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00:02 Oh, estuaries will not be on exam. It'll be on the following

00:08 . Uh I'm gonna get as far barrier islands as I can and I'm

00:12 wrap up a little bit of it . Uh but it won't be much

00:18 you to be responsible for when we at coastal systems. We uh sometimes

00:29 divided not only based on tidal power way power, but also transgressive versus

00:39 in some tidal flat. Think of strand plain think it's regressive, they

00:47 regressive, but barry Rollins are put the transgressive that and that's actually not

01:00 case. Uh Having said that uh gonna there's only been minimal programmed ation

01:07 barrier olives within the time they've been the last high speak. So even

01:13 we call them for whether they're putting transgressive species well, we'll see that

01:21 can in fact and doing that. . Ah Of course there are some

01:28 between that and say strange plane, what's behind it. That's part of

01:34 . But we're still looking at a grading wave dominated shoreline and we talked

01:40 how ah you have brought gradation, can have vertical aggregation or you can

01:48 elements of transgression. So we're gonna at transgressive islands as well as programming

01:54 . Now, one of the big big differences between us as transplanting and

02:02 one is the anybody water behind and the title endless that connect that they

02:13 with the open ocean and the related and flood tides, deltas. Uh

02:20 we're gonna see that as we look this transition from wave dominated to mixed

02:26 , we see the geometry of the Rollins is changing as are the associated

02:35 , sedimentary structures we've talked about Uh, so here are two very

02:41 of in members, uh, here of a higher title range time.

02:51 looking at the texas coast versus uh, west coast, uh,

02:59 coast and Carolina's. Uh, and look at four examples. Yeah.

03:06 micro title kiowa, a little more and rain will fall a little more

03:13 range. And then you'll see even little more time. But all barrier

03:19 . Let's, first of all, at the micro title setting texas

03:23 Let's look at you see all of roads and uh, we've got,

03:34 uh, it was in the East , west bay sitting there and we've

03:41 some tidal inlets as well. We're to focus on the program creation portion

03:48 and the shell family basically from a of pores and pits were able to

03:58 this program. Radiation beach ridges From here and dated about 3500. Sounds

04:08 likely 5000, but indicates just a 1000 years to the present. So

04:15 is a appropriation of very violent. see some truncation in here.

04:21 these are related to periods of erosion aggression and appropriation. So even in

04:29 period of time, it hasn't been appropriation that's shown, especially with this

04:36 . Him. Now, as we at that, we can think of

04:44 as kind of shoestring sands where we these barrier realities and we can recognize

04:50 in the core and in uh uh have weathered sand and then laminated the

05:01 sand. Um and it's generally of not from innovated sand and blood to

05:11 sand, but borrowed two laminated So you should already see the relationship

05:18 the vertical sequence of the strand plain and the programming beach deposits in this

05:26 . So here's an ice pack that prints and about 30 ft um bit

05:34 based on the same, we're going pitch it. Now, if you

05:42 to look at more here, you basically a programming shortcuts we've described.

05:48 been there in the back flat, gotta watch off the they are basically

05:56 course of and then they have to . That. Had to do with

06:05 the barrier flat ceased getting sediment washing the island, it's still getting settled

06:15 with the island, but where the is wide wash over doesn't occur.

06:23 then we get in the film, England is 5th and there's a short

06:33 pace. It's a finally upward just like channels all day. But

06:39 there's this coarse grained cap, the or the beach deposits that are coming

06:45 on. So we'll look at those more detail later. But the point

06:53 is that we've got three very different sequences within the sandbox within the sand

07:00 pack. Now, when we look Kyle Island, um, we also

07:09 pro grading beach ridges. Oops. , we also see this kind of

07:22 truncation. Um, and, and in fact, it's something I think

07:29 see worldwide. I thought up on Yukon delta, uh, down

07:35 Uh, we're looking at some variations sea level and therefore transgressions and regressions

07:43 what we call the whole scene. sad. Okay. Not a

07:47 And when we look at a cross looks just like big difference here is

07:52 you've got um private flats in. don't have it in because we don't

08:01 the title what we have in Galveston's wind tidal flats. When there's a

08:06 wind that comes in, covers the of the, but no real

08:13 significant titles. You see the appropriation started, Well 3600. The

08:24 Ah but before we leave this, how deep the sand extends,

08:32 how thick it is. That this basically about 25-30 ft of sand.

