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00:00 Yeah. Okay, okay. Uh we've looked at um the fluid processes

00:12 are causing sediment transportation definition. So I want to look at now are

00:20 the bed forms that result from And then the second part of this

00:25 will be on the sedimentary structures. , when we look at and and

00:31 I say bed forms, I'm I'm speaking about Sophocleus uni directional thought,

00:39 means I'm not dealing with waves, not dealing with wind, I'm not

00:43 with sediment to gravity. Okay. of those will have their their

00:47 Okay. And when you think about , trans verse, bed forms said

00:52 angles to the flow direction occur and all fluid, the fluid interactions from

00:59 to air, sand, water to . I mean these are pretty common

01:05 and to be honest, we don't even now have a good explanation for

01:13 they're formed in detail. What we do is describe when they form and

01:21 conditions from that. So you do you can do. So here are

01:30 inter directional rivers. Okay, now problem is you might assume that why

01:39 with ripples, their ephemeral forms, see them changing all the time.

01:43 the reality is they are often preserved the rock record. In fact they

01:51 sometimes be preserved layer by layer by . And so although it seems like

01:56 are very fragile kinds of features, have a survival instinct that really works

02:05 well for them. So we can a lot from looking at the morphology

02:11 the ripples. And so one of things we see is that there is

02:15 complete gradation from oscillate Torrey ripples form waves, which frankly, we're not

02:20 to worry about now to uh combine . Where's waves and the current to

02:27 current only. So we're only interested current form ripples at this point.

02:36 what we we've seen is that the plan view changes. Is you increase

02:44 strength, however we measure okay? they start off pretty straight, press

02:51 pretty linear and then as we increase motion uh or at least certain grain

03:00 , we go from no motion to to plain debts. And the ripples

03:07 change in morphology from pretty much straight uh to kind of elongated sinuous,

03:16 made ripples. And so what we is we define these transverse forms as

03:23 dimensional or three dimensions. Uh Two , are straight crested, three

03:30 are much more sinuous and planned this for both ripples and deuce.

03:35 so it's probably a good time to between ripples and dunes. Uh The

03:44 thing to know is that ripples do scale with depth dunes. Do scale

03:50 death. What that means is the the water, particularly the chance,

03:55 higher the dunes? Or is it matter what water depth you're in for

04:03 , they're gonna be the same. other thing is they differ in terms

04:07 height and weight. The short of is ripples are smaller. The

04:11 but more specifically, we tend to ripples rarely over about seven cm 8

04:20 high and rarely over a meter and typically less. Okay. Uh Or

04:28 typically since. So if we were kind of plot that wavelength versus

04:38 you see that there's this critical break , 80 and leaders. Um 10

04:56 on weight. I'm here down Now we see this evening with the

05:06 . We see this more so even the only. So we sometimes uh

05:16 sloppy and the way we describe ripples dunes, they are very different

05:21 both in terms of measures uh flow uh as one of those dimensions.

05:31 here we see this transition from two . to three d. D.

05:38 with increasing flow of lusting. And we see it looking not only at

05:44 plant form but the sedimentary structures. so we'll come back to this in

05:51 second part of this lecture where we at how we can reconstruct that form

05:58 sedimentary structures short of it is uh straight crested bed For me, the

06:05 or dunes are gonna have a difference section and strike section uh than more

06:14 or three. Uh doing bed for dimensional bed forms. So here we

06:20 that when we look at blue down what we're doing here, the increase

06:30 lawsuit you go from to just as going to the report. So for

06:45 of these hand, first bed forms and dudes, uh there's a if

06:50 like a low velocity form and high for minutes. Gradation. Okay.

06:57 we also have superimposed platforms uh here have uh more or less three dimensional

07:07 . Look at the wavelength here the and superimposed on that or little three

07:16 ripples. Okay. And so it's uncommon in certain grain sizes and flow

07:23 to get the superposition of dead forms therefore the superposition of sedimentary structures.

07:33 , I know this is one of students is working on the masters.

07:44 let me, okay, let me a question. May have life.

07:53 , would you say these are two . or three D. Bad

08:04 Hey, what do you say? D. Okay, what about

08:16 This is an oblique aerial photo. . Look at the chris.

08:33 In fact, we've gotta scour pit being filled in by slip face.

08:38 you think they're dunes or ripples then . Well, what's your guess You

08:49 ripples do. Absolutely. But This is kind of a leap of

08:56 , but this is from an Their large. Absolutely. Okay.

09:03 and here's what it looks like on ground. Okay. So uh these

09:08 really big ripples. I mean I'm big dudes. Uh that must have

09:14 because remember I said the they scale water depth they missed formed when this

09:21 was at a very high status, Yukon River. Um and uh it

09:27 really peaked floods during I Sprinkle well is one of the ways in which

09:33 hydroxy fee or hydrology uh of the flow is conditioned by climatic conditions.

09:46 is high latitude ice breakup and it reported in bed forms. These are

09:52 thick bed forms reflecting very high Okay, here's a this is a

10:01 earth shot, but again, it straight Preston two D dunes with a

10:07 of about 8 to 12 years. I mentioned this, there's every once

10:11 you'll see a um somebody say that Preston or two D dunes don't form

10:17 nature. Of course they do. said that has never looked at google

10:23 . Okay, so it really brings to the flow regime concept. Uh

10:30 , Hayden, when, when you at L. S. U.

10:33 did they talk about the flow regime with respect to uh 407 infrastructure?

10:46 , what do you remember anything about ? Uhh days, 11,

10:53 13 years ago. Okay, well, fair enough. But this

11:08 hugely important. And this is it says that, you know,

11:17 ripples to dams. That is no ripples to due to the and that

11:26 transition from dunes to flat band more less the transition from what is they

11:33 as a lower floor, the upper ownership and more specifically, that's going

11:39 be um low crude numbers. I . Now there's a couple of things

11:46 note here. This particular concept was really as a one dimensional concept.

11:56 I mean by that is the only his flow velocity. So this is

12:03 change in bed form in sedimentary structures with changes lost the it was described

12:16 by workers with the USgs who are on the Rio grande river of medium

12:21 sand. Uh and and they described in great detail. For example,

12:29 noted it alone. He the purpose out faced with death point.

12:39 Upper flow regime, the circus was phase for benefits. We went from

12:45 continuous to continuous transport. Now that's true after about here's a from higher

12:57 of increase in concentration in face All of this sequence was done based

13:13 few studies from but medium resale but the same time at Alliance, I'm

13:23 colorado State University. I had a plume and the Engineering Department was looking

13:29 sediment in this blue 150 ft long they came up with more or less

13:36 same idea and washed out transition going station anti news. Now hydraulic jump

13:54 into its court. Now this portion , the higher velocity of authority and

14:04 really weren't described in that field set the advantage of the flume studies.

