| 00:16 | look. Okay, let's talk about water again. There's a lot of |
|
| 00:23 | references, and this isn't completely up date. That, uh, remember |
|
| 00:27 | ones that have diagrams that your thinker . Okay, uh, when we |
|
| 00:33 | about deep water, resource is this old, but they've really taken |
|
| 00:41 | really? Since about 95 on. , but one of the points I |
|
| 00:46 | to make is we needed distinguish between water water in deep water, deposition |
|
| 00:56 | . When we were in, let's , wanted Epsom 205 100 m. |
|
| 01:03 | of the deposition systems were shallow, and flew 85%. But by 22 |
|
| 01:11 | least, uh, during that same of time, Um, in the |
|
| 01:18 | deep. Greater than. Well, me rephrase it. In the deep |
|
| 01:24 | greater than 500 m, 91% interpret stand stills. So we've gone from |
|
| 01:31 | in pretty deep water, but still water deposition systems. So looking mainly |
|
| 01:40 | , and very deep water with deepwater systems and recognize that turpentine sandstone is |
|
| 01:49 | kind of general undisturbed for a lot departures. Instant systems. Okay, |
|
| 01:56 | we look at that transition from shell to DePorter in Angola. The same |
|
| 02:04 | in Brazil for saying the same thing most of that for much of that |
|
| 02:09 | pre salt. So one distinction I make with respect to with respect to |
|
| 02:19 | recently is that a lot of the deep in Angola and in Brazil is |
|
| 02:26 | sub solved. And there we looking at deposition systems that are relatively |
|
| 02:32 | , including the custom alluvial fan and like. So most of what we're |
|
| 02:38 | be looking at or things that are sold associated with the Paleozoic to Simmons |
|
| 02:46 | trailing edge margins off the Atlantic coast the most part, a little bit |
|
| 02:51 | Indonesia. Okay, now, if look at it sandstone, we look |
|
| 02:57 | settlement delivery looks sandstone Ridge Force. said, we're interested in how that |
|
| 03:05 | got there. And so we have about the impact of source area and |
|
| 03:12 | where it can be to cause Hiestand shorelines, low stand shorelines. |
|
| 03:17 | really now are getting into that portion the system. We're looking at deposition |
|
| 03:23 | sedimentary Grammy flows. Debris flows high low concentration tribute occurrences center. So |
|
| 03:31 | look at those. And we can general, talking about these three variables |
|
| 03:42 | source and supply regional tectonics. And pretty much going to be what's controlling |
|
| 03:52 | things that control, uh, deep sanitation. We'll get into that |
|
| 03:59 | were directly but will be dealing with indirectly as we go through now, |
|
| 04:05 | of the things to look at when look at slope and deep water or |
|
| 04:10 | type of margins so we can have pro grading stable margin or a pro |
|
| 04:16 | unstable. And this Yeah, we've about this that previous lecture we talked |
|
| 04:24 | stable shelf edges and unstable shelf Most of the reservoirs today. This |
|
| 04:33 | actually today there's about 2010 most of deep water reservoirs you associate with pro |
|
| 04:39 | unstable margins. Okay, a lot that has to do with traps. |
|
| 04:44 | also have margins like, uh, the the west coast of Florida. |
|
| 04:49 | a retro grading margin. We've got margins that big failures. Okay, |
|
| 04:56 | got compression on margins. You've got all margins. Okay, so |
|
| 05:03 | we look at tectonics. We're looking tectonic Lee. Active margins move. |
|
| 05:09 | , extension and compression allow and then would be the passive edge margins. |
|
| 05:17 | , again, this prima says the thing that most of what we're looking |
|
| 05:22 | here is mobile bit extension, Throw mobile bed contraction and you're looking at |
|
| 05:32 | of the reserves to date. And are these two here. Okay, |
|
| 05:38 | a new interesting article that I would you to. I'm introducing it early |
|
| 05:44 | the lecture because what it does is kind of gives the workflow as to |
|
| 05:49 | we're doing what we're doing. And starts with the little fishies of specific |
|
| 05:56 | , the description of massive sand lemon sanit central and is putting them into |
|
| 06:04 | elements and stacking them, um, see what that vertical sequence looks |
|
| 06:11 | And then from that defining larger architectural like distribute terry channels, lobes, |
|
| 06:20 | friends to create that model, your interest and then from that, be |
|
| 06:31 | to model the reservoir. Okay, that's where we're going. And that's |
|
| 06:36 | we started down here. And we've building up to create these three d |
|
| 06:46 | worse then, when they want to for either exploration reserve. Uh |
|
| 06:52 | Are, uh, production modeling now we look at DePorter systems, there |
|
| 07:01 | a surprising unity of architectural elements that find in almost all settings. There's |
|
| 07:08 | be a inside shelf and canyons, then there's going to be a slope |
|
| 07:15 | will have channels and levy channels. then there is a Siris of distal |
|
| 07:23 | and basic floor fans. This simple model explains most of the deposition settings |
|
| 07:36 | we're gonna be interested in. And thing that is similar is that in |
|
