| 00:03 | Good. Okay. Um You can me at W. W. |
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| 00:09 | W. D. You don't bother try to find me at the office |
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| 00:13 | vacated my office except for a computer doesn't work. So uh you can |
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| 00:20 | me anytime in our response as I . This is an example of the |
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| 00:28 | of the source material for example, at all. 2021. You have |
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| 00:34 | in your topics readings. Uh dollar 2010. FM. Four. You |
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| 00:42 | I'm gonna try to work out a where I get some PDFs of some |
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| 00:47 | these chapters. Um I don't have to give you those. Uh I |
|
| 00:58 | let you borrow them but I would that. You plan on buying it |
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| 01:04 | you're gonna keep that copy. But that's another story for another |
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| 01:10 | The other thing before I forget. this doesn't apply to Gloria. But |
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| 01:17 | I'm kind of hard of hearing. very loud. The A. |
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| 01:21 | So uh if you got a question a comment uh interrupt anytime, it's |
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| 01:27 | really an interruption, it's hard Right? But you're probably gonna speak |
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| 01:33 | particularly with. Okay, so let's about what we're dealing with with respect |
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| 01:41 | the topics of course. And the question is we're dealing with sediments and |
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| 01:47 | rocks. What kind. Well basically auto site or rather a talk thinness |
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| 01:54 | halak thinness and our toxin instructor derived within the drainage basin and the gelatinous |
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| 02:03 | are derived from outside the deposition of . Uh Can and if you give |
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| 02:09 | an example of a autochthonous rock or , rather just had grievances, courses |
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| 02:21 | walk out like derived from material that's from within the deposition basis. That's |
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| 02:34 | carbonates. Most carbonates are precipitated within deposition mark. It could be carbon |
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| 02:42 | blood, it could be a car skill fragment. Okay, a lot |
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| 02:49 | this material on the other hand, from outside the deposition basis. And |
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| 02:55 | we subdivide a locked in the sentiments to those that are to rigidness against |
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| 03:00 | name of the course. And that's alteration of pre existing rocks from outside |
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| 03:07 | drainage place. Uh And that's most set of if you're rock uh including |
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| 03:15 | you're conglomerate sandstone, blood stones and carbonates. So, can can you |
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| 03:22 | me an example of a carbonate that be a to rigidness? Rephrase it |
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| 03:40 | fragment of carbonate that was derived from the opposition base. So, you |
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| 03:55 | to be like working on the zone exposed. It wrote in um nice |
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| 04:07 | think you have any of you been filter to the Oakville Formation? How |
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| 04:15 | it still comes essay what that really . Is a sandstone composed of Calgary |
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| 04:26 | , basically fragments and it's a Miocene and it's sandwiched between sand stones that |
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| 04:39 | solicited plastic fragments and what it's doing reporting the uplift of the Edwards |
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| 04:47 | And so the carbonates of central taxes cretaceous carbonates are being shed off coincident |
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| 04:56 | the uplift of the plateau along the fault. And so what we see |
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| 05:04 | is first a carbonate seven. That to origins derived from the land. |
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| 05:15 | we also see recorded in the basin tectonic event. So often one of |
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| 05:23 | best records, sometimes our only record certain tectonic events are looking at the |
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| 05:29 | sedimentary basis. And so it's important keep that in mind. Now we |
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| 05:37 | classified power classic material as Trajan We're gonna ignore that. Um I |
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| 05:44 | a master's at UT um in I thought that was the only rock |
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| 05:51 | interest. I have expunged that from mind. And with any luck you'll |
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| 05:56 | hear that term from me again. , so we've got the original deposition |
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| 06:02 | but we also have plastic and solicit . Um without looking at your |
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| 06:07 | Can you any of you tell me your richness and plastic all at |
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| 06:26 | It's in the general plastic meat without geologically. So that was it. |
|
| 06:37 | , it's a class is a um it's fragmented material. In fact that |
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| 06:49 | what plastic plastic rocks are are basically no settlement from fragments of preexisting |
|
| 07:00 | So why isn't that true origins? makes them different? How about just |
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| 07:18 | this? Tell me what makes a rock potentially different from a originates |