14:11 Now just imagine that hydraulic we're talking here rather earlier with respect to going

14:20 uh screaming flow to tranquil flow. , now the field study looks like

14:32 . This is what the tomb study . They were able to experimentally vary

14:40 grain size distribution. And they also that both dunes and ripples, there

14:49 a straight press city 12 seamless three . High velocity. Again, I'm

14:59 use velocity just because it's a shorthand all sorts of other measures will

15:07 Now, what they showed that was shown why is what happens when you

15:15 into safe? You don't have any instead. You've got the first motion

15:22 you plane beds, it goes straight it. No ripples at all.

15:33 , they all go into playing that . But now let's look right

15:42 What this study did. This first flu study assumed that you went from

15:52 that even in front of good it turns out you don't, as

16:08 began to use find a great they realized that there in the brain

16:18 and grace. No. Now we're that dunes are restrictive and said,

16:34 course they're being, let's say that little less thanks. And that ripples

16:43 restricted to about seven. Unless and only queen which immediately expand is what

16:58 for their. Yes, sir. now we've got two dimensional bed

17:05 Doctor showing the effect of increasing flow on different range sizes. A couple

17:17 other things knows there's two flatbeds that . Now all this lower planer,

17:26 upward. Uh No, it's also have sand wave versus dunes. These

17:33 now two dimensional three. So the of the fields isn't changing much,

17:41 we're beginning to refine what the bed are looking like. Now let's look

17:46 this bed for not from plan cross section. And one thing I'm

17:52 is that uh the upstream as relatively maximum velocities and as it converges towards

18:04 crest. So we have converging flow and diverging flow here. So we've

18:17 acceleration, approach, deceleration, The other thing about this is that

18:25 you look at the velocity profile, actually those stream lines are coming out

18:32 this and they reattach right about So there is a zone of

18:41 This kind of a Yeah, river shadows up and so there we can

18:52 have reverse flow down here. And that reverse flow. If the

19:00 of the bed form is large we can actually get ripples migrating upstream

19:04 the trough, but we'll see examples that. Yeah. So it's a

19:15 confusing makers, we talked about how is higher energy and so we have

19:21 erosion. Yeah, but based on illustration, it looks like sediment build

19:27 here versus this to indicate where the we were to look at this in

19:40 to it would look like this second three. Okay, so it is

19:54 here and it is depositing here. and the other thing I just point

20:05 there's a little bit of a difference the summit point and the brink

20:10 We'll talk more about that later. brink point is where it starts the

20:16 . So there actually is a zone the break point in the summit point

20:22 you can actually get some horizontal lamination would be like the top set.

20:28 . Yeah. Okay so in this is what you need to remember

20:37 . Don't worry too much about wavelength but everything up there is an important

20:45 to remember because I may ask a like compare and contrast ripples and tenants

20:52 this is half much of the answer within the last decade and really five

21:04 we're beginning to realize that um we're to realize that mud can be transported

21:17 ripples. Now that's that seems really . I've already said there's something odd

21:24 getting mud in motion but there are little mark can like ripples that are

21:35 but not as individual part in It is saying clay populated clay parts

21:46 have a dimension The Moment five and . Even though they are individually simple

22:01 . Now you can see that they series of slumps downstream side. And

22:12 this is what they have to look . And so there is at least

22:18 potential for these third ripples to be shale record. Uh This is what

22:32 want. So this is a non uh Margaret. Now the problem is

22:49 . And so um this is that look. Not that this is a

23:00 the reason that's important is it gives a very different view of how some

23:06 rocks are deposited. The standard orthodoxy that mud is deposited from suspension very

23:18 energy. But now it could be high energy with blood being. And

23:28 it's causing us to reinterpret the muds you can see, I I think

23:33 pretty easy to see how subtle those are. You don't see it till

23:42 looking for when you look for You realize that a lot of what

23:47 thought of as paper thin laminated bloods in fact repeated muds. Alright now

23:56 contrast that with dunes, as I earlier, they don't form in fine

24:01 sand, they're larger. Their height with depth, doesn't like ripples like

24:11 two D. To three D. increasing velocity and the wavelength increases with

24:16 velocity and brain cells. Now, other thing that we have kind of

24:25 agreed on is terminology and I don't you to remember a lot of the

24:33 , but I do want you to that there is a terminology for distinguishing

24:39 small, medium large and very large . So basically students and that you

24:45 where to find it in your Uh because too often we just kind

24:52 say, oh they're big. I'm call him large. I don't

24:56 it looks like medium to me. those are small. You are saying

25:01 big ones, uh we need a criteria and uh, we can't settle

25:08 this. Having said that a lot discussion. That's all right. And

25:15 of the big discussions I'll bring up just a moment. That's what we

25:18 the unit bar. And so some what we used to call large or

25:24 large dunes turns out aren't really dunes se. But hold onto that

25:31 let's look right now at a point deposit. And uh we see here

25:39 lot of small dunes and then these structures. And when I first started

25:50 this course I called these large gyms very large. Uh It turns out

25:57 are probably what I'm going to describe unit bars. Okay, now a

26:04 bar is a low that unlike dudes grow almost to the bed flow

26:24 Uh, particularly great groups. In words, most of what we traditionally

26:30 the dunes and are what are described these bed phase diagrams are only a

26:36 proportion of the water dead, maybe third six. There's a lot of

26:43 on top. These unit bars can virtually to the surface. And

26:49 they scaled to the width of the , which didn't. So it's really

26:59 level of bed form hierarchy that once and shown it turns out that's a

27:09 common feature. Well you won't find on the bed face time because it's

27:16 different type of that form. So see what we can do with having

27:25 big phase diagram that you can These are the very that are measured

27:32 forms and fields that's too many. let's organize a reorganization fluid, variable

27:41 , variable water. Now, that's he went to the constant fresh water

27:52 the difference for sentiment as keep all constant by saying uh house but standard

28:05 works this water strength. No we water here and water here. We've

28:21 depth, close training range size. that's the beginning of the 5th Phase

28:29 . Pretty much the best weekend Meet side water. What's missing?

28:41 missing in this particular Could be a D. directly. What's That?

28:50 Division? No no. Just uh got to normalize the state point,

29:05 velocity is defined as in any As long as it's you know or

29:11 need record. Hi. Yeah. . You know what we need is

29:24 variable that goes into the board for turns out that's less critical. We're

29:29 talk about this moment. But this what I want you to look at

29:33 the way I want you to think it like this. In other

29:39 you ought to be able to draw like this museum. I notice there's

29:46 transition of uh phone number two The reading breaks here breaks? Don't

29:57 that. Mhm. And realize that a little different, You know this

30:08 30 years late, hasn't changed that . Pretty much settled on. And

30:14 now he added this circle loss 3rd . We still get if we start

30:22 here sand we still have no motion . Fan waves think two begins do

30:31 three details. But look what happens in phase rays? Think anti dudes

30:37 pinches up. That's a half a . So the one major distinction with

30:48 to slow death is the lack of in anything deeper than or shallow.