| 07:45 | of succession of events, we get failure to form a canyon. The |
|
| 07:55 | trap sediment. The settlement is bypassed form a fan, and then the |
|
| 08:06 | stage is, Ah, bad judgment back filling of the channel and fan |
|
| 08:12 | Channel Levy complex in him a classic . Again, this succession of events |
|
| 08:20 | similar just in a lot of OK, now we've talked about |
|
| 08:25 | I haven't used these terms, but useful. We can talk about triggering |
|
| 08:33 | for her sentiment for gravity flows. there are united flows where is instantly |
|
| 08:40 | by either earthquakes or overstepping and change poor pressure. Rapid sedimentation, |
|
| 08:50 | and not ignited where we have long introduction of high concentrations of seven, |
|
| 08:58 | , typically and river mouths, but , in some cases, my under |
|
| 09:03 | as well. And as we've seen and will Seymour. Now, those |
|
| 09:07 | types of mechanisms give us very different of sands insane stones. Okay, |
|
| 09:15 | when we talk about deepwater face, We typically talk about the channel |
|
| 09:22 | which is going to include letting over deposits. We talk about a deposition |
|
| 09:30 | , which is more or less sheet , and we're gonna look at mass |
|
| 09:35 | complexes. MTC uh, there are other things loaded loaded to the |
|
| 09:43 | I feel, and sheets kind of into these, um, but we're |
|
| 09:49 | not spend much time on this or rise for heavy plastic drinks, not |
|
| 09:56 | they're not important, but they're not important. And I'm running out of |
|
| 10:00 | . Okay, So if we look these, uh, types of |
|
| 10:06 | uh, the slumps or now referred his mass transport complexes Uh, the |
|
| 10:14 | flow deposits are now Deb rights. nights are broken up into Hi, |
|
| 10:21 | sitting, lowest density and classic Different terms for that contour rights and |
|
| 10:29 | . I Actually, I don't know they mean by that, but we're |
|
| 10:31 | pretend like I do. And we're ignore contracts as well. Okay, |
|
| 10:36 | let's look at the so called classic . And if one that has the |
|
| 10:44 | . So the idealized balance secret says learn from sophomore level geology. Maybe |
|
| 10:52 | is a basal t a massive graded a T B plane. Parallel |
|
| 11:02 | a T c Ripple a TV upper laminate in a t e. But |
|
| 11:14 | , so that is the complete Balham . OK, But in reality, |
|
| 11:20 | is only part of this spectrum, what we know now is that a |
|
| 11:27 | flow of them can create the beginning sediment transfer English. The sentiment is |
|
| 11:39 | . A slide to the slump, the debris flow to the turbidity current |
|
| 11:44 | night. And even within here. , Dan. Stay low density community |
|
| 11:51 | . Now that transformation usually becomes be , it becomes from Dennis to less |
|
| 12:05 | by in training water. So that's way to change the Realogy or physical |
|
| 12:13 | . But also, as the flow , it can become mawr. |
|
| 12:19 | concentrate. So one thing we learned quickly is that these models here are |
|
| 12:29 | stages in the evolution of an Okay, And this diagram here basically |
|
| 12:38 | with slump and talks about different things can happen, uh, way too |
|
| 12:46 | to talk about. But it gives good idea as to the multiple pathways |
|
| 12:54 | that settlement that probably started as, night. If event like a slow |
|
| 13:02 | be modified to form all these very . Okay, now we talk about |
|
| 13:09 | to grab the flows. We're talking fluid that is set in motion by |
|
| 13:13 | seven. That's to distinguish it from fluid gravity flow, which is sediment |
|
| 13:19 | in motion by the fluid. So everything we've talked about today, with |
|
| 13:25 | of the debris flows on alluvial fans behind pick NYSE are fluid gravity |
|
| 13:32 | I want to talk about seven You're granting flows, and in |
|
| 13:37 | one of the prime distinctions is what the mechanism by which that sediment is |
|
| 13:46 | in motion to support it. And varies from turbulence to hindered settling disperse |
|
| 13:54 | . Pressure to make your strength And that support mechanism is then supported |
|
| 14:06 | rather than characterizes different types. well different types, gravity flows. |
|
| 14:21 | so just to visually think about here's fluid motion where you got |
|
| 14:26 | Look, what happens is you increase concentration. You begin to have what's |
|
| 14:33 | 107 and that is that is the . Settle out. Water is squeezed |
|
| 14:39 | and intense toe working against the That's related. Liquefaction, too. |
|
| 14:48 | it. Pressure. Now we're down grain to grain interaction. This is |
|
| 14:52 | to the traction carpet overflow, And then finally, we've got so |
|
| 14:58 | fines that we actually have a matrix . There is a yield strength. |
|
| 15:05 | ? And this says the same Um, these are when I think |
|
| 15:11 | basically good visuals as to describe what saying. But now we're looking at |
|
| 15:19 | transition from low viscosity to hide discussed Newtonian fluids to non Newtonian fluids in |
|
| 15:27 | in plastics. And so we're looking something like this. Okay, |
|
| 15:33 | so what we talked about earlier with deformation is the result of applied stress |
|