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| 07:32 | Yeah, there was a classic rock be derived from inside basis. And |
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| 07:39 | think of any plastic rock that was from within the deposition race or said |
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| 07:50 | you friendship, um, welcome the . Could be shirt. Um, |
|
| 08:03 | from or, and uh, pretty . Our magic rocks that might be |
|
| 08:18 | arrived from the what about a What is a cocaine? Yes, |
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| 08:33 | . It's a it's a rock that of fragments of ship. Okay, |
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| 08:41 | you might see it at the base the beach party. Now, what's |
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| 08:46 | or solicit classic? That's basically plastic , but only consisting of fragments of |
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| 09:08 | , delicate minerals and rocks. uh, you're clay's your igneous sedimentary |
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| 09:17 | . Uh, those would all be classic. Yeah. What's missing? |
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| 09:26 | is carbonates and evaporate needs in order your non silica silicate minerals. |
|
| 09:36 | so each of these has a rather is to original classic in in Selous |
|
| 09:42 | has a specific meeting. And I'm assuming that you can figure that |
|
| 09:50 | . Your question rise. But it's , it is a matter of |
|
| 09:56 | And so we tend to use these that are changing. And so I |
|
| 10:01 | , you know, okay, I why this is a origen Isse course |
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| 10:10 | not a carbonate course. That's but it's a trajan its course and |
|
| 10:15 | necessarily a solicit classic course. now that I've said that I will |
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| 10:20 | in passing evaporates carbonates when I have , I will try very hard to |
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| 10:27 | those terms. Those rocks. Any that physicists, not a friend of |
|
| 10:31 | and I'm strictly a solicit plastic tourist guy. Uh, but be aware |
|
| 10:38 | , that's my bias. So, you think about the way in which |
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| 10:44 | classifies, basically, I'm at the of the triangle in the basis treats |
|
| 10:52 | come to here, we're going to Okay, now, but I want |
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| 10:58 | finish up on this first topic. really, uh, some of the |
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| 11:05 | concepts of sedimentary geology and so let's given one of the more important |
|
| 11:11 | Uh, the fact that when we at uh, the sedimentary rock, |
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| 11:17 | say, deposited down here, in the deposition zone, uh it |
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| 11:24 | just the end product of whole dispersal beginning in the source area where the |
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| 11:32 | is generated, passing through the transportation for the dispersal system and up into |
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| 11:40 | area of deposition. And so that we refer to as source to |
|
| 11:47 | How many of you have heard the source too sick? You have. |
|
| 11:55 | , Alright. And yeah, have you heard the term? |
|
| 12:02 | well, you're gonna see it more more if you choose to delve into |
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| 12:05 | literature or if you professionally get more in basins and basin in collections. |
|
| 12:14 | what we're concerned with is the fact everything that influences the score, whether |
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| 12:26 | happens in the stores and is modified transportation is potentially affecting what you see |
|
| 12:37 | preserved in deposition. So just as example, stable components, finding decreasing |
|
| 12:47 | source, in fact, one of themes that we'll be talking about throughout |
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| 12:52 | course is the role of, tectonics and climate on preparing the scent |
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| 13:01 | be transported on the deposition process, the sediment in transit and ultimately the |
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| 13:12 | environment segregating the settlement is in pieces unrecognized. So even though your goal |
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| 13:20 | be to interpret the environment of recognize that that is predetermined by a |
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| 13:30 | history of tectonics and climate in the area and transportation. Okay, so |
|
| 13:37 | is kind of in a sense on outline of what you think about when |
|
| 13:42 | look at a rock, uh that was influenced by iconic setting and climatic |
|
| 13:52 | . Source area modified by transportation deposited a sink and then altered by |
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| 14:02 | genesis. Now more specifically the tectonic controlled to a large extent the parent |
|
| 14:14 | that's exposed in the drainage basin and relative relief in the base that's going |
|
| 14:22 | affect the rates and types of weathering weathering products. Yeah, the climate |
|
| 14:31 | basically going to determine what type of products are ultimately available to be transported |
|
| 14:38 | by solution or by a bit salt either is dissolved ions or |
|
| 14:47 | Okay. In cleanse it. There processes and abrasions selected transport that can |
|
| 14:58 | both texture and composition in the environment deposition. The thing that will spend |
|
| 15:06 | time on is gonna determine the patterns types of deposition products and the geometry |
|
| 15:13 | the little fishies, die genesis, and die genesis with increased temperature and |
|
| 15:19 | . We conceive variety of processes altering original fragments and changing the interstitial pore |
|
| 15:29 | . Okay, this court will focus deposition system. We'll be looking at |
|
| 15:40 | precursors pretty much at every system. genesis will just be a passing |
|
| 15:47 | We talk about composition. Mhm. truth in advertising. Okay. Um |
|
| 15:56 | we use that. We sometimes don't know how to define the deposition environment |
|
| 16:06 | a geographic orgy. Uh I think should be geographic and or Geum or |
|
| 16:14 | area typo there characterized by distinct assemblage processes. Think of apart a |
|
| 16:32 | A deposition system. Here's a three body. I mean the sediment of |
|