30:57 , so at least until we get some or rather sedimentary gravity flows,

31:06 we dealing with kind of typical We're only gonna see any dudes shallow

31:15 . Now that was based on flume . Um This is yeah based on

31:27 and um field studies. So here we've looked at we're looking at

31:36 Uh huh. Cross section. That the end of the three with.

31:46 we've got velocity increases here. The . Here's the news coming out.

31:54 sounds great with them. Yeah. we've got three different license. Now

32:03 question to you is as we look this and you look at what's happening

32:09 respect to the transitions in bed. I was to ask you. Well

32:18 I were to tell you These represent different grain sizes. Medium grain

32:25 fine grain sand, coarse grain Which of these three do you

32:31 Horse Green said why robert? What you think? Well, what would

32:51 predict? Made a sequence in sedimentary with increasing flow for coach wants?

33:14 great working. No motion seems to a little higher here and here.

33:30 . Uh huh. I'm not sure these numbers are. So let's assume

33:40 right. You see science critical Your motion motion One of the three

34:13 . Well, just tell me what sequence is for this as we go

34:18 no motion. The office old What do you what do you speak

34:23 increasing lost. You go from no to what? Yeah. Speak

34:32 Who? Yes, but what bed do you get? Yeah. So

34:42 go ripples upper place when you get stands right. What do you get

35:01 ? So you've just gotten the So which one is sports?

35:32 Which green size goes from? No , lower planner, do anything the

35:45 creates. Yeah, whatever it Yeah, that other side was it's

36:04 . Don't if you can remember this be able to reproduce it on exam

36:11 you can answer that question which is dues. Just ripples, find no

36:21 . Just unfortunately. Yeah. And important when you start looking at sedimentary

36:28 because then you're looking at brain size well as sedimentary structures formed by migrating

36:34 . Okay, now when you get field studies it gets a little more

36:39 . The only reason I mention this that there's a lot of effort and

36:45 to reconstruct the any of them. lost cities from bed forms. And

37:01 for example, you had a particular grained sand. You knew that they

37:13 then and you knew it was Well, first of all probably wouldn't

37:20 , you know, but you got narrow velocity range. So these diagrams

37:32 ways to um in for potential velocities variations in velocity. These are a

37:45 out of date now, but it's type of structure that goes into that

37:51 . I talked about last time fulcrum of determining uh sources of sediment discharge

38:00 one of the components is reconstructing the hydrology, reconstructing the velocity of the

38:09 flow and that's where a lot of . And this is just another way

38:16 looking at showing him doing hi David , the board of debt. So

38:26 about 10 m and over water It's about 27, 10% of the

38:39 down. Again, a lot of then just go back recently that transition

38:47 ripples and no ripples, ripples versus planing. That's basically that transition between

38:56 smooth and so it takes again, as long as this. If it

39:11 completely smoothed out, it would be hydraulically smooth and you wouldn't have enough

39:17 to get into it. But if any kind of turbulence little bump that

39:24 a ripple effect in the ripples If you look at the flume like

39:30 form instant once that little perturbation is into the ripples form and that is

39:36 form roughness that allows the setting to transported. You don't need it

39:43 The grange are thick enough to breach fiscal sub layer. They move as

39:50 planer bed. Now in reality this not flying a plane, It's more

39:56 a bed load sheet. This is cross section with this. So These

40:06 five m. So 30 or 40 . Made 77 depressed. Um maybe

40:30 centimeter high. Remember that stretched over mm as they move with time C

40:42 of these little bars giving you this grained sand and planer sheets. But

40:55 like this. Okay. And it even be Grap and what you won't

41:07 our rippled across tracks down here Now, the upper player is easily

41:20 . Um But in terms of the , you're about percent in the in

41:32 flume Lord Player is out of Upper planner is anything But the other

41:42 is the shape that's bad for is smoother and upper play here symmetrical.

41:56 , clean. We'll talk more about infrastructures in the second half of the

42:02 . Okay, I showed this before transition in bed forms from lower flow

42:15 to upper floor regime. Okay. if we look at upper floor

42:23 uh we see you go uh from dunes, great anti doom breaking waves

42:33 shoot for. So these are features are were first seen in the lab

42:44 that are associated with higher and higher most. And and we really haven't

42:52 any of that in those bed phase that I've shown you so far.

42:58 as we get into higher and higher , we're seeing a lot of changes

43:05 those bed forms incentive infrastructures. So to see things like this dude's except

43:21 required Again, this is a relatively this focus on upper flow regime has

43:32 been in the last decade. And so what I'm gonna ask you

43:38 do is add to that diagram. asked you to remember something like

43:49 Anti anti dunes kids and fools psychic and I'll be describing each and more

43:59 . Yeah. Let's begin to look little bit at the sediment structures.

44:06 is a little bit early, but where the notes are. Um as

44:12 food number approaches but does not exceed the upper plater exactly more similar to

44:27 wow. That's overpaid and the individual are a one. And if you

44:41 at it and process flat so so do we have perfectly spiritual grains range

44:52 are elongated in some ways. So this shows is the fact that these

44:58 parallel as you increase the increase the in play there. They're still oriented

45:16 . We have the individual braids dipping street. Mhm. So we begin

45:25 see that transition within flatbeds upper We see a transition until finally we're

45:33 into antidotes. Now the antidotes remember there kind of like hydraulic jumps are

45:44 really hydraulic jumps, but what happens perversion recent and breaking ways showed the

46:01 of the settings and migrating upstream. can see that you can see the

46:11 and the resulting bed forms. Or me rephrase that you see the surface

46:17 of the antidotes in the water. in phase with the bottom and this

46:22 what they look like. So, we likely to see them beaches?

46:30 all seen anti dunes having been formed the beach. And that's one of

46:35 two main places that you're likely to able to see it in the

46:43 Now they can go from standing waves breaking waves. You see here,

46:53 the waves are beginning to break and are breaking upstream. So this is

47:02 the waves are breaking upstream. And you're you're getting such large bed forms

47:15 you are getting true hydraulic jumps is clear, you're getting larger troughs and

47:26 upstream dipping packets. Okay, so would be the kind of thin Hackett

47:40 this is an increasingly large package. finally we get a very large upstream

47:54 um out of phase bus migrating Yeah. So that's what we're seeing

48:03 in this flu. Now they can so large that these cyclic steps and

48:18 . Wait, it's politics. baby. A couple of meters up

48:35 . We need huge pages here. these are being formed in deep water

48:50 submarine fails and these are the factors migrating up the seats more. You

49:07 to do something. Okay, Um, how we doing on

49:22 What time is it now? It's . What? Oh 10.

