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00:00 Well I want to talk about sediment bed forms and the resulting sedimentary structures

00:10 because this is really the basis for to create the architectural elements by which

00:17 going to Uh huh be able to deposition arts. Okay, so this

00:24 one of the reason why I say the exams are slightly accumulative because this

00:30 the background material you'll carry with you transfers waves if you like. Are

00:37 in any variety of things. Air , air, air of sand,

00:43 or sand. This is a repetitive of fluid dynamics. And we are

00:50 interested in water over saying so when look at a typical transfers platform across

00:57 , we see there's several components to late the right height, the slip

01:05 or which is the side we noticed breakpoint where the sediment basically spills over

01:13 avalanches. Isn't necessarily at the So there may be on from summit

01:21 Boy and some presentation we have so which in some critical followers its own

01:30 . Of course it is. Uh would be designed deposition. We'll talk

01:38 about the flow velocity here we can out that you see the water,

01:45 water be pressed last year. increase the Maria in phase motion.

01:58 this is a really huge Exactly. , so you can see that you

02:04 exaggerated human. Now that's the cross . The plan view gets more complicated

02:15 this particular case. It was very genomic. Oh good. And this

02:23 uh wedding ring. He wasn't the hacking. Uh not a good

02:31 Uh He did graduate apparently is still uh pardon? Still married. I

02:39 so. Uh I did tell me was authentic. Uh and we can

02:45 look at the map form of ripples ancient rocks, which to me still

02:52 a bit amazing that something is ephemeral a rippled surface could be preserved.

02:59 they're actually not that uncommon. And uh in this particular case we have

03:05 is a different orientation, different different shapes and cemeteries. There's just

03:12 lot of information that we can actually into the rock record if we understand

03:22 , I can say. And one the things we recognize is that ripples

03:28 by hate direction parliaments. Well, , then ripples form like austin

03:37 Wait, right? Also towards wait, so this would be an

03:42 story ripple, wow. When uh if you like. That's a current

03:51 . We actually, we'll see when look at coastal environments on various combinations

03:56 Curtis. Wait, the current might a long term current and the way

04:01 being generated. We also look at impact flow ferocity. We're really flow

04:11 is measured by what everyone measured with to ripple fault. We go from

04:18 motion to motion First reform straight linear first in two dimensions, there's no

04:30 but notice that you get a warrant stimulus. There's a whole world fascination

04:38 not much except that basically get one regular than the blackout. So what

04:45 see in this transition is a move motion. two dimensional recalls three dimensional

04:55 to play with it. And we've this for a long time. We

05:00 see it in waves as well as currents. But I'm going to focus

05:05 uni directional counts Now. The other is, and we look at

05:13 ripples are the only transfer of Tens or not. Mhm. And

05:21 Mhm. And yes the waves like following just feeling, wait, what

05:32 you think ripples or the order? centimeters. You hear about wow waves

05:42 ripples of more than a meter. huh. The heights the same thing

05:50 ripples and things that don't use another . So there really is a fundamental

06:00 between ripples and dudes. Even though is a morphological similarities, one of

06:07 big distinctions and I'll expand on that ripples do not scale with depth.

06:13 can see a ripple. So okay this James escaped well. So the

06:22 the data. But I want now do see some dudes very rarely.

06:30 we do see dudes in some basic . It goes back to the fact

06:35 sometimes the depth is not water depth it's adapted with a thickness with.

06:43 with that you get the sandwich Yeah, both with respect to hike

06:55 wavelength. You get a similar separation the aeolian reference nearly. Yeah,

07:03 won't really be talking about this right but this separation concept, it's fundamental

07:11 sedimentary bed forms and a variety of . Now dudes like rip tend to

07:22 from straight prices in particular. Three delicious with increased philosophy. So

07:30 see that the plant forms vary in acts for the ripples and dudes.

07:38 straight question written vs The three of scenes basically lower velocity the full

07:50 . And as we'll see in a , seven infrastructures are similar as

07:55 differing only escape. Now, if look at the flu data, we

08:03 that no matter what death is The single asking. We go to

08:11 So this is uh at least Within 10 m water depth beyond uh this

08:21 hope so it's death. And the thing we see is we often will

08:30 superimposed. Um I think he's pointing wedding ring? Wasn't sure. But

08:39 are ripples down in humans. And there's ideas notice in each case

08:45 not straight president. They're also not scoops and scallops. So this is

08:52 the lower part point. So these common New Henrik. I point worth

09:02 . Now here we also see dudes they're beginning to be claimed out.