| 16:40 | suite of processed related depositions. So we think about the flu viel |
|
| 16:47 | the flu viel de positional system. you think of one piece of it |
|
| 16:53 | might be called the deposition river is up the festival. If you were |
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| 17:23 | try to reconstruct that system, what might be included associated with deposition associated |
|
| 17:45 | ? I could ask the same Thank you darling. 10,000. But |
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| 18:01 | just if you're standing looking at a , that's all I'll say what is |
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| 18:08 | different. Thank you. Okay, are and close something that can be |
|
| 18:23 | . Thank you. 10 more phones the filter. Standing on the bridge |
|
| 18:31 | looking at looking south very soon. cut bang either which is gonna be |
|
| 18:43 | sure you need. Yeah their We are point guards and put this |
|
| 19:02 | there's a panel face so maybe a slide cutting through the levin. Those |
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| 19:13 | JIA Mortell components of that mobile Those are deposition environments. Uh The |
|
| 19:26 | face, she's been around for a time is basically a some of the |
|
| 19:32 | and paleontological aspects to try to graphic . Now take it down a little |
|
| 19:40 | into the logical structural inorganic aspects. the first thing. Again. 2nd |
|
| 19:49 | detectable in the field and or a she should not be something that at |
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| 19:56 | as determinants here in the absence of modifier should not be something that requires |
|
| 20:02 | to run an X ray analysis song most important prophecies is objective and field |
|
| 20:17 | that is it's not genetic. So shouldn't talk about a blue alpha. |
|
| 20:28 | okay it's a deposition system. Okay we may well have a fa she's |
|
| 20:36 | is a part of a flu real . Well but never confuse the interpretation |
|
| 20:44 | the observation species for observation and then gonna use species different types of species |
|
| 20:54 | make an interpretation as to origin. by the way this is the easiest |
|
| 21:01 | is the body of rock with specific because it's easier doesn't make it better |
|
| 21:09 | you need to remember that it the to be mythological structure. Organic and |
|
| 21:16 | got to be field based objective. most of what we talk about are |
|
| 21:27 | fishies. Okay. And so they describe what can be interpreted as a |
|
| 21:38 | within the deposition system. But the levy is not a fa she's there's |
|
| 21:51 | be some characteristic description of sedimentary structures textures and or organisms. Organic uh |
|
| 22:06 | is characteristic of. Okay, now turns out that concept is used in |
|
| 22:14 | whole bunch of things. What we what I as a geologist normally think |
|
| 22:21 | theses. It's really little facetious. the set of characteristics that defines that |
|
| 22:31 | union. They have similar pathologies. stratified, fine grained sandstone. |
|
| 22:39 | Uh huh. Maybe it's similar fossil . Um Econo facial also based on |
|
| 22:53 | fossil content. Trace false. Is were the body for this? Could |
|
| 22:58 | body fossils or that term is Seismic fe She's uh radar grams or |
|
| 23:09 | gpR fishies, fault fay. She's type of objective field based descriptor that |
|
| 23:23 | then be used to interpret something of can be broken up into the |
|
| 23:28 | She's okay. Yeah. You you're familiar with theses tracks that is genetically |
|
| 23:40 | interconnected co evil sedimentary faces. And this would be an example of |
|
| 23:45 | This goes back to that question of viel environments versus systems here we got |
|
| 23:53 | Phil point bar base these are all . We're gonna look at each of |
|
| 24:00 | can extract them and describe them. when we encounter this assemblage, we |
|
| 24:07 | recreate that environment. Now, one the ways we do it is by |
|
| 24:12 | fish and basically says the vertical sequence patients in a conform herbal such reflects |
|
| 24:26 | face. She's track or lateral sequence the time of deposition. Can and |
|
| 24:36 | could also change face. She's which descriptive. Who deposition remarks which would |
|
| 24:45 | interpreted the same concept. Yeah. actress is important conform a ble meaning |
|
| 24:57 | any significant erosion. All surfaces or gaps. Well, it turns out |
|
| 25:03 | got time gaps in the sedimentary record every inch set. So one of |
|
| 25:11 | things that we have to think about we look at reconstructing sequence of events |
|
| 25:17 | environments they're in is what are the is of the time gaps. And |
|
| 25:24 | that's a term. We'll talk Ok, so here we've got a |
|
| 25:32 | track. It goes from the but flats cold. Oh, water |
|
| 25:44 | mudflats, uh alluvial plains, uh , ground balance. And then notice |
|
| 25:53 | that sequence has evolved through time in section. So would that be a |
|
| 26:03 | or a regressive sequence based on what see here is the sea transgressing or |
|
| 26:34 | ? Maybe this will help because this walter's all this is actually this is |
|
| 26:43 | we are interpreting as the eastern. it a transgressive or regressive system. |
|
| 27:06 | . Right. What is the Yeah. Legend that correct freshwater |
|
| 27:22 | Okay, fresh water overlaying by Very. So the seas are coming |
|
| 27:38 | . They are transgressing the shore line we have this regressive, it's |
|
| 27:45 | Public transgress sequences are kind of uncommon using code. So I like the |
|
| 27:54 | now Holbrook and may all have a good um discussion among other things, |
|
| 28:02 | law and I'm not going to get it except to say that when we |
|
| 28:07 | about a an environment, maybe a , maybe in this case delta, |
|
| 28:14 | actually variability day to day, week week, year to year. So |
|
| 28:19 | can think of each of those environments having a distribution in space in |
|
| 28:27 | So when we look at the vertical , it's not a simply gradation |
|
| 28:38 | You have got these flights coming there's all sorts of things going |
|
| 28:45 | And so these, these are what refer to as local sample filters. |
|
| 28:57 | I'm not gonna belabor it except to when we interpret this, we have |
|
| 29:02 | recognize that that setting, that a lot of things are going on |
|
| 29:09 | are selectively being recorded in the rock . Let's look at a different patients |
|
| 29:17 | . Here's a wave dominated track from launch. Your we broke it up |
|
| 29:27 | different uh components the offshore your face . We'll talk more about that in |
|
| 29:38 | class. But we've also added a sedimentary structure that you might get in |
|