| 15:42 | hell. The concentration settlement and the support mechanisms will generate different types of |
|
| 15:52 | transport in sedimentary deposits. Now, a long time, we've we've |
|
| 16:01 | uh kind of three, possibly four types of gravity. So deposits turbodyne |
|
| 16:10 | flow, which was starting out to a non cohesive sandy Deb, |
|
| 16:17 | grain flow deposits. And again we of it is maybe a non |
|
| 16:23 | He said, tip right. Clearly look different, but was for having |
|
| 16:27 | little trouble deciding how to classify And then finally, debris flows or |
|
| 16:34 | deprives. Okay, so we're gonna at these four different kinds of |
|
| 16:39 | and we're gonna break these up into others as well. So to do |
|
| 16:43 | , in particular, the turbid we need to look at a turbidity |
|
| 16:47 | , the process by which is too . So we got this density current |
|
| 16:53 | by the density and the density in , the result of high sediment |
|
| 16:59 | And he's got this very turbulent high head. Then this elongated body that |
|
| 17:07 | off okay, and we subdivide these tow, low density and high density |
|
| 17:15 | . My problem is, we can't really at what percent settlement I za |
|
| 17:22 | . Maybe it's five. Maybe his maybe 20 different authors states saying. |
|
| 17:26 | what's clear is that at some some increase in concentration. These low |
|
| 17:33 | turbidity currents change their behavior and become density turbidity, currents and deposit different |
|
| 17:40 | of Sepp. In fact, let's at this one. This is in |
|
| 17:45 | from flumes and feel work. We've low density turbulence suspension Then we got |
|
| 17:57 | higher density turbulence and spinach and there's and to and then down in here |
|
| 18:06 | actually got laminar inertial flow. that's odd is non turbulent Okay, |
|
| 18:16 | has this year string. So we go from a lower what will turn |
|
| 18:24 | to be a dead bride or something sheer strength to a high density |
|
| 18:30 | low density turbidity current. This is at the same place at one |
|
| 18:40 | No, this event, this turbidity is going to pass by that place |
|
| 18:49 | lead behind a record. And the of record is it varies down current |
|
| 18:58 | , very important to the relative importance these very of these three different layers |
|
| 19:05 | this now called tripartite gravity Kerr, get we have our degree flow high |
|
| 19:15 | , low density. Ah, The assumption is ah hide alot is |
|
| 19:21 | 20% sentiment, uh, 50% for flow intensity course your sentiment as |
|
| 19:28 | So there's a decrease in great size well as a decrease in concentration. |
|
| 19:38 | , so that thing comes by this model has at the very front, |
|
| 19:47 | amplitude waves were then buried by But this is a low density, |
|
| 19:52 | . Nothing else never had course or or more concentration. So what it |
|
| 20:00 | is it leaves behind a T B C unit. You get basically plainer |
|
| 20:10 | ripple. And then, of about drink tea. Okay. Now |
|
| 20:17 | , with a high density current, still have that little parallel zone which |
|
| 20:24 | or may not be preserved. Now have this high concentration, turbulent sentiment |
|
| 20:30 | then a lower concentration to live. , Hair is considered 10 to |
|
| 20:37 | I have no idea, really got numbers. But the relative numbers say |
|
| 20:42 | at the minimum, we have hindered so as a result. Now get |
|
| 20:48 | very bottom plainer unit. This actually something a little different is the third |
|
| 20:56 | unit. Uh, but daily got . You need to get our |
|
| 21:06 | and we don't have the TC here there's still such a high density that |
|
| 21:16 | don't have currents current rippling form. we have settlement just kind of coming |
|
| 21:22 | of suspension as a plane. so we've got two different types of |
|
| 21:28 | eyes. Depending on where there is high density turbodyne or low density |
|
| 21:35 | You know what you think about the flow and how it's going to |
|
| 21:42 | This goes downstream now. I don't these terms necessarily, but I like |
|
| 21:49 | visualization cause the first thing, he in sediment concentration, his greatest at |
|
| 21:57 | United event with the source of the . As it flows down slow, |
|
| 22:08 | , set in, a concentration gets and flow velocity is beginning to increase |
|
| 22:18 | it's getting a less viscous fluid. , matrix support is the dominant |
|
| 22:25 | and we've got this my sentiment. there's also grain degrade interaction as we |
|
| 22:31 | farther down and sediment concentration decreases. does matrix support, until finally, |
|
| 22:41 | dealing with grain to grain interaction. we continue tohave, decrease sediment |
|
| 22:54 | and we're beginning to have the velocity is turbulence is beginning to pick up |
|
| 23:03 | that the support mechanism of grain degrade , which would include hindered settling, |
|
| 23:11 | , is replaced with fluid turtles all while. Of course, that's happening |
|
| 23:17 | of this decrease in sediment concentration and in velocity. So down in here |
|
| 23:27 | gonna be where attorney nights are, they may very from high to low |
|
| 23:35 | when we get it here. This where kind of the middle ground of |
