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GEOL6351-Basin Modeling - Day5 10-07-2022
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00:05 Hey bos let's give you a There he is to check in.
00:09 , how are you doing? Doing , thank you. How are
00:14 Good, too bad. That we see each other in person this
00:19 but this is this is good as . Do your talking but we don't
00:31 you. Ah Does it work Yes. It had to update my
00:50 for some reason, but but I but I was laughing. I
00:54 yes, man, that's Mhm. . So, no, it's
01:02 Um So we're a minute early but we get started? We have so
01:08 material that we need to go So go um that um um that
01:17 hope that after this weekend you'll be to um name all types of rift
01:24 , explain how they form and where form. And then also say something
01:30 um you know, static graffiti. the sediment inputs and heat in those
01:37 . So, factors that can affect petroleum system. Right? So,
01:46 started. All right, you can this, correct the slides,
01:53 So, we're gonna start very left last week weekend. So, this
01:58 with these um continental rifts odes. , can one of you describe characteristics
02:06 a continental rift. So, it's upper figure here. What would you
02:11 if I would ask you describe an continental rift? The heat beneath the
02:20 is actually pushing it to escape That's the reason the plates over the
02:27 are drifting apart and there's a border which is formed between them and if
02:34 force is much stronger than the rift be much wider and the plate between
02:40 crust and the ionosphere gets thinner, ? So a few things that I
02:48 to add. So what's happening and you see that here in the
02:53 figure. Let me see if I show it to you. So the
02:57 stretched right here stretched and that's why thinks so because it is stretched it
03:04 . And that leaves space to come mental and industry to come up from
03:09 to fill up that space basically. you name some characteristics of the rift
03:17 ? So, if you would be over the surface of the earth and
03:21 would see a continental rift zone what, how would you describe
03:26 What would you see at the surface the earth? Hmm. So you're
03:41 happy geologist walking around in a rift and you see, what do you
03:49 depression in the earth mainly. So maybe something like a a topographic
03:58 . Right. Um, that is in with sediment and yeah, that's
04:04 good start. Okay, um, , because this is a low point
04:16 the landscape, it would be a place for a river to flow or
04:21 a lake to form. You see in the east african rift, for
04:26 , what else? So, you can see it in the uh,
04:29 here here volcanic activity, correct? . So today we're going to talk
04:48 what causes that volcanic activity. But , that's what you often see.
04:52 that may be going on today, it may also be something that went
04:55 a million years ago, for Yeah. So you see a basin
05:00 has been filled up with sediments. you see volcanoes or volcanoes or active
05:06 because this is a low point in landscape. This may be a place
05:11 a river could be flowing or lakes formed furthermore. You can see that
05:17 the upper figure very nicely here. may see groups. Well,
05:25 you know why it's not doing Sorry. My family is just not
05:35 too well. I hope it comes in a little bit, but you
05:38 sketched in the cursed in the upper the city's falls. Right, Normal
05:44 . So these normal faults are characteristic rift zones as well. Okay,
05:50 , let's take a look at the most panel, the the rift margin
05:57 the rift ID ocean basin. So , how would you correct rise drifted
06:03 . So you want to see right. It's the continent buried below
06:08 or below the sea. What does look like? Well, you have
06:22 marine environment with the mid ocean ridge the middle. Um, and volcanic
06:29 . And what do these merchants look ? So the rift that march in
06:32 edge of the continent, if you have to describe it, what it
06:36 like below the surface. what what you say they're following some layers kind
06:44 thing towards the surface, it's like or? Yeah, I think it's
06:50 building up into the layers obviously curves this, correct? So what these
06:56 consists of their settlements, right, packages that are present on the edges
07:01 the continents. Absolutely. And um else do you see in the
07:11 I think that these figures, I they are beautiful but they're I think
07:20 but they don't clarify is that you're just producing new oceanic crust. You
07:26 produce new oceanic lift this fear and , it doesn't really show that
07:33 And you know, you know what mean? I mean, this is
07:36 is it. This is the top is defamation of existing crust and continental
07:44 a sphere. But once you start ocean floor it's still a rift.
07:49 now it's it's an oceanic rift that's a result of brand new. You
07:55 , the creation of brand new little and crust, it doesn't really show
08:01 in the bottom. So I just I'd complain a little bit.
08:05 that's fine. So let's talk about bottom figure. So in this bottom
08:11 , where where are the sedimentary Where would you look for oil?