| 29:48 | of those sunk going from deeper water exposed to Julian. So let's take |
|
| 29:57 | faces cry and look at it in regressive or pro grading setting. So |
|
| 30:07 | we've done, whoops. So uh allowed the deposition. The moves seem |
|
| 30:26 | now we got off your bottom for for short face beach deposits and what |
|
| 30:38 | might look like is something like you know. And and notice again |
|
| 30:45 | these sand stones inter bended but These are so as that beach is |
|
| 30:56 | seaward is doing so methodical and all these are genetically related. But there |
|
| 31:07 | this That's funny in that conversation statements in this particular example we've taken a |
|
| 31:25 | . We called it a pair of . How many of you are familiar |
|
| 31:28 | your own pair of secrets you've heard it? Yeah. Yeah. I |
|
| 31:37 | like I'm not asking you to find I'm just curious if that. But |
|
| 31:45 | it's a confirmable, relatively concerned. important of genetically related sentence and they're |
|
| 31:56 | by major flooding systems. So it if you like a pro gradation pulse |
|
| 32:04 | Seattle capped by a transgression. Another . Transgression. The flooding surfaces usually |
|
| 32:18 | a rapid for relatively rapid rise in . So here beach deposit is over |
|
| 32:30 | it's the function. What is I mean according to Walters law, |
|
| 32:42 | is no place where a beach sits next to offshore deposits. So what |
|
| 32:51 | of sequence is missing in terms of . The transgressive system. Okay. |
|
| 33:00 | that's actually much more co gradation all are much more commonly preserved than our |
|
| 33:08 | systems because for the most part, in a high wave energy setting, |
|
| 33:14 | are erosion of transgressions. So it's until we get further offshore where you |
|
| 33:21 | actually get from shall our marine to marine transgressions. So here's an |
|
| 33:30 | You can see it um Aeolian offshore and here's our marine flooding service. |
|
| 33:43 | below this it went from Yulia to , the near shore option. And |
|
| 33:51 | this offshore near shore B. O. So these are pleistocene paris |
|
| 34:00 | preserved in beach terrace deposits in Now we've all heard the term and |
|
| 34:09 | the concept of the deposition model and its use uh it's a new one |
|
| 34:16 | comparison framework for future observations, prediction for interpretation. We take a lot |
|
| 34:26 | local examples. Filament model is for save in that fits here with modify |
|
| 34:43 | . Uh The problem is, it's getting to the point where every |
|
| 34:53 | world complex seems for our new Uh huh. They're multiplying like |
|
| 35:03 | the study of submarine fans. Almost models that are fans, we have |
|
| 35:13 | way too reliant on deposition marks. of the reason is it forces us |
|
| 35:26 | to try to fit what we see one of those models. And if |
|
| 35:31 | doesn't, well, we'll just make new model. Well, there's an |
|
| 35:37 | infinite variation in ways things can And so increasingly we're using a term |
|
| 35:46 | architectural elements who better both describe and the sedimentary record. Now on the |
|
| 36:01 | , we've got a major base and b thousands to millions of years of |
|
| 36:16 | record. And if we look at of the sandstone layers, we see |
|
| 36:21 | it turns out it's a series of bills. If we look at a |
|
| 36:28 | piece of that, which are a of river deposits, which can be |
|
| 36:35 | up into bars, which can be up into flood events. So flood |
|
| 36:46 | combined to form bars combined to form , rivers combined to form meander |
|
| 36:53 | The meander belt combined over the strata record to see. So what we're |
|
| 36:58 | to do is think of morphological subdivisions that deposition system that have distinctive betting |
|
| 37:09 | and assemblages. Little fishies. Mhm directly related to the main landscape elements |
|
| 37:20 | channels and bars and levies of that deposition system. And so we can |
|
| 37:27 | of a hierarchy of these things, channels, forms, etcetera. And |
|
| 37:37 | is going to allow us to build to regionals. So we're gonna piece |
|
| 37:48 | that deposition environment, that deposition the fish is trapped. But we're |
|
| 37:56 | do it by describing architecture helps now do that. We've got to recognize |
|
| 38:05 | they are defined by bounding surfaces, geometries and we can think of it |
|
| 38:15 | seismic symptoms. It's approximating a timeline that then allows us to develop a |
|
| 38:27 | of landscape developments. Eventually go back that, a leo deposition setting. |
|
| 38:34 | not a model. We have created description of our de positional setting based |
|
| 38:43 | what is preserved record. Uh Now earlier I said uh there are a |
|
| 38:52 | of time gaps for gaps in time . Um smaller properties down in |
|
| 39:08 | These little depths are events. Yeah. In fact, let me |
|
| 39:15 | the next no, here are short events. First. Has to do |
|
| 39:26 | etcetera. That might give you a Larger sense of ripple migration in the |
|
| 39:38 | site in the eight Spring site, 100 years light each of these where |
|
| 39:49 | a few Each of these thrive in recorded as a specific type of architectural |
|
| 40:00 | . So that's what our goal was to be able to recognize those architectural |
|
| 40:05 | and create that deposition system. Ah didn't you have heard of the term |
|
| 40:14 | , You have wheeler diagram, You another when I was an undergraduate, |
|
| 40:22 | basically it says, this is what see. This is how the sediment |
|
| 40:32 | preserved with time. So each of spaces is basically erosion or not deposition |
|
| 40:40 | a hiatus and you can see the ones convenience at what point it becomes |
|
| 40:50 | significant in conformity with respective authors Sometimes that's hard to say, but |
|
| 40:59 | of these packages is one of the where each of these periods of non |
|
| 41:07 | or erosion. Our boundaries are gonna us to find both the geometry of |
|
| 41:13 | green layer and its architectural levels. we take the surfaces. Look at |
|
| 41:22 | hierarchy looking sediment sheets, maybe seismic create developments by which we develop and |
|
| 41:37 | if we want a deposition mark. here is a model of the place |
|
| 41:43 | working on there. Maybe it's a of Reservoir 22 p. It's third |
|
| 41:55 | . Okay. And it may have to do with the four cents. |
|
| 41:59 | the sandstone in the next place. know, maybe it does, but |
|
| 42:04 | doesn't have to. So here's the model, the barrier system. |
|
| 42:13 | if we were to think about architectural , we could say, well, |
|
| 42:18 | how the core of that period. let's break it up short face in |
|
| 42:25 | field. Very report wash over fan , it would be sees when if |
|
| 42:33 | of these has a distinct geometry. with the fishies. Now we can |