|
| 23:40 | Deb rights. And these are cohesive rights over here. So we could |
|
| 23:49 | at high density and low density turbine and look at the sequences. Look |
|
| 23:56 | the process. Is turbulence versus dampen ? There actually is a muddy turbid |
|
| 24:04 | can I'm gonna ignore, mainly because is the distance end of some of |
|
| 24:11 | turbid ICTs. Um, but the percentages was so less that we typically |
|
| 24:17 | bother to distinguish him unless you're an name. We have Deb rights. |
|
| 24:23 | clean. Sandy. Deborah. It's cohesive. I'm sorry. Non carries |
|
| 24:28 | . Muddy. Deb writes cohesive. then something in between. And |
|
| 24:34 | we'll kind of look at what they like a little later. Okay, |
|
| 24:40 | I'm going to try to use the terminology. A fine grain turbidity current |
|
| 24:52 | ICT a low density sandy German I a high density sandy turbodyne. And |
|
| 25:00 | I'm gonna talk about De Bryce and about non cohesive who he's Okay, |
|
| 25:05 | here's our I can't find grain. , here's our balance equals again. |
|
| 25:12 | ? And here is a complete dollar , which you will almost never |
|
| 25:16 | I have never seen one. uh, but Bama recognized that this |
|
| 25:23 | the idealized sequence. And really, he was saying is that this is |
|
| 25:27 | secret. Still, things may be . They'll never be out of |
|
| 25:32 | Okay? And we tried for a to describe this in the mid sixties |
|
| 25:44 | upper and lower floors. Okay? then this was, by the |
|
| 25:49 | within a year of the flow regime , making it turn the papers. |
|
| 25:57 | problem is, this doesn't work. no longer dealing with current in |
|
| 26:06 | driven slow. By the time we down to a, we're dealing with |
|
| 26:11 | support mechanisms and therefore other types of . So here's an example of the |
|
| 26:19 | A. And depending on whether or this is all part of the |
|
| 26:24 | it might be a t a Okay, So what is missing is |
|
| 26:29 | the entire top or everything between our Sandy. Okay, would be |
|
| 26:39 | Ah, here is a t be be overlaying by sea kind of |
|
| 26:47 | Okay, pretty common if that we think about that Complete probity, current |
|
| 26:56 | we can envision the loss of the . Or we could envision being loss |
|
| 27:14 | the top. Or we could just we've lost a little on both |
|
| 27:25 | Okay, so that's what these basically suggesting is we're going to see these |
|
| 27:32 | occur within a single turban night and taxis recognize? So let's look at |
|
| 27:41 | base cut out. Okay, He's throughout the whole thing. Hay is |
|
| 27:50 | out. That b is cut out center and what we're looking at is |
|
| 27:55 | transition down floor. And although it's proximal to distal, we've got to |
|
| 28:05 | that it's also a land. So could have that in a proximal setting |
|
| 28:11 | it was just spilling over laterally. , Like letting. So this is |
|
| 28:20 | of the the commonly seen ways Obama it early and how a turbidity crime |
|
| 28:29 | result in changes interpret ICTs and he it something like this based cut. |
|
| 28:37 | , now low Don Low, was working in California, and he |
|
| 28:44 | looking in coarser green, turbid ICTs a lot of what he saw. |
|
| 28:52 | , waas, particularly in gravels, in a lot of coarse grain deposits |
|
| 28:58 | things that were not bamba length. got destructions, escape structures. We've |
|
| 29:07 | massive beds. We've got, gravels and without any sedimentary structures, |
|
| 29:17 | a single ripple here, a single . Eso What he recognized was that |
|
| 29:25 | , he could find in his most section the Dow mystique was here. |
|
| 29:31 | what he really did was extend the sequence into lower, coarser composites. |
|
| 29:43 | what he said was that, you , this portion is the low density |
|
| 29:55 | I and then this, plus some stuff, is a high density turbidity |
|
| 30:03 | . Okay, so and then he on to show that, particularly in |
|
| 30:09 | you get a lot of face. that we just don't get in the |
|
| 30:14 | where Obama was doing his stuff. he began to relate the valve. |
|
| 30:19 | , Prince 22 different types. turbidity currents. And to suggest that |
|
| 30:27 | it doesn't stop at t a So here's the valve sequence. And |
|
| 30:36 | this is a slightly different Belmont Skip this because the secrets is the |
|
| 30:44 | . They just he just Addison come the main differences. He's put a |
|
| 30:51 | lamination down to the base. own that. There's some breaks in |
|
| 30:56 | size and that's about it. But look at that sequence according to |
|
| 31:05 | with respect to the high and low . Now he's looking at bottom cut |
|
| 31:13 | it again. But it's not until that you begin to even see any |
|
| 31:19 | the deposition of the lower concentration And combine that with now and you |
|
| 31:32 | that this is what he's added is portion here, Maybe this portion |
|
| 31:43 | Okay. And if you want to that deposits, imagine that Earthquake high |
|
| 31:51 | scour, decreasing energy deposition alone. , so from here to here is |
|
| 32:04 | scour. Very little deposition beginning We're beginning tohave deposition, but the |
|
| 32:09 | will be wrote erosion base and And from here on is only deposition |