08:42 the trick here is to not compare like this, but to compare it

08:51 terms of the actual um, So we see how much less the

09:00 has pro grated. Now the sand deep. Um, should be a

09:07 , but um, we get a deeper sand here here. Um we

09:15 offshore. The sands as it turns , extend the deeper water depths in

09:20 atlantic. That has to do with energy. But why did it program

09:28 in the gulf of Mexico than in atlantic Again, the answer is wave

09:34 . Uh And maybe sediment supply. know we got a lot of our

09:39 here from erosion coming from Mississippi. hey, quieter lower wave energy,

09:51 tides is getting its rate of procreation we have here. These are global

10:00 climates again. Um And oh and reason I want to show that is

10:07 gonna look over here into um a energy California environment. Um This is

10:20 . This is this is four. I think it's fair to say that

10:27 is the way I've been using it for short face. That is where

10:33 have laminated sands above the beach, the beach deposits, bio debated lower

10:42 phase extending down to about 2025 8 . Okay, again, this is

10:54 wonder way face this, let's call uh Storm wave base, recognizing that

11:03 kind of generals compare that to California place in a much deeper and really

11:19 simply is that the wave energy is . So the vertical sequences might mimic

11:27 other. But because of the difference wave energy, uh you have a

11:34 different reservoir. Very different sand Now let's go into even higher energy

11:44 where we get up into Washington. . Face, They don't appreciate 10

11:59 . Ah we've got Primary sedimentary structures about eight years In core. We

12:09 what would be the lower short sending it out 30 and we see

12:18 pro gradation. Uh this Of about or 4 km. So this is

12:33 the right section notice here we got is offshore changing dips and the change

12:47 primary to cultivated structures. Okay, what we're looking at is again this

12:58 north face offshore. So what's causing variation question here And I pretty much

13:08 answered that question. It has to with wave energy, the depth of

13:16 weather and storm wave base. So get a much deeper thicker um Sand

13:26 and actually gravels in part in the fall area because of the very high

13:32 wave energy in the roaring 40s. that appropriating section we know the

13:44 this was drama short programming short face it's the same issue. We get

13:50 same kind of heterogeneity and a barrier . Short face, skip this.

13:55 to them. So let's look at we might take a barrier island in

14:06 into architectural conformance. It's not just place. Very important. Short place

14:12 certainly much of the there's battle appropriated with Phil this is wash over

14:22 There are flood title politics and politics . So we're gonna take this barrier

14:29 and divided up into components, each which has a characteristic component. So

14:39 of the big differences And intimate when get into higher energy, pick the

14:56 tidal energy. The deltas become really large. When you look at,

15:04 can see and it's a little harder see for all of the March

15:12 But basically this is what you're looking in that mixed title area. So

15:21 would be sitting in these are deltas then the flood tidal deltas are in

15:32 , but they're largely covered with large . Okay, so let's look at

15:42 shape of the barrier islands and how related to these title deltas. I

15:50 point it out, but when you at the shorter stubby barrier islands of

15:56 mess. A title or mixed energy , they tend to be drum ship

16:03 bowls at one end and kind of . So you could kind of imagine

16:12 like that. Okay. And the for that is because there is wave

16:26 coming in around that. No, title belt. So it's spinning the

16:34 raised and it's actually reversing the longshore . So there's a point here

16:42 But here it's growing. Yeah, currents. Parts of the south

16:51 there's a local reversal down for uh current. So forming this. Now

17:04 uh is this is being a But wait the fraction a rabbit.

17:21 . If we look at this this barrier island is offset with this

17:33 that offset is related to the up bro of that barrier up. we

17:43 see that offset in some of our um islands as well. Here's

17:51 here is the flood title entitled Delta to building jet esque. So we'll

17:59 back to that here. We've got drumstick model. Okay. And let's

18:06 at what's going on right down sediment is coming down and there's little

18:15 here and there's a lobe of sentiment , that little channel is bringing sediment

18:25 the uh bang. And there's also little channel bringing sediment and water into

18:40 day. All that water has to come out someplace which comes out in

18:44 middle. So there's a little blood channels on either side and the main

18:56 channel in the middle. So the moves in and out and is deposited

19:03 the ab as this subtitle dealt and moves into the bay and is deposited

19:11 a flood title Delta. Okay. so this area would show dominantly onshore

19:19 flood directed currents, predominantly directed And here we have an example,

19:30 flood ab deposition. And you'll notice are, first of all, they're

19:40 breakers are occurring on this because it's shallow, but there's individual squash bars

19:49 are forming in the breaker zone in area here and they're moving sediment back

19:56 the beach, especially on this Okay, Now, as that spit

20:04 accreting it's bringing sediment into and covering laterally migrating chin. So here's the

20:19 channel. Now this is the here's title channel. Um This title channel

20:31 it migrates I guess. I can hear better. It's gonna have a

20:43 um spit us sandstone, Here's ball roads. 1851. I had a

20:54 working on this. There's a channel . The channel here, this flood

20:58 , this is dominated and this is cap and there's these little eyes

21:06 those are squash boards. So we a much larger EPT title delta than

21:12 predicted by uh models uh for micro environments. There's a lot of water

21:19 coming in and out of uh that and the two reasons for that one

21:25 we've got a big Allison day. there's a lot of title exchange.