49:31 Um, let's stop this. Recording it is. Okay. Um,

49:45 see what we can do that's preserved the rock record to be able to

49:50 those bed forms is the first Just again, a little bit of

49:54 . Um we talk about stratified We talk about dad's eliminations. We

50:02 to use cross bedding and cross stratified cross laminated the same. Uh that's

50:11 incorrect if you want to be Stay across strategy. But that is

50:19 thicker than a centimeter and a lamination less than a centimeter. So strictly

50:25 , cross bedding for thicker, thicker . Cross laminated thin strategy. And

50:33 individual strata can be defined by a of different things. Bedding planes,

50:40 orientation. Remember we talked about implicated , sand. So up here,

50:52 here appear we've got upstream dipping implicated here, flat sand. So that

51:03 be that transition. I showed in upper planer zone from the lower velocity

51:10 planter to the higher velocity variations in sand. We're going to see that

51:14 lot when we look at lamination. all of these are ways in which

51:21 lamb in a uh or the Better sand can be defined.

51:26 we've got agreed upon criteria for how describe it. I don't expect you

51:33 remember anything other than this except to that if you were in the business

51:40 describing layers, there is a a between uh thin bedded and very thick

51:50 and thick bedded etcetera. That actually enough. So you may use it

51:57 in conversation but in reports and publications it has a family. Okay,

52:05 the lamination, we better set lamination best or I should say strap are

52:12 formed from a variety of processes grain deposition from suspension grain flow deposition from

52:23 down the slip face, translation deposited a migrating rip. It says when

52:32 should be just it could be water wind. Okay. And then what's

52:38 attraction carpet. And this is a zone that is a type of brain

52:51 where it's, there's a disperse it . Talk about a little more later

52:56 um on a plane or surface that a upward Corsini later became So I'm

53:07 use wind as an example only because easier to take a picture of these

53:13 in Sandon and a dude. But we got the zone up in here

53:20 sediment is deposited from suspension on the face. It's over steeping and fails

53:28 . So here we have the collapse the grain flow. And then up

53:37 here we've got migrating ripples that are to give us our translating strap.

53:44 just for fun we've got price fossil well or what will become a trace

53:51 . Now, one of the reasons interested in these seemingly academic distinctions is

53:58 are huge differences in the porosity and . Especially permeability of these different types

54:08 strategy. If you look at grain , You have much higher permeability average

54:17 eight Darcy's in this particular field study translating strata. Two diversities and inter

54:25 forget. Okay, so we're gonna that as we begin to parse the

54:35 say cross stratification into different types of and the different layers within different bed

54:42 , migrating bed forms, it has differences in the flow conditions of our

54:49 rock. Now the other thing we're do is we're gonna think about how

54:54 package these various straps. For we can talk about a four set

55:02 is pretty straightforward saying where we've got dipping strata typically confined by less dipping

55:13 . And then we can talk about set which is a genetically related group

55:22 layers and then we can talk about Cosette which is a group of a

55:28 . It's a package of sense. let's start with the fourth set that's

55:35 of the easiest thing to visualize and basically it's going to be associated mainly

55:43 transverse bet forms migrating down street. , ripples and dips Okay, now

55:52 that zonal flow separation occurs right about . Uh that occurs anytime there's greater

56:00 about 12° depth. And as if a much lower, more subtle

56:08 we don't create that zone of but once it builds up to

56:15 then we begin to have this zone we could actually develop not only a

56:22 flow, but maybe even upstream migrating at the base. So here we've

56:31 this then then because it's big that depositing down a slip face. So

56:43 basically the result of that downstream Now, if we look at the

56:50 of that, particularly that basic it can be angular and gentle or

57:02 . And what that represents is the from moving mainly as bed load to

57:10 amounts of suspended. So what suspended does is tends to stop and and

57:25 the bottom of their slip face. is just due to avalanches drain flow

57:33 , we've got the deposition of sediment suspension and actually in this particular

57:40 we can actually have upstream ripples as . So we're already seeing how that

57:47 shape of the cross strap, particularly the base. Tell us something about

57:53 relative strength of flow and the type sediment deposition mechanism. So we here

58:03 got that grain flow coming down on left and that tangential modification by deposition

58:14 sediment in that eddy zone. And in some cases reverse ripples.

58:23 if we look at that grain flow in here, what we see is

58:38 a downstream increasing grain sauce and we see it's inversely great. The inverse

58:47 is is the result of that traction disperses pressure that forces the bigger grains

58:54 the grain grain contact towards the Its inverse rating in addition as its

59:02 ng down the slip face if you've been on a sand dune and noticed

59:07 an avalanche forms the coarser grains. the finer grains, hire women.

59:15 so as a result, you go finer grain strata at the top of

59:21 grain flow to of course your grain at the bottom and it's inversely great

59:28 from rainfall is just the opposite. other words, once that get out

59:35 money suspension, what's gonna because it first courses stuff what's transported farther the

59:45 . So it's going to find down or down slow and it tends to

59:53 or anyone spot The course is settling the five. So that's gonna be

59:59 . So there's a significant difference between grain size patterns of rainfall versus grain

60:13 . So let's just take a test here's the basal contact and particularly right

60:22 in here. Okay, because this coming down to about here, would

60:31 call that basal contact, angular tangential com K. Baby? What do

60:41 think? Uh huh not concave? , so that leaves us two

60:47 Uh Robbie is down to you. have 5050 chance I think so

60:57 To me it looks angry. Um So yeah, I mean when

61:10 look at this contact it's pretty steep the way down. Okay, it's

61:19 much like this. There's not even hint. Well this is the only

61:28 where it looks slightly tangential and that's a slightly different phase of pro

61:36 Okay, now the the other thing like you to know besides the angular

61:43 is the top is the top cut like this. I I don't see

61:55 . It looks like it's gradation all plane to slip face plane. And

62:06 is kind of a breaking slope right here. And that's actually the brink

62:14 . Remember I said that sometimes you've a great point and it's something one

62:23 . So you can actually get what like a top set if you got

62:30 entire doom preserved. Now, the that's rare is because usually the top

62:37 the dune is truncated by the next or next Bedford. But here we

62:45 see the entire dune preserve. now over here we don't the top

62:57 this spin is truncated by another dune top of it and it's truncating a

63:04 below it. Okay, so the now is as before, is it

63:11 tangential or concave? Robin? Okay, what do you think?

63:24 agree that again? This this unit ? Yeah, I I agree agree

63:50 with you painting because this part looks straight, it only begins to curve

63:56 around in here and then it becomes ginger. Okay, so I I

64:05 suggest that unlike the previous one which formed strictly by avalanche, this probably

64:13 more suspended. Okay. Uh No. You know the other thing

64:29 in here, it actually flattens out the point where it's almost the

64:36 And if we got upset 4th not much of um the bottom of

64:49 transverse platform, particularly if they have lot of suspended sediment. And if

64:54 any reversals that becomes really important. of all, it's it's square.