08:29 you. Maybe um just outside of mid ocean ridge or along the shelf
08:40 of, can you see my Right? Yeah. So this is
08:46 they form, Right? So at edges of the continents here in the
08:50 ocean basin, that's not really where looking, we're looking in this region
08:56 . So where you have a lot sediments that were deposited here, You
09:01 , there's these old rift zones right. The sediments came from the
09:05 , they transported them here um on of those sediments or in between we
09:11 marine sediments that were formed in the basins. So these are the regions
09:17 we are looking for petroleum really at edges of the continents. So,
09:22 you think about the gulf of Mexico example, um um the, you
09:30 , the platforms where the production they're fairly close to the continent.
09:37 they're not in the center of that , but they're they're surrounding, basically
09:43 the continents. So that is this here that we're looking at.
09:54 Questions about this. All right, on. So then we talked about
10:04 figure, right. Which is not . I'll show you a more realistic
10:08 later, but it shows some, know, zoom in of such a
10:13 . Merchant. So, you see , a lot of sediments here,
10:18 sediment packages some of them in source you see normal faulting. So maybe
10:24 are other rift basins present towards the here. You can see the oceanic
10:30 , oceanic mental atmosphere and it's this here basically what we call the
10:37 And maybe in this area here where would go to look for um
10:44 So the shelf is very shallow So it may be 100 m layer
10:50 water or maybe 200 m, but more than that. So that isn't
10:54 , you know, an easier place drill. And then here in the
10:59 ocean basin, you may be looking kilometers of water before you reach the
11:05 of the sea. So if you here, you first need to
11:12 you know, the bottom of the basin right before drilling can start and
11:16 you may still have to drill a kilometers steps in order to reach a
11:21 on the shelf. We have a thinner layer of water, maybe only
11:25 m 150 m before you're at the bottom and the drilling can start.
11:31 you can imagine that being on the is logistically easier and therefore cheaper and
11:38 . So that's where we prefer to questions about this. No man.
11:48 , let me move forward. So we started to talk about continental rift
11:52 . And so again, you start with a continental rift basin and some
11:57 them may develop into drifted margins after breakup. Oftentimes there is no continental
12:05 , we're just left with a continental basin. So here is one
12:09 this is the new ground rift zone colorado and new Mexico and here you
12:16 see you know what, it's very for these first places, Their elongated
12:21 there long maybe 1000 kilometers long and not very white, maybe 50 to
12:27 or 200 kilometers wide. And that's . So this is very very typical
12:33 the right map. We looked at earlier and you see that these spaces
12:38 founded by normal faults and within these faults, you can find these
12:44 We also saw that they are not not like one elongated fault or one
12:52 rift basin but just broken up in in shorter segments. So that is
12:59 structure you would find um on the of margin. Alright, I'm gonna
13:07 this because we talked about this. also talked about this a little
13:11 So why is this the case? if you start to stretch a continent
13:16 stretch the crew's, what's gonna happen you're gonna first form the short
13:21 You can see that those in the panel here, some of them are
13:25 perpendicular to the extension direction. So make perfect sense where they were
13:31 Other ones have an orientation that is favorable. So on the in the
13:36 of time when you go down these , you see that the ones that
13:40 more favorably oriented, they will start connect. They lengthen and then they
13:46 these border falls. These falls bordering rift zones. All right. We
13:55 talked about why these restaurants offer typical , I'm not gonna ask you this
13:59 the exam but it has to do these faults that form right? They
14:04 across the brittle crust and that the of this brittle crust and basically determines
14:10 length of these faults and how wide respiration is. So that is why
14:16 earth they all have this typical um know the typical lengths and the typical
14:22 basically they also have a typical depths that is again controlled by these
14:27 Right? The steepness of the the thickness of that ritual layer.
14:32 that is why these first basis look way they do on earth. No
14:38 question for you is where do the come from? That fill up these
14:43 basins that we find in on the . The mountains are the river
14:53 correct from the surrounding mountains, they by streams, They may be broadened
14:59 landslides, rivers flowing through the rift and the transport and the positive
15:04 Excellent. So these settlements, are typically high in organic carbon or maybe
15:17 ? Probably not correct, probably Um Unless there will be a swamp
15:24 So you know, if you think these mountains, they are eroding the
15:29 are transported down. There's probably not lot of vegetation that is going to
15:34 part of that story. And also you form a lake or maybe a
15:39 area, you're not going to be this up with a lot of organic
15:44 . So these sentiments by themselves would be good source rock, A good
15:49 rock has a high percentage of organic , Right? Um however, if
15:55 form a lake in such a rift , you can imagine that you would
16:00 lake sediments that are more organic So, um those types of settlements
16:09 become good source rocks. Number of for you. How thick are the
16:16 packages in such rift zones? What we talking about here? Do you
16:20 that? I did not. How you, magnum. How much thickness
16:30 they found? How sick early settlement that we find in these rift
16:40 kilometers um you know, such rich against 50 kilometers 100 kilometers wide.