21:30 other is that we get very strong coming in that flush a lot of

21:35 out. And so that f title is uh grown larger because of the

21:45 of the hurricanes or rather the northern well. Okay, we also have

21:54 entitled delta. It's now pretty much . Uh Pelican Island is now a

22:04 made island, but we can see this uh eb title delta would have

22:11 like by looking at suddenly is past is where the uh where there has

22:17 been the jetties developed. So here have down current pro gradation of the

22:28 and down current migration of the so we have the inlet turns out used

22:37 be over here and then it gradually filled. And then it's gonna be

22:46 again, This portion of that barrier is actually mainly inlet filled. In

22:56 , their barrier islands where 50% of core of the island is actually in

23:01 field, not programming short face. , so here's our dip section,

23:11 straightforward. Here's our strike section and , here is our lateral migration.

23:22 there's going to be a cap up , it's gonna be from the beach

23:28 sure if it didn't but below that gonna all be inlet channel related

23:35 Okay, this is maybe a little realistic version showing that spit cap sitting

23:42 top. Um Here is a P. G. P. R

23:51 diagram annotated diagrams showing the end of in this spit cap. Uh Here's

24:00 one that completely filled. Uh it migrating like this. Okay, so

24:07 the vertical sequence. And remember got . In fact, let's do it

24:18 , here's our inlay. There's a blood dominated chance a deep abdominal

24:30 So here's the floor, the deepest will be those sediments deposited in the

24:40 channel. They'll be the courses they will be predominant, there'll be

24:46 be title bundles but they're gonna be . Then we're gonna have actually probably

24:52 little erosion and a shallow flood dominated and those will be migrating in this

25:04 , whereas these are migrating in this . And then we've got this pit

25:12 , which is essentially the course, sentiment spilling in the top of the

25:19 filling filling into the channel, actually the top. And then the spit

25:27 . So what are we gonna see we're looking at this uh channel

25:35 Looking at this programming shore face versus laterally migrating inlet fill or the programming

25:47 plane like this is uh you're gonna some breaks. This holds for both

25:58 planes and uh barrier islands here we've got in left field is oriented

26:12 to the strike. So they're the continuity is at right angle to the

26:18 line here. The flow continuity is parallel to the shore. And so

26:26 is an example again of that in field. Now, here's the barrier

26:36 . And here is that inlet fill , much more, much more lateral

26:47 than the width of the channel. . And this cross section is basically

26:54 face, the flood title delta. hard to to really differentiate it.

27:05 the F channel is coming out through . The flood deposits are coming in

27:15 and then they're coming back, both kind of like little levees and

27:21 Uh And so it's it's a very pattern, but you can see from

27:27 that there are lobes that are being from the flood deposits. And there

27:37 robes being deposited by the ebb deposits well. So here we have what's

27:46 an em shield. Yeah. And is coming in this direction, The

27:53 flow in this direction. Um This called the flood ramp shield channel.

28:00 these basically have different kind of is based on the segmentation of the

28:08 delta. Okay. And we have of our students uh doing masters

28:13 looking at the present sand and And uh it's hard for me looking

28:20 sedimentary characteristics got proximal range difficult. this ranges from 35. But significant

28:39 sorting brain size, eunice. So a major change in texture as we

28:49 from the possible. That would have implications for patrolling characteristics. Say it

29:05 ? She did. Yes. Uh And basically they're like little can

29:10 . So we're only sampling the Yeah. Okay. Uh So what

29:18 look like? Well, it's it's always clear. Um We know it's

29:23 be a kind of a low bait um connected to a laterally migrating tidal

29:31 . We know there are flood ramps em shield. So there's gonna be

29:40 variations in the channel from the channel flood and ebb deposits. Okay.