|
| 32:17 | this decreasing concentration cloud. And so here the types of deposits we get |
|
| 32:27 | is refers to graph. So now have the possibility of Gravel's and then |
|
| 32:33 | have, Ah, a high concentration . We have base cut out Here's |
|
| 32:44 | Here's Bama's time to get way out here. We're getting the money term |
|
| 32:50 | , okay? And so this is the same diagram. Just looking at |
|
| 32:55 | differently. Those really fine grain, turban nights, uh, think of |
|
| 33:03 | as being kind of the equivalent. . See the E remember also that |
|
| 33:11 | E is broken up into, I mean mud draped from the event |
|
| 33:19 | then the hemming pelagic. And you tell that in part by the degree |
|
| 33:28 | probation but also reworked four AM zone and in C two deep water for |
|
| 33:37 | . People are microfossils in the upper . Okay, Now we've been seeing |
|
| 33:44 | mawr that, uh, supercritical flow occurring in these turbidity currents and leaving |
|
| 33:52 | record in terms tights and they are high concentration flow differently than low concentration |
|
| 34:05 | . And one of things I I have mentioned earlier is that when we |
|
| 34:10 | about sub critical and supercritical in really water, if it is the depth |
|
| 34:25 | the lower correct that sedimentary gravity flow is the age, okay? And |
|
| 34:35 | is looking at. And also we're at the relative density difference Delta density |
|
| 34:45 | the higher depth of the flow is determines the din. Symmetric fraud? |
|
| 34:50 | . So in the case of sedimentary flows, this is high density, |
|
| 34:56 | density. In the case of a channel, it might be salt versus |
|
| 35:05 | . Remember is we went from sub to supercritical flow in Oshawa Bar so |
|
| 35:17 | can talk about supercritical flow in both and in submarine curse. And we |
|
| 35:24 | somewhat similar things that is supercritical, jump sub critical. And we see |
|
| 35:30 | various types of settlement that are deposited the sedimentary gravity floats. In |
|
| 35:38 | we even see channels. And this something that we just has come up |
|
| 35:42 | the last couple of years where we get Chris en tick, the bed |
|
| 35:52 | that air migrate, and we also somewhat similar forms out here from to |
|
| 35:58 | out of the champ. Okay, red here, flowing first, was |
|
| 36:04 | this direction. The red is The green is deposition. What that |
|
| 36:12 | me is that the bed forms of up street. They're roading here, |
|
| 36:19 | here on backside. So that's what seen before. Erosion, that |
|
| 36:27 | Okay, erosion, Deposition can. so here we got within a submarine |
|
| 36:41 | within something that we really did not is a Siris of sediments that are |
|
| 36:52 | result of these upstream migrating percent event . Associative, supercritical term nights. |
|
| 37:02 | , so this is something that we recognized. Are these in terms of |
|
| 37:09 | ? Okay, so let's look at idea that we go from maybe sub |
|
| 37:15 | and self critical with a hydraulic Well, we've actually suspected that for |
|
| 37:21 | long time with her beauty currency, where there's a change in slope. |
|
| 37:28 | so where this jump is, there's , okay? And in a case |
|
| 37:38 | that, now, instead of a bed form, we're talking on |
|
| 37:46 | In other cases, there is a of things going on until such time |
|
| 37:54 | you develop. Hello. And so the lobe is detached from that break |
|
| 38:01 | slow, and instead we get rosia some DUIs. Okay. Where's |
|
| 38:10 | Here is just a little is filling little part of the shell. |
|
| 38:16 | what we've inferred is that there are efficiency and high efficiency. Turbidity currents |
|
| 38:24 | urbanites. A low efficiency is going be, um, not able to |
|
| 38:35 | transported long distances. And what helps transport turbid ICTs or sentiment over long |
|
| 38:45 | . A lot of money. So turbid, I can extend over a |
|
| 38:49 | distance. But of course, Crane I or that's a bed load dominated |
|
| 38:58 | curl. He's got on Lee be almost immediately. So thinking high |
|
| 39:11 | I suspended. Hi, I'm Low efficiency for locally. We'll come |
|
| 39:22 | this later because it it has to with going from channels toe lobes. |
|
| 39:27 | it's a It starts with this hydraulic and change in terms of where the |
|
| 39:34 | is being deposited. Okay, let's back to idealize sequence. This is |
|
| 39:39 | fine grain. Obama Long Deb. ? Slopper mainstream. Okay. And |
|
| 39:49 | here. Um, this is stuff from low, but it's just that |
|
| 40:01 | fine grain stuff was, uh, out. Okay, so we're talking |
|
| 40:13 | depth rights now. Okay. Forget current. Don't forget him, but |
|
| 40:19 | gonna look at that portion of the that is either matrix or grain to |
|
| 40:25 | supported of course. One of the of matrix support is the fact that |
|
| 40:32 | got a sheer strength. So we've these rounded couples that air floating in |
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| 40:40 | sandy matrix. Now, you might yourself, How did they get |
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| 40:45 | Uh, there's not. There is lot of grain to grain and |