09:08 just as we saw earlier, the that you could have ripples Going into

09:14 DS and it's claimed out but no had dudes, they begin playing down

09:19 well and we came dunes occurring at scales. This is a very three

09:28 type of dude uh elongated scallop. doomed press. I'm very old and

09:37 can't really tell what the scale is until you man, you're playing and

09:43 that these things are meters deep. other thing that's interesting here is that

09:48 just said that the height of the is proportional to the water death.

09:57 depth is typically 3 to 10 times in the height of you did

10:03 That implies this water was really This is the Yukon delta and these

10:10 reform during breakup dish where there's a flood that comes down every spring when

10:16 ice breaks. So you get a grant spikes like this drops down like

10:22 , leaving behind these really big And what that suggests is that this

10:28 be one of the things. We for them trying to distinguish sedimentary structures

10:34 point bars formed by different types of patterns. Okay, so if you

10:41 this very large scale dunes trust The upper part of the dune,

10:49 tell you something about the size and of the hydra graph as it varies

10:54 clients. Uh, here we've this is actually entitled and these are

11:01 , but they're, they're currents that been organized the ebb and flood

11:07 So the unique correction Here we have dudes and a length of about 10

11:15 . Um, so, uh, can get these features and all sorts

11:22 depths and their patterns are really quite stick. Now you've got this in

11:31 notes. But let me just ask many of you are familiar with the

11:34 regime concept. Well, um, , down now. Okay.

11:45 I want to say shame on you it's not your fault, but it

11:48 a fundamental concept that has really changed way we look at an interpret sedimentary

11:56 . Basically it was derived mainly from done in river river where they saw

12:06 once sentiment got into motion lot of griffin, what did your plane that's

12:14 ? Can you get where is the ? And it also delineates between these

12:24 bit lower flow regime and the transitional bet forms associated with comprehension. Why

12:37 they called they call anti dudes because migrate in the opposite direction. Whether

12:44 uh informed my great in the opposite expect. Okay, migrating strip.

12:51 start to get you. Now there's sorts of characteristics associated for for regime

13:01 the first I'll point out is that are more or less than uh some

13:05 super criminals. So that's the first back fruit of the flow regime features

13:13 are food numbers greater than. there are also some between this continuous

13:22 set of the pen. This diagram out of date now is beginning to

13:32 dunes. We realized that goes back discontinue but for playing that is continually

13:39 motion ripples and news their emotional on backside store concentration increases with increasing

13:52 Yeah. And water services. I'm business how to phrase this is needed

14:06 change that. Uh, so we're to see how the hydraulics of open

14:16 flow is beginning to control the bed and ultimately sedimentary structures. Now we

14:24 able to do that to a large because at the same time,

14:30 workers were looking at the river on river, we had mainly engineered

14:37 and geologist working influenza car on It's a big loop so they could

14:44 dunes. Things that earlier work couldn't . And what they did is that

14:52 the most part they saw the same , simple cripples and danced again,

15:02 out dams. Find there's any games notice it. This is that hydraulic

15:12 talking about with increasing floated. Where that? I'm not just now.

15:23 problem is that the flow regime concept initially not because they don't feel the

15:36 immediately, but they cannot control actually they had, they were measured ferocity

15:46 floods, but the gun change with flu bed in the chamber inside.

15:54 so what happened is, it became that it turns out that the flow

16:00 concept was only good for certain brain when you got into Porsche grains last

16:11 . Mhm. So the first thing ripple, claimed it the lower plane

16:17 then those went into dudes and notice Preston two dimensional. The threat which

16:25 you complain to get over down here motion ripples, ripple field or straight

16:34 it too. Same to the treaty then into mega. No measurable.

16:44 got to use it. We don't any futures. So they went into

16:52 tv three. So this is like that you got it. This we've

17:00 the dimension of rain site. So we have a two dimensional Goddamn vs

17:08 one dimensional. Now look at the here. Uh huh. It shows

17:16 we're gonna have small crane you got . Except that's not really true because

17:24 did more and more work we realized just this once an upper brain size

17:31 ripple if there was a lower. you find anything you don't get this

17:41 course. Right. Sandy and this or will we change is highly holds

17:47 the president. It is one of things you need to having the mind

17:51 all times. If I ask you draw this diagram maybe by next fall

18:00 couple of differences here. Sand Dudes earlier mega ripples, many ruffles

18:11 gone now sand waves are gone there to the news. These are typical

18:19 . So this is now beginning to . Yeah. So what can we

18:25 about ripples? Well they're formed brain less than about second. Yeah,

18:34 turns out that's the break between hydraulically and hydraulically well so mm rebels tend

18:48 be associated hydraulic smooth out. In what happens is in order to get

18:56 fine grained sands moving. You've got break up that disk of subway.