|
| 42:40 | the same thing for rivers, places, etcetera. This is what |
|
| 42:52 | see and we can reconstruct it we can do the same thing with |
|
| 43:00 | sea settles. Okay, so this of architectural elements has really taken over |
|
| 43:08 | way we look, interpret sedimentary Okay, so what are some of |
|
| 43:14 | things that control the accumulation settlement? , there's some oughta genic factors intrinsic |
|
| 43:21 | the environment itself, lateral migration. river is doing that. Um channel |
|
| 43:28 | all rivers. Doing pro gradation of delta. That's basically the river. |
|
| 43:33 | its thing in its environmental deposition. there's also outside influences influences outside the |
|
| 43:44 | based changes and accommodation space, tectonic , Climate and climate change the biological |
|
| 43:53 | and changes there are changes incentive So those events ranging from a really |
|
| 44:04 | , really big Migration of ripple is type of architectural element. It's clearly |
|
| 44:14 | genic. The timing of major flood or clearly aubergine. Oh I'm |
|
| 44:28 | Auto genic within the basin. It's ripple or delta migration. Allergenic |
|
| 44:38 | Okay, so what do you My accommodation space that is the space |
|
| 44:41 | for accumulation? Well, it varies on what consistently looking at marine systems |
|
| 44:50 | mainly water depth in flew real systems mainly based level in the equilibrium profile |
|
| 45:05 | both cases tectonic change both in terms subsidence and uplift can alter the accommodation |
|
| 45:16 | . Science in basin uplift in the and all these can affect the accommodation |
|
| 45:27 | . This is just gonna let you at this on the phone, basically |
|
| 45:34 | sea level is different. Hispanic sea because relative and be changed. Welcome |
|
| 45:50 | . In addition, water depth is depending on deposition. And but when |
|
| 46:03 | say brother, you need to keep mind your static versus relative as an |
|
| 46:09 | . Now with the victor rivers. level is dutifully sealing city but you |
|
| 46:19 | change the base level but then the basin by the dam. Um They |
|
| 46:29 | . Uh huh. You can also it of course by changing relatives. |
|
| 46:42 | the easiest 1 to think about is regressive secrets. Steel level it's here |
|
| 46:53 | pro greeting. Very good step C sits here. The shore is transgressing |
|
| 47:02 | . R. Barrier systems each could during the austin sea level. Yeah |
|
| 47:14 | look completely different. So why is that some shorelines called gray and others |
|
| 47:22 | will. The answer to that is to the sediment budget. The sediment |
|
| 47:29 | is basically telling us how much sediments into the system versus leaving kind of |
|
| 47:43 | all the sources and sinks and The distribution of material over some time |
|
| 47:52 | now with respect to the beach. could also be a delta. There's |
|
| 47:56 | coastal set. You can think of as the rate of which settlement is |
|
| 48:02 | versus is being replenished. Which in simplistic way Is Marine Energy vs seven |
|
| 48:17 | . Oops. And the idea of budget is complementary to the idea of |
|
| 48:30 | sediment balance. Think of this as energy study with supply. If you |
|
| 48:42 | the sentiment supplier relatives await energy. shift towards education increased. I'm |
|
| 48:52 | increase wave energy relative to settlements So you can constantly change this relationship |
|
| 49:04 | . Changing wave or stream energy usually gonna well particular wave especially isn't the |
|
| 49:13 | change sediment supply could be technology could be said change So let's look at |
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| 49:23 | this is a barrier system but it also be appropriated strangler. We're gonna |
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| 49:30 | at the sentiment supply versus wave energy related accommodation space. Here's the case |
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| 49:40 | we have a 7th circle more sediments in concluded we have regressive programmed ation |
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| 49:50 | we have a settlement deficit where there's settlement and the waves are able to |
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| 49:57 | a small amount of sediment such as waves continually wrote them have a transgressive |
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| 50:06 | . Now in a case like you're in balance. So the accumulation |
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| 50:11 | receiving here is because of increased the space to websites, shorelines stable. |
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| 50:21 | basin is subsiding And so in Uh the free information in texas has |
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| 50:31 | 2,000ft war a vertically stacked barrier license the central part of south central |
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| 50:43 | They just basically kept going in this basin subsidence and part associate salt. |
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| 50:52 | one of the ways of one of useful ways of thinking about is this |
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| 51:00 | sea level emergence, relative sea level . Hi for basically uh follow the |
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| 51:14 | where there's high rates organization. What stable rapid fabled want to make here |
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| 51:34 | that there we could actually have transgression Singapore ST john we associate transgressions |
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| 51:55 | C loops regressions with Now is that one. So let's just look at |
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| 52:09 | examples. Let's just take regressions, sea level. Often accommodation space that |
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| 52:21 | no change in subsidence or uplift. so the shore line. Now there's |
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| 52:32 | there's a hint here and that is separating yellow, right? He's actually |
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| 52:43 | saying dominantly. Mhm. That one tends to be the death of which |
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| 52:55 | sand ist. And that one is , implying that appropriations occurred on the |
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| 53:04 | depth and baseball. That's what we a normal regression. And down here |
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| 53:22 | . Now here we've got a rise sea level. Yeah, we've got |