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| 40:48 | but not when this being transported is Roy. These air basically river or |
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| 40:54 | are more typically beach and river deposits are being brought down. So the |
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| 40:59 | was at a previous cycle of Okay, so these then get into |
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| 41:05 | Deb rights. I'm mainly interested in end members with perspective very clean, |
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| 41:11 | or very muddy. Okay. And look at the sandy first, the |
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| 41:16 | cohesive sandy difference. We used to these liquefied flow deposits. And the |
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| 41:23 | is that they had evidence of water out and deformation that was due to |
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| 41:35 | . Okay, so these fluid escape are gonna be sometimes called pillars. |
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| 41:42 | betting is doing liquefaction. And these here call dis structures. Okay? |
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| 41:48 | you may or may not have something here. Okay, well, these |
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| 41:57 | are actually the result of water breaking these flat lamination, the great upward |
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| 42:08 | pillars. Okay. And this is , um, strategy or setting biological |
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| 42:18 | for this type of non cohesive Sandy . Well, here's an example of |
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| 42:24 | killer and example, like, this convoluted and notice down here. We |
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| 42:38 | have the dis structures as much. , but they This is an idealized |
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| 42:44 | . Okay, so, uh, think about what I was meant to |
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| 42:50 | was over here was supposed to be cohesive. Which is this Verses |
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| 43:00 | And here we gotta basil shower are . Yeah. May or may not |
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| 43:08 | great. In fact, in some , um, it will show in |
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| 43:14 | in normal grading random fabric sharp Over here, there may be a |
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| 43:22 | bit of erosion. Uh, not braiding. However, it may be |
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| 43:27 | little bit, but is thes sedimentary that are evidence of the non cohesive |
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| 43:35 | . Right. Okay. Yeah. a lot of cohesive Deb Roy deposits |
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| 43:44 | can be almost class supported. Almost all class. This is an |
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| 43:51 | for one. Okay. Oh, you get some unusual, particularly in |
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| 44:00 | , where the grain to grain interaction actually cause them coarsening upwards because there's |
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| 44:08 | lamination here. So there's a variety things that can go on in these |
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| 44:15 | grained sections. Okay, things to about clean Sam's massive clean sands can |
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| 44:25 | terminate. Is there, uh, deposited by liquefied debris flows? And |
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| 44:35 | more common in high density and small in the amount of mud can have |
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| 44:41 | differences on the floor behavior and the . Now let's take something in the |
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| 44:48 | . A mega turkey was not a guy. Even though the implication is |
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| 44:55 | this is a landslide. Submarine lands very top. We get reworking. |
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| 45:03 | this is going to be a something was failure, slump and then little |
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| 45:10 | at the top. And this is example. Okay, this is in |
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| 45:18 | Permian Basin. Uh, these are chunks of Permian reef deposits that collapsed |
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| 45:25 | with in two of the base in . So these are deep water |
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| 45:32 | Gravity posits sandy, and this is landslide that thought that if you |
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| 45:38 | Okay, now I don't know where notes and so what? I'm going |
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| 45:44 | do this kind of continue lecturing until a good time to stop the |