16:46 the sediment package can easily be a kilometers to 67 kilometers thick.
16:53 it's a pretty big basins questions. right, did we say? What
17:01 the depth? Yes. So, has to do again. It's of
17:05 the amount of stretching right in the more you stretch bigger becomes the
17:10 and deeper. And then it also to do with, you know,
17:14 normal faults they form in the And um let me go back a
17:20 figures here, you can see it the left. Um So here,
17:26 can see an animal fault that cuts the cursed. So, you can
17:34 that if you're brittle upper crust is and you have more extension and steeper
17:39 then you can form a deeper rift . So there's a relation there with
17:45 know what we call the Realogy of crystal, The crystal layer in the
17:50 , the thickness of the brittle The terms the thickness of that settlement
17:56 general. Again, the more you , the more accommodation space she creates
18:03 general. So a rift basin that just starting to form maybe a million
18:09 old, will probably be shallower than that has been forming for 2030 million
18:16 . Good, good question. so we talked about this,
18:21 this is something we need to So what is the stretching factor of
18:26 rift basin? So it has a initial thickness of the first over the
18:31 thickness of the crust. We also about what normal values are for a
18:37 rift zone. What what was the value? It was like 1.3 or
18:44 . Yeah, something like that. if you would see a number like
18:49 , that would look like a normal zone for trump of the rio grande
18:53 or the North sea rift or the African rift. Excellent. And then
18:59 large stretching factor. What's going So if the stretching factor is four
19:04 six or maybe 10, what are looking at? Just have a
19:15 Alright, you've stretched more so your base is probably bad, developed
19:20 deeper And at one point in time go or we can go to continental
19:26 . Okay, right, so this hopefully you remember um continental rift zone
19:35 stretching factor of something like 1.21 point filled with so many restaurants on
19:44 They do not stretch or later wanting break up, but they feel at
19:48 point in time and then below the you can see a um that's one
19:54 in questions about this figure. You what? Okay, we also talked
20:08 this stretching model. So this was first one that was being developed to
20:13 continental rift zones. Right? So is a paper that you have which
20:17 you the background information if you're interested . So, this person described
20:22 if you, you know, stretch atmosphere, what's gonna happen? You're
20:25 send the crust, you're gonna send mental atmosphere and you gonna introduce heat
20:30 the system that's really nicely described in paper. So, if you haven't
20:35 it yet, I would take a at it. So it's called,
20:40 can see 1978. So what does model meaning? What does it
20:47 So it describes the formation of continental zone. So, in this
20:52 the little sphere, so the crew's layers are stretched instantaneously. So very
20:57 . Benefactor of data and and thinking the little sphere with the fact of
21:02 results in aesthetic subsidence. I'm gonna back to that in a second.
21:10 subsidence occurs very slowly cause so that gives you the typical subsidence curve of
21:17 continental rift zone or drifted margin. you have rapid subsidence when you have
21:22 full thing going on, the formation the continental rift zone. And that
21:27 followed by slower subsidence as this rift some slowly cools off. So at
21:34 point of continental breakup, which would around here, your rift basin will
21:40 to cool or maybe your rift starts fail at this point in time it
21:48 longer is actually extended and then it start cooling down as well. So
21:56 on the horizontal axis of this What should I write there?
22:12 vertical axis. So let's fill in access. If we're looking here at
22:23 continental rift zone, any idea how million years we're talking about here?
22:34 cents of millions of years. So this could be, you
22:39 10 2030, 40, 50, , etc. How about this vertical
22:49 ? How what is the scale Maybe in kilometers? Mm I don't
23:01 don't remember. Take some 10, luckily it's not that bad. It's
23:12 a few so 1234 kilometers. So that's right subsided stretching, but that's
23:30 , now let's practice also a lot for the coming weeks. Um
23:38 I'm gonna give you turn to practices you would have to describe this
23:43 So this curve here, how would describe this? So, this is
23:48 typical subsiding curve of a continental rift or lifted margin. Why is it
23:54 fast and then slower? Nothing to . I would say there's rapid subsidence
24:00 because of the Magna magna bloom. then over time that's starting to cool
24:09 slowing down the subsidence, yep, great. So let's take a look
24:15 the first part. Why is there rapid subsides here mechanism? You
24:23 it's because the heat from the magma pushing out and even the force between
24:31 plates are more so it's actually drifting and the crust than the its thickness
24:38 reduced. No. So that's why asking both of you. So,
24:43 me go back, right, We're go back to this first figure
24:53 this one here. So, that's part of the curve. This
25:01 that's this phase. The slower part the curve this part here is this
25:09 and that face. So why is steep? It's because we are when
25:19 when we're in that stretching face, , for these these normal falls,
25:24 are rapidly subside you rapidly from the rapidly subsided. So at this point
25:30 time it has nothing to do with heat yet. Right. That cooling
25:34 gonna come in here. So it's just purely the effect of stretching
25:38 thinning of the crust thinning by normal sending by dr information in the lower
25:44 that causes you that very steep initials science. So it's literally these
25:58 the geologic processes that you're looking at cause that's very rapid sub science.