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| 53:28 | sand pushing yourself out. This is a quote normal regression, but it's |
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| 53:40 | very different because we see that barker a depth at which sand is deposited |
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| 53:48 | rising. And where does that Well that falls like i it's |
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| 53:58 | rising sea level and procreation. Not . And here we go. What |
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| 54:08 | called the four street rush blocking sea and regression. Now there's a there's |
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| 54:24 | error in this diary and it's a . I don't know which included, |
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| 54:34 | it has to do with the location that transition? Oh, mainly san |
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| 54:43 | make me look what's wrong with this . And give a hint. This |
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| 54:58 | what's wrong. What should it be ? And that first X Should it |
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| 55:17 | higher or low. And I And so what it should look like |
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| 55:26 | this. So this is what a progression books. Okay. And we're |
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| 55:35 | to use these transitions of fish eats fish short face versus offshore to reconstruct |
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| 55:48 | in base level changes in sea And maybe in for things like tectonics |
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| 55:54 | well as climatic change. Now, not gonna talk directly about sequence |
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| 56:06 | And having said that it relates to the things that we'll be talking |
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| 56:13 | That's you're basically looking at our cyclic in accommodation, space and settlement |
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| 56:22 | On the basis of this can form services so we can look at a |
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| 56:29 | track just as we could officials Mhm. And so we can talk |
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| 56:38 | different stages. Hi stan low stand Hiestand system track and what we're doing |
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| 56:49 | we will be doing. Taking pieces , find out overlooking at now since |
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| 57:08 | was in school and more specifically, since I've been teaching this course, |
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| 57:13 | seen a lot of advances in interpreting rocks. Gpr photo mosaics or whole |
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| 57:21 | section. Um, so let's just at a couple. We now are |
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| 57:28 | to see within the internal structure of . Why was that so hard? |
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| 57:36 | , sand dunes are dry and try dig into dry sand and it just |
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| 57:41 | with little information we had on these news was drive by some poor guy |
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| 57:49 | up water, pouring it on and it to maintain the boy's face. |
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| 57:56 | we can see the interior. What used to dig a trench until we |
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| 58:02 | the water table in uh channel No problem. We'll just run it |
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| 58:10 | the G. P. O. we can begin to see Things in |
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| 58:17 | dimensions perfectly modern. But also agent before we were restricted to a tune |
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| 58:24 | . You and we can even define . Talked about conceptual here are |
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| 58:33 | It's a great conversation now we put into station to that. Yes, |
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| 58:39 | defining the type of this case of street. Use ground based radar to |
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| 58:47 | a three dimensional image uh different strata units. We can use photo mosaics |
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| 58:59 | do allow us to correlate between measures they even used drone photography. |
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| 59:11 | aerial photography blake photography, unmanned aerial strokes. So this is completely I |
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| 59:23 | know if if it's exaggerating states revolutionized study of sedimentary rocks in the |
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| 59:29 | rocks in the field, but it has added the dimension we didn't have |
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| 59:34 | . Now. What is revolutionary? Besides, came soon we can see |
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| 59:44 | bottom shore of the bottom of the in ways we never could see when |
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| 59:53 | stuck to two dimensional parametric profiles. even more so seismic deal will follow |
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| 60:00 | where we're beginning to look at the geometry of seismic reflectors uh such as |
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| 60:09 | this from here. And we'll run trace through that. In doing |
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| 60:17 | we image the morphology of that particular . This is our face. She's |
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| 60:30 | by looking at aspect ratios of different of the seismic trace. And this |
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| 60:38 | us to now go back and do more detailed interpretation for seismic growth. |
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| 60:48 | an article that I would recommend you at is this one here. I've |
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| 60:53 | I don't think I included it within intro section but basically the geologic insights |
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| 61:02 | seismic dad and that truly has been revolution. Another thing is satellite |
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| 61:09 | We have access now to his studies over the world before we started using |