65:00 might see preserved those backflow ripples is to be on the bottom, said

65:07 here's just an example and you can these ripples trying to go up the

65:20 of the flow was giving you more a tangential flow a tangential look.

65:26 it says that the host set is very distinct from the four set.

65:34 . In fact, again, there see that upset four set bottom

65:41 Uh Now a couple of things about bottom sets, they actually have the

65:45 preservation potential and the top says the preservation potential. Yeah. Uh

65:54 And so they are more important in sense not more important but their importance

66:02 magnified to the point where sometimes that's you get depending on how much erosion

66:10 occurring during that deposition. Okay, preservation pretty rare. That would be

66:17 example of what we saw the So we didn't really have courses because

66:23 was um, Lord lost a this is the second example. We

66:30 didn't have the top six. We down here. I don't have an

66:35 of it. But you can imagine it uh, you've lost all the

66:41 . So again, here's the full talked about now, one of the

66:47 that's important is that not only are bottom sets different uh morphology, if

67:01 rippled, they tend to be different size and different ferocity. Especially as

67:10 get more and more rainfall or suspended . Rather they're gonna be fine or

67:17 . And so what those zones do they represent flow barriers. So you're

67:24 to look at a series of low associated with these basal programming dudes.

67:34 , this is most obvious in the deposits, but it can also occur

67:40 uh uh area some as well. keep in mind that as we see

67:55 accreting zone of dune deposition, we packages of higher and lower porosity and

68:06 . Yeah. Phone by presidential potential grain local flow barriers for variable.

68:17 can affect both vertical and lateral from building, usually unsteady flow that.

68:26 let's look at the forceps now and about what's going on within the forceps

68:31 terms of avalanche versus rainfall, the creatures. Or if we look at

68:48 in a horizontal cut, you see the brain, Whoa, Evel.

68:59 they are working hip section. So just have a look at that saying

69:09 imagine what a cross section might look going from. So the head of

69:15 flow, it's going to flow and flow. So if I did a

69:26 is gonna be the grain fall and , there's going to be a truncated

69:44 . A double scarf up in B. It's gonna be low

69:56 So we've got a logo at the and then going down flow. We've

70:11 this down flow low and if I it horizontally, you see this,

70:24 scarves up here. Okay. And if we looked at the rating,

70:33 going to be course towards the And if we looked at or down

70:40 grading, find the course and then the grade, most of it's gonna

70:48 inversely grade. Now, another feature the four sets are local provocations.

70:58 are called reactivation services. So we the flow coming in truncated and in

71:11 and that we see here with the here, I forgot that that was

71:16 same thing. Here's another one. gradation truncation, Pro gradation location.

71:31 , So those are the reactivation Okay, Now, those The four

71:43 consist mainly a great falling, great . They can be locally truncated by

71:49 services and they can be either cross or cross laminated. Any how thick

71:57 individual lamination czar. They can grade into bottom sets and upward into top

72:09 . Now what I wanna do next to begin to subdivide larger packages of

72:19 structures into sets and co sets. let's look at this package of sediment

72:31 . Okay, here is a set to here. Here's another one and

72:41 one. Okay, here's one That's basically what they've been looking at

72:47 a set and a set is basically assemblage of strata deposited by migrating

72:56 One rip one did. Yeah. set here is similar to this set

73:07 this set. In other words there multiple dunes migrating one on top of

73:18 . But they're genetically related, they during the same event and then all

73:24 a sudden we get some change so genetically related package of sets is over

73:38 by something different. So we're gonna those lower sets a Cosette and now

73:46 gonna call all of these sets a Cosette. Now in cross section.

73:55 . In you these says don't look different. But why do you suppose

74:04 decided that this said is different from set and therefore should be in a

74:13 Cosette. What do you see that's . Um Is that cross bedded down

74:39 . Not here. Okay, close this actually is a type of and

74:47 is what we go through. This more I mentioned it perform which probably

74:57 , this is what you get a D. Transfer. This is what

75:07 get. Yes these could be any scale. This could be yes.

75:16 let us assume they were. Do think therefore this is going from high

75:24 velocity, low velocity high up Thanks. Okay continue to exactly.

75:42 back to that diagram. Everyone the a deposition of wayne in florida.

75:57 . Uh now we can also look the idea of sets and cassettes into

76:04 nature of boundaries. So The first down this here that rates two

76:14 In other words it's street migration. in the second order that are a

76:28 service step rates concepts. In other this type of, that's the second

76:41 balance and a third order it basically together genetically related cassettes. So think

76:54 it as a flood deposits a group sediments deposited during a single event.

77:01 going back to this um this would a second order bounding surface. Whereas

77:12 over here would be a first order surface and we don't see in this

77:18 the whole event grouping but we'll see elsewhere. Now. In fact as

77:29 go from little that's the big first order, 2nd, 3rd order

77:45 3rd and 4th uh finding event. order is the basic champ is basically

78:00 end. Thanks. So, going to here, we set first order

78:10 . So I showed you this, a lot of information you could clean

78:15 this folk. We're without the annotation . Um I'm gonna skip this except

78:28 say as we get into increasingly complex beds, mid sets. Um We're

78:40 going to be constructing large candles. programming strong faces. Everything I've said

78:52 respect to sets to this point is to uni directional flow, mainly in

78:59 . We're gonna see that concept can over into the only deposits marine

79:11 Deep Sea 7, 7. And is how that first order set

79:19 Five trans relation of these programming But look at the top versus the

79:31 . Uh We're actually changing something is go from top to bottom. And

79:39 is the rate of deposition. So the top one we're actually going to

79:53 isolated ripples packages. These are sometimes star ripples. There's just not enough

80:01 for them to climb on top of other. But as we increase the

80:05 of sediment deposition of sediment supplying The ripples begin to a grade

80:13 And so that's what we call climbing . Okay. Each of which in

80:18 particular case, all these ripples, could be doomed. But here they're

80:24 all these sets are related to the type of bed form. So they're

80:31 part of the same Cosette. And on how much erosion occurs on the

80:37 side, the maximum set thickness can no greater than the height of the

80:43 form. So when we go back this, we know that could not

80:53 any tires any other. Now there a hint, but I didn't absolutely

81:06 suspect this higher. And they want know the height of the bed floor

81:16 , among other things, that's going give us information about the strength of

81:20 in the water depth. Now, we look at climbing climbing, we

81:35 see a variation by only the four we had to get to see so

81:51 a priest, the backside. finally they just literally rolled straight up

81:58 we see variations of that thing Where And I don't you don't have

82:05 know rather remember these phrases. What do need to know is that that

82:15 is increasing amount, relative amount of set. Okay, And so you

82:21 see here, uh you still see backsides. So this is the angle

82:31 climb. That angle of climb is to go almost vertically. So,

82:39 actually seeing an increase in the amount deposition suspended sediment while these ripples were

82:47 . And that's typical of flood events rivers. So, here's that angle

82:55 plan, going from literally the dark , two ripples with the backside

83:11 This is worse, increased amount of deposition. Now, this is what

83:23 were describing looking. But the problem sometimes It's hard to see the four

83:36 , especially if they're just saying the are thin. So sometimes what we

83:43 see and the lamination are really we just can't see the forces.