29:52 then we get into the lagoon. we don't have a great model for

29:57 , but this is the best we , which basically shows the channel Blood

30:08 blood ramp. And that's gonna be dunes. They call sand waves basically

30:15 and then we get into the ebb moving back offshore again, get a

30:21 of title bundles and you're gonna get throughout the whole thing, but generally

30:26 upward secrets with the these characteristics reactivation , mud drapes, title bundle,

30:33 dominated paleo occurrence, rounded, sub , well sorted sand stone. And

30:40 as we look into uh this we're uh not only well sorted, but

30:49 oh much. Uh we're changing skins ketosis as well. Okay. Uh

30:58 this again is a kind of model Galloway. This is based on field

31:05 . So this is the best we've for what? That uh flood title

31:14 . Well, that's all fine and for regressive speech trans plane or

31:21 What happens with the transmission system? here, the vertical sequence is gonna

31:26 basically lagoon to March to flood title to Russia and maybe some beach

31:40 Um this is all erosion. The is here, there's wash over sand

31:48 , but then we got to look and of course entitled no changes as

31:54 . So this is an erosion of of color ravine would surface. This

31:59 the only place where we get sand the beach and then we do get

32:05 in the title and and the flood Delta, but it's a very different

32:11 than we get with a pro rating . Okay, now this is a

32:21 stand to a forest regression dropping to low stand and then sea level

32:29 this whole surface is being eroded, is a little bit of wedges set

32:33 right here. This is the wave service. There's a little bit of

32:39 deposits out here but the great So this was the pro grading system

32:47 here we are today at an erosion . So this is that surface during

32:54 C level. It rises and erodes erodes until finally what we see is

33:02 little accumulation there is way off here over here we get wash over being

33:08 here. Storm deposits here, but ravine and surface a wave ravine and

33:15 here, if you have low accumulation and not a lot of rise and

33:22 it, you're gonna have something looks this. If there's more accumulation rise

33:30 sea level, you're gonna get a of scent. It's called a back

33:35 wedge. And that's gonna be where wash over laguna. All deposits are

33:41 to be uh flood title deltas, deposited. That's what we see

33:47 And notice below that ravine mint there are a few abandoned inlet

33:52 Remember that inlet is deep and so may not be completely truncated when sea

33:58 rises and the waves now as that level is rising, we sometimes will

34:07 see a drowned ridge and develop a and then that barrier is cut off

34:14 we see a second barrier. So can have barriers overstepping, we can

34:22 oops, um barriers vertically. Accreting on the rate of sea level rate

34:30 sea level rise and sediment supply, , until finally it's jumped over.

34:37 we actually see on the shelf that the last rise in sea level,

34:44 were periods of time with their little islands that were then jumped over.

34:50 much of the thought is that barrier initiation is one of two ways spit

34:56 moving in laterally or basically being nuclear on a topographically high area. And

35:07 just, you can read that at lesion. But this is what a

35:13 beach looks like. These trees are dead because they used to be behind

35:19 beach. Their now exposed that marsh All you're looking at is a thin

35:27 of set right up against the We saw that with Hurricane Alicia,

35:35 Carlo, the same thing, the is flattened and if it continues to

35:45 , it'll just work his way back no net sand. Uh Coming

35:52 Now when it's being eroded, we get breaches within the dooms that give

36:02 these wash over fans and notice this area here is a wind tidal

36:08 I said we don't have tidal We don't have astronomical tidal flats.

36:13 , so here we've got this wash fan that looks a bit like a

36:22 delta, but it's not Titley It's driven by a single or multiple

36:30 events and at some point they're healed they may or may not be

36:37 So here we have carla before carla a lot of breaches and these kind

36:44 wash over lobes. Okay, erosion now they're all healed again.

36:55 The other thing we see in the part of texas barriers with these wash

37:00 is we see reworking by waves. can have some pretty big bays and

37:09 can have some pretty long fetches with winds through the northern and so we

37:13 have a reworked sandy fringe on the side of the island. Now,

37:22 you look at these wash overs, , they can wash over into standing

37:28 of water or they can wash over marsh and you can think of them

37:32 much like crevasse plays. Uh The is, they're not, well,

37:41 tend to be deposited in shallow Uh if it's deposited in standing

37:47 you get four sets. If it's on a marsh, it's gonna be

37:51 horizontal stratification. So this wash over if you like, was deposit in

38:02 water where the back part of the was was flooded. Now, Galveston's

38:10 largely a regressive pro grading barrier Most of the barrier islands in texas

38:18 transgressed like Matagorda peninsula. So if compare the two at the same

38:24 First of all, we recognize there's a break here that might represent a

38:32 shore line. And if we look the present transgressive shore line of Matagorda

38:43 , we see that it's so narrow is constantly being reached and fringed with

38:49 overs. Galveston Bay used to look Matagorda Galveston island used to look like