26:06 I interrupt? So I think of as the first part as being structural
26:16 , basically busting up the crust and it to form the rift um at
26:22 top like you say. And I of the other part as being thermal
26:32 that's exactly what it is. So part is related to this phase.
26:38 you start to stretch the crust and you break up the crust with normal
26:43 within the crust. So I think word mechanical is is a very,
26:48 know, structural mechanical. That's a good description of what's going on and
26:52 breaking the crust. All this has do with cooling. It is cooling
26:59 the stretching effort got reduced. At one point in time it stops
27:04 , It stops at the point of breakup. So here, what you
27:09 when this happens continental breakup, you a spreading ridge here and this and
27:16 just becomes passive. It doesn't do anymore. It sits there, it's
27:20 longer being stretched. It's cools I think that what might be confusing
27:33 this diagram is you see the the plume under all three of these but
27:39 the early phases, the mechanical substance due to the mechanical busting, breaking
27:45 stretching the crust. It is much than the heat effect. The heat
27:51 um dominates later or whatever. I that that it's kind of confusing when
27:57 look at that, it's possible. what this indicates here is basically um
28:08 so this is not a plume. this is basically the filling in of
28:17 , in the earth, there's no , right? So if you switch
28:20 that's in something, something is going fill in the space. In this
28:24 case, it's a stem, a . So it's not really a plume
28:31 in that war, if you know I mean. That's that's not what
28:35 trying to indicate here, even though looks like it. I agree with
28:44 that then. It looks like Okay. Yeah, that makes
28:50 That's kind of how it was visualizing . Um maybe throwing me off a
28:55 bit. Yeah, I see now it can be confusing. Is this
29:03 to you, 99? Yes. I think I understand why that's not
29:10 it upwards or something like, Yeah. So what happened? It's
29:16 arrows, right, This is what's . You stretch it, you've seen
29:20 and as a result of that stuff up. That's how you should should
29:24 it now and then. Which you here, for example, the last
29:29 . So these plates are still pulled but the stretching now no longer occurs
29:34 or here. It occurs here at mid ocean spreading center. Okay,
29:41 at this moment, it's just hanging . It's there. But it's no
29:45 actively stretched and thinned. I'm Did you say it stretches at the
29:56 ocean ridge? So here and when you do these plates further apart
30:04 these margins, these were spaces. will not continue to stretch their too
30:09 . This is not where you work a stretching thin. Where if you
30:14 these two plates apart, this is be filled up here at the spreading
30:20 . So the spreading center is where will make new ocean cursed your
30:25 Oceanic mental little sphere. This is place, Yeah. I mean,
30:32 don't know, you can correct but to me, I mean,
30:35 you start producing oceanic atmosphere, there's more rifting because any extension, any
30:44 of the place is accommodated by accretion new sea sea floor, new oceanic
30:51 . So, so that's the reason no longer anything is happening like here
30:57 here. At that point in the new activity is going to be
31:03 , if that makes sense. So is why we can say that at
31:13 point in time. Near the center this point in time, you are
31:17 in the cooling, you see that no more stretching. It's just not
31:21 happen. No more stretching for a here or a point here, all
31:28 , you know that divergent plate motion gonna happen here at the mid ocean
31:34 center. So it's no longer going stretch further here or here. It's
31:38 gonna happen in the center. Makes , or? No? Yes,
31:55 follow you. Right, sorry about . This was confusing. You
32:01 I think I'm doing a good same ? By selecting these figures, but
32:07 I realize that they also introduced So, I'm sorry about that.