83:55 so that's what we call translate Sometimes they're called sued elimination because they're

84:03 actually a boundary searches and taking on like these. Now with rivers,

84:17 if there hasn't been a lot of . Even growth, you pretty much

84:23 see four cents where you can almost play where you rarely see process or

84:35 so one of the distinctions will Look at the only deposits is the

84:41 of the translating scrapple from truncated ripples almost invisible. So again, here

84:59 see the fine and we see that really quite strong, almost vertical.

85:11 down here you actually see truncated back sets to preserved. So sad and

85:25 almost vertically. Accreting everything here is deposition during increased volume. A rate

85:36 suspended self. Okay, now I this earlier, but I didn't focus

85:42 as much as I should have when look at two D dunes or

85:51 If we have a true dip section right angles to the strike of the

86:01 , The first order bounding surfaces separating will be sub parallel. In

86:09 ideally if it's a perfectly linear they will be parallel. Okay,

86:21 if the strike section is truly parallel the crest, you're gonna have apparent

86:32 that are horizontal or very low angle . There still be sets boundaries.

86:39 order bounding surface system, but there'll low angle because you never have a

86:47 plainer linear feature and you never have exposure exactly parallel to the rest.

86:56 we get into three D dunes, a scour pit. The dips are

87:01 multiple directions. And so the sets the dip section, you'll see some

87:10 Phil and in the strike section you'll a scallop. Their results in this

87:19 of the scallop pool. So this that trough cross stratified sand? There's

87:26 cross stratified sedimentary structure to talk Yeah, now we're gonna call these

87:35 across strata and trough cross strap. also see in the literature uh plainer

87:45 strap. I find that confusing with betting it's a lot preferred tabular but

87:55 hear about it. So we could a habit or cross stratified sand by

88:04 or about dudes. Okay, so look at some ripples. This is

88:11 actually let me just ask you, this saying strike section or a dip

88:18 , dip sections being in the direction flow? Yeah. Is what dip

88:29 flows here. We've got the four exposed here are the sets. I'd

88:37 the first order bounding services which are sense and you can, I think

88:45 can convince yourself here, this is four sets a lot of suspended

88:53 Okay here again, we've got sets of the things to notice and and

89:03 hard for me to draw being left . No, that the bottom part

89:12 that set of ripples is Lighter than four set. So there's actually a

89:21 set formed by this river. The stuff probably is um organic material.

89:30 up here, look at what we , we see a ripple that is

89:40 that those ripples that were forming the Travis. So we actually see the

89:46 form here that formed across the out here. And the reason we see

89:54 is because its mantle with mud. that real dark stuff on the

89:59 that's mine. So we've got first bounding surfaces all along here. Then

90:05 have a mud drape Which if we draw the base of it would be

90:10 second order bounding surface. And then the top of the mud rate,

90:15 third order bounding surplus. Why? ? Because the mud drape basically says

90:21 event is over that flood event that depositing all of this stuff and whatever

90:28 can't see at the bottom ended with deposition of the Hence three Dimensions.

90:38 , three dimensional bounding surface. here is a strike section and here's

90:45 very clear that we're looking at Now they're small troughs because they're small

90:56 . But if we took a picture horse green dooms that would actually look

91:04 just bigger deal. So that's what looking at now the two D dunes

91:11 tablet across strata. The three Dunes 12 across strata. And just

91:16 kind of visually this is what it like when it zoomed is bent.

91:23 is the trough that was filled with dipping set and if you truncate

91:36 those troughs are cutting into other And so I guess what's called rib

91:48 , which is what is going on and you can even get that in

91:56 . Okay, so let's have another , so to speak. Let's look

92:02 this particular exposure and it's certainly cross deposits. It's sand. It's variable

92:17 it's coarse sand. So we can with that when when I kind of

92:25 a in the outcrop. My first is to define the bounding services.

92:34 I've got bounding surfaces here here here . Little fuzzy here, but there's

92:41 here here, this one here looks this here. So I'm gonna start

92:53 defining them both where they occur in G. On the trip.

93:12 And there's in geometry. I'm thinking the cross sectional shape everybody and the

93:26 . So let's start with thickness. Robbie, how would you describe the

93:33 in thickness of the sets? Going bottom to top. It's it.

93:43 , they're thickening. Okay. Um Okay so Hayden, how would

93:50 describe the shape of the sets as go from bottom to top.

94:06 okay, again, I don't like laminar. But uh there is a

94:12 a term first of all uh as this is a dip section, flow

94:19 left to rot. Let's go describe the lower stance or set boundaries different

94:29 said this one. There's another one in here. Lower angle.

94:39 Lower angle. Think about it in of this. Are they more like

94:48 or travel across strata in dip Yeah. Yeah. Uh And the

94:57 with tabular, Is there pretty much Jack over some distance? And so

95:07 what do we say at top? , the top Which is called

95:19 12. Okay. Okay. So got several observations that we can

95:29 We have sets that are on the of a few millimeters to Yes,

95:39 mean thickening upward. All things equal higher bed forms. These are

95:52 How do I know they're dunes? if no one at some point they're

95:56 high to be ripples secondly, have told you. Of course Grant

96:00 Okay, so we got dunes that getting all things equal. Again larger

96:09 larger as we grow up the Now there's no obvious truncation to suggest

96:18 are different flow events. So this probably one major flow event. The

96:27 here. This is again down in . This is a first order bounding

96:40 . What's going on here. What you say is going on at that

96:46 surface? Is there a transition that can see, you may want to

96:58 it here. So yeah, that's second order bounding surface. And

97:10 Oops. Okay, why did you it a second order down the

97:21 Because it's going from tabular to trough strata and therefore from two dimensional to

97:29 dimension. Dudes. Okay, now third order is blow us in on

97:35 of this. We don't know, it's pretty thick positive for an

97:39 Okay, down with uh this transition tabular to trough, would you say

97:49 increasing or decreasing velocity as we go straight up section, We're increasing.

97:57 , we're going D-3 d. And also increasing the height of the bed

98:03 . All of this is occurring during flood a river. So I suggest

98:10 this is actually the rising limb of flood hydrographic as the water is getting

98:19 and the velocity is getting higher, dunes are getting two dimensional dunes are

98:26 higher until they grade into three dimensional . I didn't hire yet. That's

98:31 lot of information that you can do reconstruct the flow conditions of these bed

98:39 . Okay, again, ripples are ripples. Okay, that is a

98:50 army knife uh about this much call six centimeters, maybe 10 centimeters.