38:57 Island. Yeah, there were breaches the dunes, there were wash

39:05 But as it pro grated, those overs basically became less and less

39:14 So we have an abandoned transgressive barrier by a until very recently and actively

39:25 barrier island. So here's our inlet , here's our regressive barrier model and

39:36 our transgressive barrier on money. These simplistic, but they're useful things that

39:44 of store. Okay, so going to those barrier island components, here's

39:50 pro grading shore face. Here's our over fans and here's our title in

39:59 you should be able to in reproduce vertical sequence of sedimentary structures coincident with

40:09 three settings. Now, in if we step a little farther and

40:16 look at other parts of the wave shore line, um here's a wave

40:23 delta and here's a pro grading short . They're both kind of funnel shaped

40:33 upward, deposits. The big difference that there, the wave dominated delta

40:45 going to have a lot more separated because it's getting a lot of mud

40:51 in, it floods. So it's muddy your face, mud and flood

41:01 in waves. We don't get that because we just don't see much mud

41:07 into the system. Okay, so the first difference. Um The other

41:14 is as we go farther offshore, we're doing is we're getting into more

41:18 a distal phase where we're just getting offshore to most distant shore face

41:28 we're getting a distributor or a distributor in the in the delta here,

41:34 getting a pro grading in the we're getting washed over fat.

41:40 so think about how these different components going to have different vertical sequences and

41:51 those different vertical sequences may have different characteristics. The last modern study is

42:02 in here. These are more stubby islands. Um This is in a

42:07 high title range area. It was studied based on core as well as

42:18 and it turns out that it's got rather more complicated history. Okay,

42:28 we've got transgression occurring along here. we got a regression occurring. We

42:39 a little bit of a transgression More regression and dunes. Now,

42:48 telling this story probably wrong, but point is that within the holocene,

42:55 gotten a series of transgressions and regressions well as vertical accretion due to aeolian

43:05 as our pro grading shore line has back and forth. So the geometry

43:14 this section here is really quite complicated it maybe explains why in this case

43:22 the pro grading strand plane in there's so many interruptions because that represents

43:32 long period of time. Now, of the best studied field areas is

43:40 the field formation that sits in the uh my scene legacy. I think

43:52 the legacy. The legacy in section . But um it's between two big

43:59 And it's got over four billion barrels oil in place. Most of the

44:06 are up, dip strata, graphic . So as this thick section of

44:12 islands that vertically created over Over 2000 there, it's been tilted with basin

44:21 . The oil is going now and into the finer grain lagoons and coastal

44:27 deposits. And a very nice study unfortunately is not available on pdf is

44:33 U. S. G. I'm , a Bureau of Economic geology

44:37 looking at these components and this is cross section. Look at the vertical

44:44 . And you see here these little that's the foreshore, we see over

44:54 we have wash over deposits here and , all deposits in between Laguna and

45:02 . So we've got pro grading foreshore wash over deposits if we look at

45:08 field. Um It's a little hard see, but the the ice Apax

45:16 to run like this and like this then like this again. And then

45:24 kind of split up. No surprise we're looking at is shore line,

45:34 gradation and inlet fill in shore line gradation in a flood town of

45:46 And when we look at it in , uh you get a little better

45:51 for um, the variation in permeability , in the core programming shore phase

46:02 2 to Darcy's in the inlet fill from less than one darcy to the

46:13 being more than two million horses. let's look first of all at that

46:21 core that's going to be pro grading , lower shore face, upper shore

46:29 horsing upwards. And here we have migration with the channel floor finding

46:40 then coarsening upwards as we get this or spit accretion. And if we

46:47 at the best permeability, ease, see them in upper shore face

46:55 lower channel fill here and in the elongation. And there are local periods

47:04 this channel has good or a stick . And we see the same thing

47:11 here. This is saying the same . There's another barrier island, that's

47:19 glass block sand really thin. It's transgressive barrier island with wash overs is

47:27 like this. It's Mustang island. the glass hawk is mustang island,

47:38 41 8. It's Galveston island. so you see as these systems have

47:47 created through time, they've given you various degrees of permeability for the reservoirs

47:55 of course the up dip cap for photographic trap. And you're looking at

48:01 of barrels. Okay, we're gonna here because what we're gonna do next

48:07 get into estuaries and I'm not gonna that or if I do, I'll

48:11 it on friday, but for the exam will cover through barrier islands

48:18 I'll have to decide whether or not hack on estuaries or, and estuaries

48:23 Delta's. Okay, so let's put

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