32:16 job of explaining. Thank you. , So let me see what's
32:20 Okay, this is what we were about, right? So if you
32:25 such a typical silence curve for a zone, if this fast phase before
32:31 breakup and then the thermal cooling phase breakup. So before continental breakup,
32:38 actively stretch your riff base and you make it wider and deeper. There's
32:43 faulting. That's why you have that subsidence mission. So, I think
32:48 way those explaining, you know, it tectonic or structural or mechanical,
32:54 makes sense. Right. Alright. about this. So cooling only happens
33:06 continental breakup. Yeah. Or if rift somehow has died. Well,
33:12 , that's what I was getting So it's possible for a continental rift
33:16 to just stop drifting but not reach breakup. Yeah, it just happens
33:23 times in the geologic history to the States has several examples, those rifts
33:30 you may have heard of the mid rifts, which extends literally from central
33:37 us to, you know, almost south and I think I have a
33:42 of it later on, um you , we have these these old rift
33:48 that never did anything anymore on all in europe, you have, for
33:53 , the North sea grab. And may have heard of that in the
33:56 Sea, it drifted for 100 million and that was it. And then
34:01 died out. And I was just there. So we see it everywhere
34:04 Earth. So sometimes you break sometimes you don't cooling. Also,
34:11 might be a chance that the rifting after some age, right or
34:18 Which is stated again. I don't I understood what you were asking.
34:23 after it gets cool. Also, there any chances that it might drift
34:28 and the forces might start? that may also happen. Always happen
34:33 these tectonic plates they move around, ? So you never know what's gonna
34:37 200 million years from now. You , the continent may become on the
34:42 again and it may start to rift . Yeah, good point.
34:48 Right. I'm not gonna go to little bit more work on the board
34:56 we go back to the power So, let me talk about this
35:01 and it's called and remember we talked it earlier as well. So the
35:10 example, I'm going to show you what happens when we send the
35:14 we did that last week as I'm gonna do it again. But
35:17 I'm gonna put numbers down to ice columns. Okay, so towards the
35:35 I've sketched a column with a crystal that's seen its 35 km thick and
35:41 mental industry layer. Ml that is kilometers thick. So in total the
35:46 sphere here is 100 kilometers stick. , who knew the density of the
35:54 material, right row ecos. Do remember what a good value is?
36:10 , 28:00 And the density of the ministry we talked about was about 3300
36:24 per team. What we're gonna do you're gonna rift this. So that's
36:37 be extension and after extension, we have a pretty good idea what our
36:48 zone look like. I'm gonna sketch towards the rights so we riffed it
36:54 then we end up with a layer water maybe lake above the rift zone
37:03 it. We have a thin crystal that is not 20 kilometers thick.
37:09 here's the crust again underneath it, have a layer of mental atmosphere.
37:17 say it didn't seem, let's say since the cursed and underneath the mental
37:24 , as you know, we have esteem a sphere correct and say That
37:42 since the cursed is 15 km. now in this column We have like
37:49 km, 15 km of esteem a . No, In the case of
38:00 to see what they're going to assure is the case on Earth. We
38:03 say that these two columns weigh the . So the density of water,
38:09 gonna say it's 1000 kg per The course is again 2800. Mental
38:16 again. 3300 and esteem a sphere a density of 3200 kg per
38:26 So the esteemed density is lower than of the mental atmosphere. Now with
38:32 to see, we saw before what do is we make the weight of
38:38 columns equal so towards the left, have 35 kilometers times the density of
38:45 hundreds Loose, km times the density , equals the right side, the
38:57 side, we have a water Times the density of 1000s plus 20
39:06 of crushed, times the density of Plus 65 km of Mental legis
39:17 sorry, Dere of 30 300. 15 km of atmosphere, transit density
39:29 30 200. So, we have an equation that many factors filled
39:39 And the only thing we haven't filled is this water laying. But if
39:45 would fill this in and switch these around you would end up with a
39:50 layer that is about three km So three kilometer deep water layer.