98:59 is this uh form by ripple, ? It's too big. So this

99:07 to be do uh but let's play game? Oh and also it's the

99:14 direction left to right. It's clearly oriented. But let's play that game

99:20 uh defining the bounding services. Okay if we got dunes at the bottom

99:47 do you think we have up here here? Yeah so we go from

99:58 to rips. We go from thick to decreasing set thickness within the

100:09 So that suggests maybe water depth is and maybe velocity is decreasing. Not

100:17 sure yet. But uh second thing looking at is by the way there's

100:22 bounding surface down here and there's a of a zone here that I would

100:27 as a bottom set. Now if look at these bottoms here there's some

100:35 of suspension but basically a lot of is pretty straight and then we get

100:42 ripple cross laminate. Mhm. So lower part tabular cross stratified dues.

100:53 the upper part though. And maybe can see a little more clearly now

101:00 got ripples. And You think those are two D. or three

101:11 Three D. Because they're pinching out in deep section. And then finally

101:19 got thick mud rate. So again order. Second order. First

101:29 And down here I suspect that's another order because I think this is pretty

101:36 one flood packet. Yeah. Now you had a core uh you could

101:49 tell a similar story. The only you wouldn't be able to tell for

101:54 is whether or not. And and had never really quite said it or

102:01 tabular or not based on this. are pretty parallel sets are pretty constant

102:08 . So I would say tabular. . The fact that this is kind

102:13 horizontal, this is what makes you it may be tap water, but

102:18 sure you know what to do. , and these are four cents.

102:23 still have a first and now, know here That these are ripples and

102:30 even in core you can see there three D ripples. So this is

102:36 order and then this mud is gonna a third order downing surface. So

102:42 can make a lot of these distinctions poor. Now one of the games

102:51 play is trying to reconstruct flow depth set thickness of dunes, We know

103:00 dunes are at least seven cm We know that they usually scale to

103:08 measure of flow depth. one of problems is we rarely get a complete

103:16 of the doom. There's always almost always some truncation. So we

103:23 , alright, the the height mean of the dunes of the the sense

103:31 is typically rather of the dune height typically some fraction of the septic,

103:39 sorry, the set thickness is some of the dune height 2 - three

103:47 as high. And so if we that we can maybe try to predict

103:54 hide and from that, so So here we've got two m uh

104:07 Um almost three, let's say, call it two m in height is

104:12 complete heights because uh we haven't seen truncated. So that suggests that the

104:18 on top was on the order of m above the point bar at this

104:29 , which again actually is pretty pretty for this. Uh The problem is

104:36 been a lot of work more recently dune hide versus flood depth and there's

104:43 lot of variability and so lot of within scatter and variability as we get

104:54 higher and higher flood depths. So range of uncertainty is pretty high.

105:02 so don't you will see people trying reconstruct flow depth. Sometimes it's a

105:11 it's the only thing you got but the very potential errors in those

105:20 And then God forbid you're trying to flow depth to predict Haley of

105:27 hydrology and sediment transport and add on . Oh, yeah. And I

105:33 to estimate channel slope. It results a very wide range of estimates.

105:45 I said, trough cross stratification, shape is the same. The only

105:52 is scale and dunes. Well, are really big dudes in very coarse

105:59 gravel, except here, these are . See this big chunk here

106:09 we're looking at amalgamated channels and you can't tell where the base of one

106:16 is. These are at least this here is probably 1/5 order bounding

106:21 The base of the channel. So we get channels depositing on top of

106:27 other, the lower part of the field typically is the one highest

106:33 So we may well have 1st, , 3rd, 4th and 5th quarter

106:41 surfaces in that amalgamated channel field. , so that's kind of what we're

106:46 at here. I'm not gonna bother this, but this clearly is is

106:52 dune. We talked about that. here we have the trough cross strata

106:59 more sandy dudes as opposed to more debts. And here, one of

107:08 favorites here, we actually have that point preserved the crest. And then

107:15 have all sorts of ripple uh cross . We've got the two D.

107:24 overlaying by three D. Ripples. , we could go through the same

107:29 saying what we could do with a on. That's what um According to

107:44 , the height of the dunes scales flow depth. I've already said.

107:50 iffy. Uh But here are the in dune height and spacing in what

107:57 call again, the very large are gonna be unit bars and probably do

108:05 and do not scale with water And so this type of stuff in

108:14 was before our recognition that these larger are really different types of bed

108:22 Okay. Uh And here we have Dunes here and three d. Dunes

108:34 their superimposed by the larger features excellent this. Oh, there's some little

108:45 dudes down here, you can't really well uh which are unit bars.

108:51 , so we've got unit bars, on the unit bar um the flow

108:58 oops, The flow direction is kind coming like this. We can tell

109:03 flow direction by looking at the the of the dude's unit bars are often

109:12 an angle to flow direction. So you're looking for evidence of flow

109:18 stick to the dudes, not the bars and also not the ripples because

109:23 ripples are too easily modified by float . Okay, so down here,

109:34 most likely is a unit bar with dunes on top. Okay. And

109:45 probably is something like this where we a point bar. We've got these

109:50 bars with the dunes down here and they as an aggregate form a point

109:59 or sometimes called the compound can. when we look at the sediment deposited

110:10 that point bar, we're gonna see and dunes and unit bars in flood

110:19 , defined by migrating flood packets. what we're gonna anticipate when we look

110:25 river deposits. Now, this particular deposit, these are this is a

110:32 note, the fine grain, this the trinity. This is the

110:36 santa's little coarser grained. And these are are gonna be unit bars.

110:46 , With little dunes in between. gonna dig a trench right here and

110:55 is the unit bar crest. This Roxana Herrero masters student and this is

111:04 deposit of that migrating unit bar. . And so it's about a meter

111:17 . And as we go back it's something like 100 m wavelength between that

111:26 the next unit bar. Now unit have been described a lot on graded

111:35 and that's in part because they're easily access. So here is a unit

111:41 that's been pro grading, it's about meter thick, Not unlike what we

111:46 actually a little lower that, but notice there are reactivation services and we

111:55 see that unit bar broken up into . And that's because unit bars will

112:05 pro grade so far during a single . And then there may be mud

112:11 , there may be modification. the bar pressed and then it's reactivated

112:18 the next event. So what happens what appears to be a very laterally

112:25 cross stratified set is really broken up reactivation services, which could be mud

112:31 and therefore affects the lateral permeability. vertical permeability is a lot more variable

112:40 the bottom and top are often separated finer grained material. Uh Here we

112:49 what are probably unit bars in the river with dunes on top of So

112:59 scales, uh 100 50 m here here, 10 m high, we

113:08 get some pretty big uh features in . Yes. Now everything I've said

113:18 this point is uh related to lower regime, transverse bed forms increasingly,

113:28 seeing evidence of upper flow regime bed uh like anti dunes chutes and pools

113:38 cyclic steps. Now the transition from to plain bed to anti dunes is

113:48 what are called humpback dunes. And basically dunes that are beginning to be

113:55 . And so their gradation all. at some point you begin to get

114:01 this, there's no angle described So finally we get nothing but minor

114:16 . And and so let's look at upper player bed reading a ripple.