19:02 it all it takes is one little bump people and that's enough to initiate

19:11 . And ripples form instance if you at the flu and you watch it

19:15 goes from flat to rip just like because the ripples are what are basically

19:21 up. This is like creating eternities height less than 10 cm in depth

19:31 D. To three D. With lost wavelength. Uh A 1000

19:39 Don't worry too much about it. they're smaller waist. Now there's another

19:45 that you just kind of learned about last 10 years. So these are

19:51 . Yeah these are kind of like and genders but these are discontinuous cripples

20:00 mud flocking. Remember I said that auctions and side. What about side

20:14 And these people migrate avalanche of This and there can they actually have

20:29 for centuries. Just like a record . And This is a picture of

20:45 . And the point here is that they're compact and they're hard to see

20:53 the in him with the ball animal patients groups. But it's an

21:05 So we can't see it has preserved protected as easy because of compassion.

21:14 we look at this and we what we assume? We assume this was

21:18 of suspension. But what it really a series pro grading but trips as

21:28 . Huh? It's a very different . Okay, what about dims?

21:36 . Uh, for sure. Great . I am not tension hide any

21:44 with two d, 3 d increases wait for an interesting stuff. So

21:52 of your review questions for the exam be compare and contrast rubles induce or

22:01 are they similar and how are they Now? There was a lot of

22:08 as you might expect between mainly due . Yeah. So five people want

22:18 keep it all going to be doing sand wave no matter uh, we're

22:26 standardized. Yeah returns bigger. So are just standards. You don't

22:36 They just know where to go to that there are some dudes that have

22:41 over 100 m heights of over Yeah. Uh huh. Also Because

22:53 scale with death. We use this 10.30. Death turns out I'm going

22:58 talk more about that because there's a more discussion about that in recent

23:06 Okay. So here's a typical blood And we're gonna look at definitely I

23:12 this is santa, santa river So we've got some small guns

23:21 Oh, you mean that's bigger So many questions. Are these large

23:28 very large dudes? Oh, what they? Something else? Um,

23:38 they are superimposed excellent. But what you call these large students? Union

23:43 ? Yeah. it turns out that are there is a really confusing concept

23:53 distinction person between dunes and books and are just the things we've been talking

24:01 Children's but a unit bar is another feature, transfers future. Uh huh

24:14 can actually fill the flow. So depth is limited clothing, it can

24:21 much larger than do. And these the mid channel bars that we used

24:29 thinking in british troops. But they're he knows it's so important. Confidence

24:40 and for the longest while when I see these in the rock record I

24:46 just think they were large. It a while for me to realize I

24:53 looking at apples and oranges. There dues and there are unit box and

25:00 talk more about those distinctions a little particularly talk about fluid because it's So

25:07 is it that controls those bed Well, there's some fluid stuff and

25:11 particle stuff. Close strength stuff and there's a lot of variables. And

25:18 are the variables that all controlled and but let's Uh huh. Make it

25:27 . I'm size but all the fluid here on sediment variables here. Water

25:32 here. This further or say let's fresh water. 20°C that use

25:41 Uh huh. So what that does gives us a settlement an example.

25:49 strict favor. And let's forget about for a moment. But think about

25:58 many flow velocity. I said Mhm This is this concept is two

26:08 bed things which is the successor to in concept of it's really what we

26:16 today. This geometry with no motion . No more cripple prepare complainer,

26:33 . It really pretty much the same we have here in europe. We

26:41 use this gym. So those are based what's missing is the effect of

26:52 . Now. Okay, this is uh it to the news. Three

27:00 . Mhm. But I want to out on what they call in phase

27:04 or any deals they take out. don't have to be when the water

27:17 are more than this. We don't any any get at least as we're

27:26 with me with typical floating issues. things like God density currents. So

27:35 is an effective float. Yeah. In fact we could look at flow

27:43 and flow velocity difference, range And so one of the things I

27:52 take time to ask you which is course is rate size. And I'm

28:02 say that if you're looking for the of the brain size, Look for

28:08 Children. This says they go from motion lower player than excellent. It's

28:19 finest great size for young. No ripples. A pleasure if you want

28:31 look for medium grained sand. This for the you notice that Uh huh

28:40 really only the anti still one that see on magic uh that you see

28:50 lot of very issue. Now some is based on field, there is

29:05 . So you got gaps and lots time. Some people have tried to

29:12 this to reconstruct slow death. why would you want to do

29:16 Well, you want to if you to understand the paleo hydrology of your

29:22 . Slow death is a critical in is fundamental to the focal method.

