. Can you |
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| 195:57 | the environments of deposition Because in the , that was how rocks were |
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| 196:03 | Not based on the mythology that was trivial. It was the environments of |
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| 196:08 | based on the sedimentary structures and key features from which the environment could be |
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| 196:16 | . Okay, that's the blue meanie the Beatles movie, the yellow |
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| 196:24 | Anyway, so I'm just kidding So, you know, Clearly in |
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| 196:29 | opinion, this was PhD quality work the 70s. It certainly was good |
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| 196:34 | know where these environments of deposition But the question is, how useful |
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| 196:40 | this? And which of all these ? Um lines would produce an image |
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| 196:45 | reflection on a seismic line through the . Now let me go 10 years |
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| 196:53 | , this is Galloway, Hobday and . Bill Galloway is a famous sequence |
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| 196:58 | trigger for faces analysis at UT Austin this is their correlation of well, |
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| 197:05 | through the paleozoic successions uh, in , you know, pennsylvania and stuff |
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| 197:11 | uh, I guess texas. And again we've got ah that we've got |
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| 197:19 | stipulates dominantly alluvial. The, the, the, the lighter Stempel |
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| 197:25 | mixed strand plane and flew viel, dash is floral dealt alec Deltek. |
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| 197:30 | block is shallow marine carbonates. Then got some coarse level down here and |
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| 197:36 | is a zigzag, not a surface be seen. And then we go |
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| 197:42 | the textbooks. So that's 81, skip 20 years. So I started |
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| 197:49 | teaching as professor in 1998 and this the cross sections that sandbox was using |
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| 197:55 | try to teach you as undergraduates at time what strategy he looked like. |
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| 198:01 | I looked at this and said, gotta be kidding. Don't know how |
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| 198:08 | guys are harry potter fans. But know this, this is my question |
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| 198:14 | strategic graffiti or flags. Right. these depictions have almost nothing in particular |
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| 198:20 | that that there's nothing interesting it looks that. The only stuff that looks |
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| 198:24 | that is arbitrary vertical cut off Right? So clearly The Strata Graphic |
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| 198:34 | sections have nothing to do with strategic . zero. So here we've got |
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| 198:41 | got We learned mallory in in the the in the 50s, Martini in |
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| 198:50 | 70s. We've got You're at Austin in the 80s or I should |
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| 198:56 | that the Bureau of Economic Geology gallery the faculty at that time. And |
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| 199:00 | we see these magnificent seismic lines with forms. Their is a shelf. |
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| 199:06 | is a slope, there's the basin the SARS Valley, there's some faults |
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| 199:13 | here. Thrust faults. That's that's forming this nice shelf smoked quantifying |
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| 199:25 | All these beautiful reflections that are bouncing surfaces and there's not a clarifying to |
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| 199:32 | found anywhere in these cross sections. is a sandstone to show that this |
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| 199:37 | have clown forms in it. It look like that, but not a |
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| 199:41 | for him to be found. So is the seismic seeing that the that |
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| 199:46 | state of the art geological cross sections utterly fail to image or convey. |
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| 199:56 | , something is missing in these textbook of photography That was still being taught |
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| 200:03 | the way up to the 2000s at across North America. But when I |
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| 200:08 | teaching sequence photography in 1998, I told to go away and I'll do |
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| 200:14 | . That's not strictly true. By 98 people houses made. It was |
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| 200:18 | to it. There was a lot pushback from academics about sequence photography. |
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| 200:25 | to conclude Larry slaw sauce co supervised bale, peter vale. They'll really |
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| 200:35 | attention to this loss and realized that his ideas could be part exquisitely to |
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| 200:41 | interpretation of seismic data because of the need to transition armies from coal to |
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| 200:52 | fuel, jet fuel. Uh, , the, the, the, |
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| 200:55 | hydrocarbon era was introduced that resulted in explosion of subsurface seismic data. Seismic |
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| 201:05 | was originally developed on the basis of used to detect submarines in the World |
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| 201:11 | Two. Specifically the wolf packs. we're trying to cut off the supply |
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| 201:16 | from north America to europe and particularly , to supply the diesel to Churchill's |
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| 201:23 | and the Germans trying to cut off diesel supply lines to stop that oil |
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| 201:27 | getting to England. That allowed the navy to rule supreme. Okay. |
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| 201:33 | of course, in addition to finding , the seismic data, they realized |
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| 201:38 | continuous images of the subsurface fill of basins and in particular anti cons and |
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| 201:47 | . That allowed them to identify prospects areas previously not accessible by just mapping |
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| 201:54 | surface. Now, vail and his went one step further. They realized |
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| 202:01 | there was strata graphic significance in addition structure. And they apply these old |
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| 202:08 | of wheeler Burrell Blackwelder, really old to new data. So really the |
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| 202:16 | data graphic revolution took a very old and they finally found found data that |
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| 202:22 | could be applied to easily. But was difficult to apply a lot of |
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| 202:26 | sequence strategy for concepts to the kind outcrop little faces analysis that was being |
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| 202:32 | in the 50s, 60s and And that of course an Exxon in |
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| 202:38 | because of the size of the company be able to compile seismic data from |
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| 202:43 | around the entire globe. And that signs of seismic photography. And then |
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| 202:49 | geologist wait a minute. Maybe we apply these concepts to our well log |
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| 202:54 | and do even more refined mapping of . So parents and that of course |
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| 203:00 | now become sequence photography. Okay, we are done with our morning. |
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| 203:07 | believe it's a Should be about about , 20 to 12 there. I'm |
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| 203:14 | going to do another lecture now, because I need a break and then |
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| 203:20 | have lunch. So um let's meet again at It's 20 - one. |
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| 203:30 | time you want to get back? an hour hour and 10 minutes. |
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| 203:36 | do you think? Let's make it hour and 10 minutes. Okay. |
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| 203:42 | uh so that's it's 22 now it's to be 10 to 10-1 your |
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| 203:48 | That will be 10 to to my . Is that right? Yeah. |
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| 203:53 | then we'll will do a seismic, lecture. Then I'll do an exercise |
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| 204:01 | maybe one more lecture. We'll see the day goes. Okay? So |
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| 204:06 | a break. Have a good break we'll see you guys after lunch. |
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| 204:09 | ? See everybody. I'm just gonna |
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