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| 45:50 | But if for some reason your notes there, you might want to get |
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| 45:54 | second Senate notes. Now let's go to this system. You know, |
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| 46:03 | hesitate to use just channel low because really more complicated than that. But |
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| 46:08 | really want you to think about is package of this face he's tracked, |
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| 46:13 | you like, from in size channels levied channels to a base in low |
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| 46:24 | these, uh, Galloway is big the low in ice Apax. |
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| 46:32 | they're useful. But I'm not gonna you about that, and it's |
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| 46:37 | I'm gonna try to look at the components of these complexes and, |
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| 46:45 | give you a sense of how to him. Case, Let's begin with |
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| 46:49 | upper part submarine canyons and sloping. we look at California was a beautiful |
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| 46:57 | canyon that actually extends within 100 m the beach. And then we've got |
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| 47:08 | canyons that never extend past the right, and some that extend past |
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| 47:18 | show prank. But don't make it the beach. Okay? So clearly |
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| 47:25 | a lot of erosion along forms, land form, but forms. Um |
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| 47:38 | are different in terms of their ability collect center. So let's think about |
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| 47:45 | slopes fatal and what that then results . You can either reduce strength or |
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| 47:53 | dress, and you can do that different ways. Uh, I'm not |
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| 47:58 | get in that look at this at leisure, but basically these airways that |
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| 48:02 | can initiate not just a turbidity but total slope failure. Okay. |
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| 48:11 | we talked about that earlier. We at The impact of it is shellfish |
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| 48:16 | . But we really didn't taking fine , because here's the shellfish delta. |
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| 48:22 | here is a major film. of course, out here is that |
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| 48:31 | transport complex. Now, in this case, there is back word |
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| 48:43 | retrograde, slumping, that is extending failure across the show. And in |
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| 48:51 | cases, that failure extends to the where it becomes he suddenly, |
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| 48:58 | Whereas others, they're just little failures the slope. Okay, so we've |
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| 49:07 | something like that thrown going into and we've seen something like that here |
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| 49:17 | you got a big something. Notice . The failure is occurring right at |
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| 49:26 | old shelf edge margin of a previous package and progres out fails. |
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| 49:35 | this they call him on is gonna the base over which that mass transit |
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| 49:43 | was formed. And then it Okay. And we see that here |
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| 49:55 | see a whole Siri's of large scale failures and resulting mass transport complexes. |
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| 50:09 | , really? So here's one of failures, either at an early stage |
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| 50:13 | one that never really made it onto show. And again, it's a |
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| 50:19 | is the submarine landslide that goes from to massive accumulation to a compression ALS |
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| 50:34 | over toe to maybe in fluid ized print. In some cases, we |
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| 50:40 | get he's out runner blocks for You have a block this being propelled |
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| 50:48 | a, uh, wet clay Okay, so all of this is |
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| 50:55 | mass transport complex. Okay, now, notice this. This is |
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| 51:03 | where it's this came from. It like it came earlier, but this |