40:09 in other words, if we have little sphere that we're extending and for
40:15 reason we see in the cruise, we don't see the mental little
40:20 we form a, you know, the surface of the earth is going
40:24 go down and reform a basin. basin can be filled up with
40:31 This is going to be important for a few minutes. So keep this
40:36 mind. Makes sense. Right, questions about this? No ma'am,
40:43 , now we're gonna move on. when I do the same, but
40:49 of thinking chris, we're gonna sing mental legis fear. So we start
40:54 with a column here with chris and legis fear This is 35 km
41:02 This is 65 km thick. And what I'm gonna do towards the rights
41:09 sketch and all web column, we the first 35 kilometers. The sentimental
41:18 sphere made me send it to 40 underneath it. We have esteem a
41:27 rights and we can see, You , 25 km singing of the mental
41:37 is now filled up with steam sphere . So we have about 25 km
41:43 esteem a sphere and then what's going here, there's something going on,
41:53 know, maybe there's again a water that that forms or maybe something else
42:00 , let me just call this Because we don't know what's going on
42:07 I'm gonna give it the density of , but for this story uh
42:13 but for this story it doesn't really much. Now let's apply the principle
42:19 course, to see again. And the left side should weigh the same
42:23 the right side. So it's 35 2800 65 times 3300 equals on the
42:34 side, 35 times 2800. There's km new mental atmosphere times 3300 Plus
42:47 a steaming sphere layer, 25 km times the density of 3200 plus,
42:53 x layer or whatever it is. let's fill it with water. But
42:57 doesn't really matter for the story. we calculate all this, we get
43:04 X. That is a plus second . In other words, the free
43:20 a column of Earth. We're gonna a mental it was fear, but
43:25 across that column is gonna go Yes, gonna uplift, it's gonna
43:35 up. And that is in contrast what we just saw, What we
43:40 saw is if you have a column little sphere and it's in the
43:45 you're gonna get subsidence of water There was actually a minus sign
43:50 If you calculated that. It didn't tell you earlier. If you see
43:55 the Mental Little Street, but not crust where you see the mental industry
43:58 than the cursed you go like that list. No, you may wonder
44:04 do we care? This is right McKenzie says, we have crystal
44:10 where we have as much crystal. little christening the root of that would
44:17 be that you form a basin sedimentary , you have subsided to form a
44:22 . That's Mackenzie. But we'll see . So they'll actually commented on this
44:30 last week. Is that um their on some birth where you where there's
44:38 where you think the crystal out but the mental atmosphere and other places where
44:41 is in the mental atmosphere a but not the christ and then instead
44:47 from the basin you have uplift. keep this in mind. I'm just
44:53 go back quickly to see if we intuitively understand this. So what we
45:00 to look at them are the densities these layers. So here, yet
45:04 cursed. Yeah, you have to religious fear. And here you have
45:13 austere atmosphere. The city was then that he was 3300. Then
45:24 he was 30 200. Right. one, we send the crystal layer
45:33 we say that that material in that at the bottom is filled up with
45:38 steam sphere. So chris sent and fear wells up to fill that
45:47 We saw that this scenario results in . Can you think about why that
45:58 be the case without doing the So we remove layer, of course
46:03 keep the mental atmosphere the same. basically adds a layer of the atmosphere
46:07 our column. If we're looking about steps, why would this column go
46:17 , Let's call him this cologne. in the cruise. But not a
46:24 atmosphere. We have sub science. is it? Well, because you're
46:32 thinning the crust within a certain amount area. Um So at some
46:38 you know, the crust isn't being by what's going on there. Um
46:43 the crust is staying on the edges that same, you know?
46:50 I don't know if I'm explaining that well. I know I'm not but
46:53 , I think you're on the right right track. So if you send
46:57 crust so you remove they of course not this thing. If this is
47:08 I use a static compensation depth and say the rate of a colon of
47:14 . This death is always the When you when you when you send
47:20 crust, you basically replace that lower crystal material. It's a higher density
47:27 fear in the same column. And a result of that, your column
47:32 goes down. There's gonna be more gonna add math. Two words Re
47:38 scenario too. If you keep the thickness to sing, which is in
47:47 mental little sphere. So maybe the little sphere Now is this thing after
47:54 extension. This this here this space going to be filled up now with
48:00 lower density atmosphere. Lower density You can fit more into a problem
48:07 lower density and higher density. So will go on. Makes sense or
48:21 . Um I'm kind of having a time following. Right. Um Let
48:28 think how else I can explain I'm just gonna try again the
48:35 Yes. This here is a compensation somewhere in the S. T.
48:41 fear and we say that the weight the Columbia above should always be the
48:51 . This case we had a first little sphere and a steam a sphere
48:58 um send a mental atmosphere. So line goes and now we have a
49:07 mental atmosphere above this compensation that's We still have that column and now
49:15 have added lower density estamos fear where used to be higher density mental atmosphere
49:24 the atmosphere has a lower density than mental atmosphere. So there used to
49:28 high density material and replaced it with density material as a result of
49:35 This goes up the situation towards the we had a cursed a mental
49:44 Oops, let's make this sticker a little sphere and an esteem a
49:52 What we're gonna do on the we call a cinder crust. So
49:56 layer becomes thinner. This mental little layer, we didn't change the sickness
50:06 it moves up and we have more a sphere in our column. This
50:14 a density of 3300. This has density of 3200. This is the
50:20 of 2800 in this particular case, column torched the rights we basically replaced
50:27 density, cursed with higher density, schema sphere. And as a
50:34 this goes down, we get subsidence or not. Yes, ma'am.