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| 61:20 | imagery. Alluvial family had about four five cases, case studies, alluvial |
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| 61:27 | . And as a result, our is limited. Now we've got thousands |
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| 61:34 | so particularly with the advent of the , uh we are increasing our his |
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| 61:44 | and our ability to quantitatively define the of our deposition systems. These are |
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| 61:54 | some of the source to sink areas we could look at. We're still |
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| 62:02 | flume studies. They're getting better and using sandboxes, analog studies, |
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| 62:12 | better. We're doing numerical modeling. better and better. This particular type |
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| 62:18 | model is we are trying to reconstruct what this model is basically trying to |
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| 62:31 | mounting services, flow conditions within a pro grading air sequence. Uh This |
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| 62:39 | is from where we can reconstruct wave and even mud fallout based on numerical |
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| 62:52 | . We're using things like the tribal geo chronology. Uh to better understand |
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| 62:58 | needs. Uh We're still using photography other things but this has really made |
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| 63:05 | um much more quantitative in terms of the source areas. We can also |
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| 63:17 | to look at Modern or not modern pleistocene environments in a way that we |
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| 63:24 | before we were limited to carbon Now we can do other ways of |
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| 63:28 | thing, particularly aeolian deposits. So me end with quiz. No |
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| 63:36 | Just so here are a couple of of sedimentary structure and you tell me |
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| 63:43 | that structure would be called? What of sediment destruction is that? |
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| 64:06 | are all the beds parallel? Okay, so we know it's not |
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| 64:12 | plate orbiting. Were they evenly No. So how would you describe |
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| 64:26 | package? Think of this as a fictions? How would you describe |
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| 64:32 | Some of this find great ST blank, fine grain sand fill in |
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| 64:39 | blank blank. Well, the simplest is cross stratified. Save the |
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| 64:54 | But a better answer would be How many have heard term have you |
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| 65:03 | Hamachi? Yeah. Do you remember it first? I'm sorry. |
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| 65:14 | don't give me this. Okay. many cost the strategy for a Hummer |
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| 65:24 | in the middle. And and it's to reflect deposition, low wave base |
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| 65:33 | a rather deposition below fair weather wave by storm waves. Okay, so |
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| 65:38 | is a characteristic of a particular environment form waves. Having said that, |
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| 65:46 | course, usually that means 50 100 m. Having said that you |
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| 65:51 | find little ones like this on the parts of macro title. Open marine |
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| 66:00 | flights. Yes, we got to a little careful about attributing genesis to |
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| 66:08 | is descriptive. How about this? would you call that? Ross |
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| 66:20 | Okay, that's a good start. . What kind of Australian? I |
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| 66:44 | hurt. Seven Is formed by three . You do. Okay. |
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| 67:05 | the flow maybe kind of obliquely towards or away from us. Yeah. |
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| 67:17 | what do you think was the Give me a genetic interpretation of this |
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| 67:22 | . Cross stratified, let's say horse since public sandstone. Yeah, sure |
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| 67:37 | . That's that's a good possibility. point. Oh, and in |
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| 67:45 | this used to be called, which one of the problems of mixing genetic |
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| 67:54 | objective interpretations or descriptions. The problem , is that mean fossils here? |
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| 68:03 | . So this is in Uh, know, I'm gonna turn that one |
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| 68:16 | , but how would you describe this of failure? I give it to |
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| 68:23 | blood stone stand still. Internal inter . Okay. It's but so there's |
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| 68:37 | special order for style, anybody remember ? Uh, not here. Look |
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| 68:56 | the scale. Here's a pin So whatever is occurring here is on |
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| 69:04 | order millimeters. And that's one point you're interpreting alcohol. Think scale. |
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| 69:18 | , it's it's called mixed bedding. . And mixed betting, uh, |
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| 69:25 | characteristic one of the characteristics of intertidal intertidal losses. This is ripple |
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| 69:35 | well, SAm. Okay. And my first thought would be, |
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| 69:42 | this is probably the intertidal deposit were for the fact that right next to |