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| 51:09 | published earlier. This is a flow initiated right off shore of a Gilbert |
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| 51:18 | delta. It's a Gilbert type delta is a marine delta forming in a |
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| 51:26 | Fiore hands very deep water. And one of the things we talked about |
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| 51:34 | Gilbert typed Elton's was that we often , ah re deposited material failure. |
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| 51:43 | . And this is, uh, become kind of a case study of |
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| 51:49 | they might look like. So actually is one in the subservience. |
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| 51:57 | is the breakaway scarf, and these Robbins. At first I thought they |
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| 52:06 | pressure ridges, but they're basically being apart. Here are some grooves that |
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| 52:13 | formed by a previous mass transport So this is for my lateral |
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| 52:22 | This could be a sub aerial and then it extends further offshore. |
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| 52:30 | , this is the toe of a , a mass transport complex. |
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| 52:39 | this is supposed to have been the thing, but the top of it |
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| 52:43 | here, and then it grazed down the toe. Okay. And if |
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| 52:49 | look a cross section here in me, uh, what we're getting |
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| 52:54 | here, that's basically that Those compression little thrust faults. And down |
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| 53:07 | we're getting some extension. Okay, is another case study. We're |
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| 53:13 | We're looking at the seismic expression of compression ALS ridges. And here we |
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| 53:21 | see someone out, okay? And were people for scale. Okay, |
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| 53:38 | , so we know a lot about transport complex is really from the |
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| 53:42 | So we have this blocking extension ALS . We had this hybrid, were |
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| 53:48 | extension, more deposition. And then , we have this compression also, |
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| 53:54 | that's pretty much the story for these and often their amorphous. It depends |
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| 54:00 | how badly broken up they are. used to assume these things were were |
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| 54:06 | and have no interest other than We now know that at least some |
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| 54:10 | these blocks can be sanding and can local reservoirs. The other thing we |
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| 54:18 | is that this topography that is set by this mass transport complex is an |
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| 54:33 | puts topography that tends to trip turbid . And so what we find is |
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| 54:41 | a lot of pondered basins in this region, okay? And just a |
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| 54:51 | reminder. Uh, these mass fingers actually, in their extreme, the |
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| 54:58 | events on the earth's entomological, because is the Amazon Canyon. Here's 100 |
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| 55:08 | and these are single or, at two mass transport complexes. They extend |
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| 55:20 | almost 1000 kilometers. We've got him the Gulf of Mexico as well. |
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| 55:27 | events are the events that har binge the harbingers of the creation of a |
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| 55:34 | canyon. These smaller events can be some cases, nothing more than a |
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| 55:44 | Onishi. Could be big slum, then just already have, too |
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| 55:50 | uh, the record of Ah, , uh, failure. Okay, |
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| 55:58 | , spent an hour. The timeto . Take break. Um, so |
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| 56:02 | going to do there. Um, will be back in five or 10 |
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| 56:09 | . So take a short break and me, uh, finalize this |
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| 56:17 | and then we'll |
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