29:29 I talked about earlier of reconstructing the . Gm budget upset about it.

29:40 problem is, well, we don't is the very first of all Mr

29:50 . He said it's very very Just too much exploration. You've got

29:58 he wants as a confidence velocity. , you probably with didn't cross

30:10 You're probably from one meeting 40 each . That doesn't help. Uh You

30:17 see this diagram and this concept used try to reconstruct a slow death.

30:24 lot of the human pupil we don't . Well first there's not a lot

30:30 changes. Blue, yep. Uh . Uh The only thing I

30:39 you know this didn't face. back. Uh huh. Yeah and

30:54 is the hiding games versus the depth the broader, wow, cool.

31:06 their existence. No, I believe . Yeah, there are. We

31:13 looked at that. We don't have good damage Even after 40 years,

31:20 years ago. I talked about that here between hydraulically smooth. That's a

31:30 thing that we can take back into uh, into the field. They

31:35 importantly, I think that this than . If we see mhm Marshfield ostentation

31:48 pretty much so wearing this here. see just by looking at sediment

31:59 we can say something about the Now going back to look at the

32:04 plane, you're of course it rained equipped. It turns out they're not

32:14 playing debts. They're really low amplitude were migrant. And so this is

32:24 that would look like if you took snapshot. Yeah. Um Hide is

32:38 New York 5 - 10. They're water depths. Uh here we see

32:47 with time as the doom passes a one. And they give us something

32:51 this. They give us cleaner but it's not due to just

32:59 Uh it's due to the migration of low amplitude bits. Well, look

33:08 this later where we'll call this with of these translates? Well, that

33:14 stratification due to the translation that notice here we got out of phase

33:33 . Yeah, here we have in . Well, I said earlier uh

33:41 credit, we actually have two kinds planer betting which is defined as recognized

33:55 lower playing. You're an upper Mhm. Upper player like lower player

34:02 largely the result of migrating logo. logo. Very hard to say you

34:08 really see the meeting the profit rather the translation of those migrants. Low

34:16 methods. That's is that right now we increase the velocity Within the super

34:33 12 start personal standing ways. then they become unstable. It begins

34:44 . We've got breaking standing waves, quality jobs did she? And

34:51 We'll see later. Steps were really is the area that's been focused on

34:59 recent expanding this both influence and then . So what are you saying that

35:06 floor regime increased? Uh huh We're preventing upstream migrations. It's another world

35:17 that upper float. So this is latest of the bit for body we

35:30 so again, it's the limited flow 100 because this is the one I

35:38 you had in your box corporate Oh is that to the three treatment

35:51 the player and the news. We of pitch out of the grain.

35:55 to shoot okay with something like The any days are at least in

36:17 . Typically a few centimeters time wavering me around me. Okay, low

36:25 here they are kind of standing You're kind of breaking the double points

36:34 these are the ripple forms that we . These are the candidates that typically

36:39 on beaches. The most common place see an anti dunes on beach,

36:45 velocity, low water depth. My number upstream migration. So here they

36:56 dipping matters. These were stable and do. They get unstable before

37:07 right, get more depth. You see the beginning to break right here

37:15 students. Uh you get more and kind of motion shape. I'll talk

37:21 about this sediment instructions. But the of the bed for waiver and getting

37:28 and bigger as we get into higher . And the significance of the high

37:35 jumps are getting more and more significant we get into the fucking moose

37:42 we're looking at those mainly through But we're seeing the sediment to record

37:48 equivalent in sediments as well. And you look at the same side

37:54 but it's great some of the Let's endless submarine canyons on the order

38:02 the kilometers heights, tens of Small ones on the border 1 5

38:13 . God, but these are comparable bigger dooms that we get and rivers

38:23 we can get these in big Yeah. And here's what those way

38:29 what you can speak. He smells and look what happens. Talk the

38:44 , the seat side deposition. These version definition. So the fed fullness

38:55 migrated the depths or free what is upstream christian. And that whole for

39:07 type of steps in your orders of difference. All right. I'm gonna

39:15 here because it's convenient place to stop lecture. What I want to do

39:20 now begin to look at the sedimentary that are formed under the different bed

39:26 . And we will start that after . So let's stop their voting

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