50:41 you. What about you, Why does the density of the atmosphere
50:47 less than the mind, Bill. an excellent question. Does anybody know
50:52 answer? That's really an excellent McKenna. And that's it's keen to
50:57 this because it's hotter. Maybe It's harder. And as a result
51:08 that, it's actually more some it's exactly the cases because of
51:14 It's hotter. It's hotter and therefore a slower density. Yeah,
51:20 Right. For now I'm gonna move and we get back to this later
51:24 hopefully it becomes more clear than how gonna apply this. So, we
51:30 about this last time, right? called Mackenzie's uniform stretching model. This
51:35 not as in petrol moat. And on mode and all those softer benches
51:40 as we saw last week deal wasn't with it and neither is anybody
51:45 But unfortunately, this is what it . So, um, what we
51:52 is that, you know, within crust, within the mental little scary
51:57 . So after stretching, you end with a little sphere that's much
52:01 It's in a crust as in a sphere. And then here on top
52:05 form a basin, right? Which a rift basin. And after a
52:13 period of time, maybe we're in process margin after breakup or the task
52:19 down. We see that the whole whole system cools and eventually the mental
52:27 sickens again. Now, first question you, why was this the
52:35 Why did this happen after a long ? You remembered it? You have
52:46 do with the term right to the of the little sphere was an ISIS
52:55 , right? Most people say it's surgeon all degrees Celsius, but we
52:58 really know something like that. And if you screw the whole system
53:03 this base is gonna go down because cool the system down, that ISIS
53:09 gonna go deeper. Yeah, Not a question that I have for
53:17 , I'm just gonna go forwards and backwards again. Right? So if
53:23 gonna sketch vertical axis, heat flow the basin, the horizontal axis is
53:40 and I have rifting between this point time and this point in time.
53:46 the heat flow that goes into the in the beginning. This is my
53:51 face, what is gonna happen at heat flow in the basin? During
53:56 , it's gonna increase. We don't what it looks like. Maybe something
54:01 this. Right? Makes sense. is going to happen at this point
54:06 time. So at this point in , rifting has stopped either because there
54:10 content to break up or maybe the based and died out. But drifting
54:15 stopped. What's gonna happen with the going into the basin just start
54:20 Yeah. So maybe something like this now, the second situation,
54:31 we're looking at a different pace and different rift basin in the same amount
54:36 time between this point and time at point in time is gonna rift twice
54:41 much. What do you think is happen with the heat and put into
54:45 basin? So, the second example , same, same, same,
54:50 know, same conditions. But the now is gonna risk twice as much
54:55 the same amount of time. What's to happen doing creams? Yeah,
55:03 gonna have higher heat. So, just gonna sketch it here.
55:07 this is the same, right? if you rift much more, you
55:11 much much more. You think the much more in the mental it's very
55:14 more you bring much more heat into system. So maybe it's going to
55:18 something like that. You see that it's gonna go down again questions about
55:29 . All right, let's move Tim talks about these subsidence histories and
55:38 see here, risotto exercise time we have stretching of the little sphere
55:46 it's a zero and what's the We have time since end of
55:50 So that could be time since continental over time, since the rift basin
55:55 stretching and basically died out now during . You have rapid subsidence, you
56:02 that here and then later on is subsidence, which is much slower.
56:07 . That towards the right of this , what you see here are four
56:12 grooves, some stretching factors that are , so much stretching factors that are
56:18 . Which one of these groups is highest stretching factor matter? The lowest
56:27 . Do you agree? Mackenna? lowest one as well? So which
56:38 of these four curves has the highest factor. The post tour, I
56:49 the one which is prominently black, this room. Okay, great.
56:58 is that just because the vertical Is that correct? So what you're
57:22 saying is the more you stretch, more you think, the more you
57:28 . So that's why the deepest subsided to most stretching, correct?
57:36 ma'am. Do you agree McConnell? , perfect. Ready. Um it's
57:53 one you want to go through this here. So, Mackenzie stretching model
58:01 to great annoyance of many people is simple. Right? You know,
58:05 came up with this model first, now we know there were of course
58:09 much more complex than something that you stretch and thin. So one simplification
58:15 that Mackenzie stretching model, is that is uniform with that And with that
58:20 mean, is that there is a where the cursed is stretched to the
58:24 bed better equals to the mental little is also stretched with a factor too
58:31 we say that that is called delta would be the mental little sphere stretching
58:36 in data. The crystal stretcher factor this case. So if we look
58:42 the continental rift zones, we see often not the case. So deal
58:45 up last time. You know, have a space problem, right?
58:49 going to extend the mental, it so much thicker to begin with.