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| 69:47 | is a big submarine channel. So we're looking at is a let me |
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| 69:54 | on a submarine channel system. So turns out that the processes of |
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| 70:05 | mud, sand but sand and an title deposit are somewhat similar to the |
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| 70:13 | of candy pelagic mud. Overflow sand a turbidity con in reworked as |
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| 70:24 | Okay, what about this? I'll tell you its cost ratified. What |
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| 70:29 | you think would be the environment of ? Use this person for scale. |
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| 70:43 | would you find foster this? Is ? Well, what kind of environment |
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| 70:59 | deposition gonna be a tidal flat? , the problem is you have to |
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| 71:17 | a bed for it's migrated right That's where can you get a |
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| 71:30 | I am first best eight m high this church. Well, one thing |
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| 71:49 | be a sandu sand dunes did Who do you think this was deposited |
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| 71:55 | sanding? It could have been part our center. Check your head. |
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| 72:04 | , why not? Well, part it is because I know that this |
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| 72:09 | been here. I know the sand transport tells I also know that this |
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| 72:15 | here is full of sand dollars. this is a marine setting. So |
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| 72:23 | turns out that in then if we a little more closely see light and |
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| 72:30 | packages here. Those are tightly influenced surfaces. So this is a title |
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| 72:43 | on a tie dominated shelf. But know that we need to know something |
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| 72:50 | the texture, the hypno fossils and of the forces. Okay, |
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| 73:01 | here is a set boundary here are best. So I guess the first |
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| 73:10 | is what direction would you infer the of water or when I'll give you |
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| 73:18 | clue it's gravel, so it's not be wind right to left or left |
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| 73:25 | right now. Over here, we that the forceps were dipping in the |
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| 73:42 | of flow. This Large Ridge was on top of this one. Following |
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| 73:51 | rationale, what direction do you think water is moving? It looks like |
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| 74:03 | going in. It looks like these . Uh The only problem is that |
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| 74:15 | blowing from left to right, which we have to infer a large bit |
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| 74:28 | where the sediment is migrating up ST sorry. Up floor. Can you |
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| 74:34 | of any bed form that migrates up ? Is is any of this? |
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| 74:55 | I break Never heard of the anti you? Yeah. Um So what's |
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| 75:12 | Okay, well it is a headphone migrates upstream. We'll talk about that |
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| 75:24 | . Okay. Oh and and the here is this is in a submarine |
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| 75:30 | system or channel system and these are , basically turbidity currents that are forming |
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| 75:42 | bed forms that are creating upstream. the way, The sand is still |
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| 75:49 | downstream. It's just eroding on one and the positive backside. Okay, |
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| 75:57 | let's end this reporting by just kind a summary of where we're going. |
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| 76:03 | for you don't want to go against so we're gonna go through sediment supply |
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| 76:13 | fluid flow of transport that forms in structures and then we'll go I'll tell |
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| 76:24 | right now I don't think we're gonna past because for the exam it's |
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| 76:31 | Always overly optimistic and always take longer so the next friday. I'm next |
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| 76:41 | A week from tomorrow at 8:00'clock Exam will include whatever I haven't finished. |
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| 76:47 | example one may 4th part three. also show system exam and here's a |
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| 77:04 | of all of your exams are on , is that right? Okay. |
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| 77:14 | This has been Wednesday night um for fine. I'm gonna call the |
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| 77:19 | let's focus more on material from the last part of the course but we |
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| 77:28 | on things and I will actually in cases on the study guide to compare |
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| 77:33 | from earlier topics. Um It's about gonna give you about two hours and |
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| 77:40 | question to you is would you rather at six or so? I'm not |
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| 77:48 | where you're coming from. Mhm. what's traffic on six. What about |
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| 78:02 | ? Okay well this ship seven and different. Okay let's stop recording and |
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| 78:11 | about a 2:30 but about a 15 break and we'll start on topic to |
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| 78:24 | . Okay let me uh crazy. I do want you to stop the |
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