114:26 look at that transition where we've gone dunes to humpback dunes to planer

114:35 Okay, well, the planter they're usually in birthday graded because its

114:43 carpet. And one of their characteristics that there is a parting linea ation

114:55 at at the bedding surface and that reflecting that parallel linea ation of the

115:05 grains I showed earlier. So when break these parts, you see this

115:10 life. Okay, So parting radiations characteristic of upper floozy place, your

115:19 . Yeah. Uh And then that's dip section usually adversely graded. And

115:26 again a picture of parting linea ations . Now here we've got our in

115:38 beds upper floor regime less than a high wavelengths pretty long. Desa

115:49 Okay. Hello conditions uh pretty high of phase And individual grains parallel to

116:04 flow. And at least in the part of the upward cleaner beds.

116:10 have these low angle bed forms or depositing flat rains increased velocity.

116:23 lose those bed forms and we get implications in cross section. The individual

116:33 are moving as a carpet, the are interacting, there's a zone collision

116:46 graze in the Salvation. In that of collection results in the capture grains

116:54 migrated up to the that was not pressure. They can't move laterally,

117:05 start down. They have to. in verse three. Now, let's

117:20 as we go from that planter bed the antidotes. And again, you'll

117:25 it mainly on beaches. You do cross section here, you see that

117:31 beds are dipping like this, but flow of the water actually is like

117:42 . So the bed form is migrating and I have not seeing these real

117:52 . But here is an antidote dipping float and and those when you start

118:05 at it more carefully. There are low angle truncation and kind of little

118:15 . So planer too. And he not unusual assemblage easily overlooked. I've

118:24 them more times than I want to . Now a second place where you're

118:30 to see him in the field is a sand flat and were braided stream

118:36 you got ripples that are being cleaned . And this is an example of

118:41 type of anti do cross stratification that will get in the great sand dunes

118:46 the river. And this is a of some of the sand deposits from

118:56 Medina River at low flow. And can see how the upstream Migrating bed

119:04 giving upstream migrating or upstream dipping four okay. Um This is just a

119:13 30 showing the breaking way, throwing upstream migration afloat. And these are

119:23 some examples of what it would look without going into details. But this

119:30 what the cross section in. Thank Michael. It's almost like it's trough

119:38 stratified, but these aren't angled. other way of distinguishing it from 12

119:44 stratification. Look at the dip century playing so this, you can honestly

119:53 be tabular unless you saw it over . In case of this might be

120:00 story here. Clearly not okay in again, but oh, in this

120:17 exclude in the case of the river , you basically go once you determine

120:34 this is an anti, you know it's now in some cases you have

120:42 program information like this may break down to, but at the beginning of

120:56 you either have to know that this an upstream or you have to have

121:09 associating uh flow indicator. That's good you. Right again, just more

121:21 the same. Um I include this because this is a peel that was

121:29 from hurricane harvey deposits on the on the buffalo bile and one of

121:37 students was doing their masters on And this is the first time I

121:42 recognized upper floor regime. Anti dunes a flu viel deposit that wasn't a

121:52 flat. This was just a good point bar. But the appeal brought

121:59 the variations in permeability, which is in brain size and emphasize these low

122:08 plantations and dip to our right to flow, left and right. That's

122:17 I'm saying. They're probably, they're more common. And I realized,

122:23 think most people realize He's just six . Uh, and again, more

122:33 notice here we're beginning to get prior dippy upstream, but we're going to

122:42 bigger scout as flow velocity increases. begin to go any due to choose

122:52 . Uh, this is one of friends working on alluvial deposits. These

122:57 playing beds are pretty thick. That a little surprising. But then we

123:02 into this and this was actually the time in the field. See

123:11 Uh, and if the student has to, if you're dipping up

123:17 the clothes, right. This is large, y'all want to build and

123:27 we're looking at is something more like . We're going beyond the interview,

123:36 into chips and pools. Yeah. . So this is if you

123:47 uh, as different people define There's more of the same escaping.

124:03 , and here we have unstable No anti dams the suggestion here is

124:21 they can migrate their stable, they're saying you'll never see this almost always

124:29 to be unstable and they will give these wasn't shaped packets of sex dipping

124:38 strength, the cool larger sour uh . Uh so regular doom anti that's

125:06 sequence we see. And this is of what you're looking any news coming

125:16 that uh, and I'm not gonna into this more except this is just

125:26 to show how you can use the of set boundaries and bounding surfaces to

125:34 um different types of upper flow regime in this feature here. This is

125:43 sea floor and these are migrating literally measure erosion deposition by repeated metric

125:56 Look at these seven waves that are flow regime and look at what they

126:02 like. Uh, and here is a cyclic step interpreter. So we

126:11 these upper flow regime type structures even on submarine fans, in certain places

126:22 fans, not everyone, but particularly we're going from and find axial flow

126:32 a jet flow is beginning spread out the fan from the channel to the

126:38 . We tend to get these and what I show here. That is

126:46 large scale horse brains ships and foods accepts this case. Okay, so

126:58 me end by reiterating that we can different packages based on they bounding

127:15 So yeah, 1st and 2nd order , we could start at the other

127:23 and say we've got a very large meander built the big Neanderthal. It's

127:32 600 individual channels. Our 5th order services within the channel we have flood

127:47 of metal bars that are free. the fifth order bottom there is increasing

128:00 downstream creating that will be each of . Also is 1/4 order. That

128:14 order package bounds either single or multiple and talk more about this. The

128:28 absence of these is the unit bar gonna determine whether not blood Package will

128:39 bound by 3rd or 4th. And then within that we've got the

128:48 order package please. Uh 1st and I don't like I'm like recessed Because

128:58 really wanted to see 1, 3. So we got, when

129:06 started down services, cassettes, packages concepts feature basically process go back

129:17 Now this to end. Uh let say when you're measuring a section of

129:26 a lot of logging up from the sometimes use a shorthand or what we're

129:35 at capital S capital he B four . But I'm gonna call it problem

129:54 we don't distinguish between two and sure four. Oclock its really low

130:11 cross strap broad channel scours the massive could be because understand or or typically

130:28 we lost and we can do the thing gravel. Is it Matrix

130:35 Class supported. Will actually use this we talk about and this is just

130:44 for general, a little different but beginning to get closer to a,

130:54 kind of common shorthand about describing, , core in sections with uh,

131:03 shorthand gets complicated. You don't need read this but just recognize there is

131:08 least a template that's available or dealing measure sections. Okay, so that's

131:19 for this morning. We can check , uh, recording down and it's

131:27 for lunch. So it's 11:30. about 12:30 to come back?

131:40 Thank

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