58:53 how do you get rid of So, we see in practice Byetta
58:58 not equal delta everywhere. It's just is not that simple. So,
59:05 thing that we often think is that you look at the side more towards
59:09 side of a rift zone. So like here and here you see that
59:17 the mental little sphere, that's the gray area here is stretched over a
59:24 wider area than the crystal crystal stretching ends somewhere like here. Right,
59:31 is where the cursed is stretched and stretching you can see is much broader
59:38 . What is the consequence of So here and here we are in
59:44 situation where we do not seem request we do sing the mental atmosphere and
59:50 what we just talked about. If send a mental atmosphere but not a
59:56 , you're gonna go up. You replace high density mental atmosphere with lower
60:03 Testino sphere and that is exactly what's on here and here. So
60:09 there used to be high density mental . Now there is low density a
60:15 atmosphere and as a result of we see uplift of the surface of
60:24 earth. You see that it's a bit uplifted here and a little bit
60:29 here. We see that it's very of us to see that um you
60:37 , incontinent rift zone. So, you look at the Rio grande,
60:40 example, you see very nicely this space in here. But when you
60:45 towards the sides of it, that surface of the earth shows this like
60:50 is a little bit of uplift and see it clearly from the air,
60:55 example, from an airplane, you clearly see that. So that is
60:59 super spectacular. Maybe this is something a kilometer of uplift or so,
61:04 maybe a few kilometers, so it's , you know, it's not
61:08 but you do see that at the of the earth. So, if
61:11 sketch a, you know, as would sketch the topography through a rift
61:18 serves of the earth, this would outside of the rift. Now you
61:21 towards the side of the rift there's a steep drop. Now you're
61:25 the rift zone, maybe a rift is filled with settles. Now you're
61:28 the other side, um there's a , you know, rift shoulder,
61:33 is the fourth. And then it goes down like that. So
61:37 see this very typical for rift we call this often the rift.
61:47 , because it looks like a you see that. So this is
61:54 something that is really happening. Questions this. Um I do, but
62:05 don't really know what to ask um that when you're replacing the atmosphere with
62:12 ionosphere, you're going to get those that you've just illustrated. But I
62:16 I'm a little confused with the subsidence you do have. Um And you're
62:22 that from the rift, but I um just the order of those
62:28 Excellent question. I'm gonna I'm gonna for you. That's really an
62:33 It's actually in other years, it been an exam question since you're asking
62:38 . Now, I'm probably not gonna , let's take a look at point
62:44 point A is within the rift Point B is like at the side
62:49 ? Where you have um No crystal , but you have some mental little
62:56 thinking, so, let's see if can sketch what subsidence curse would look
63:00 . Let's start at .8, vertical , subsidence or debts .8 Oops is
63:12 , right? Um You know, have rapid subsidence during the rift phase
63:18 you have the moral 14 and tectonics on and then later on you would
63:22 slower subsidence. So that will be B is much more complex. Gonna
63:29 if I can sketch it here. subsidence again on the vertical axis.
63:36 , on the horizontal axis, this 4.b. Um So Point B.
63:43 christian national sins but the mental little is since and so what we saw
63:49 , if the crystals send multi mental you will get a little bit of
63:53 over time. Let's do point point C is complex, it's
64:06 So that is a place that's where have a little bit of crystal
64:12 so it's here. But you have mental industry of sinning than crystal
64:19 So this place can be very complex even though know by heart as I
64:24 know what would happen there. So . So what I can imagine is
64:31 you start Kristin, you may have subsidence but then the effect of that
64:37 mental little sphere ceiling may kick So maybe this place never subsides more
64:43 that and maybe it even comes up . So in other words, that
64:50 story that we talked about that will for here in the rift zone where
64:55 have the rapid subsidence and slow subsidence what happens here and here is much
65:00 complex. Makes sense. Huh? ma'am. Okay questions Right, So
65:13 a lot that comes after this and don't need to know all of it
65:20 let's talk about this one more time then we'll have a break.
65:25 so what I'm showing you here, talked about this last weekend as well
65:29 a further cross section through what we a field drift. So field rift
65:36 a rift that is no longer active that we see, for example,
65:40 the North Sea or you have several the United States and other ones on
65:46 . So it's an old rift It used to be active and now
65:49 died out now when you look at vertical transept, so this year's
65:55 right with vertical excesses steps and horizontal distance in this figure, you see
66:02 , it says rift zone. This , that's that that rift zone that
66:08 forms, it looks a little bit the rio grande rift today, or
66:13 North sea grab and in the um you see the normal folding
66:17 These are normal phones. You see sediments that fill in the basin.
66:22 is our original risk basin. If race patients started to die out,
66:28 started to cool down. And what just saw is if you cool down
66:33 little sphere, your base of the sphere is an isil term will get
66:38 . You increase the density, you the density of your little sphere becomes
66:43 over time. And as a result that, you see that the whole
66:48 is going to subside. When you , that whole thing, you create
66:52 accommodation space that you can then fill with sediments. You see that so
66:59 deep part here, that's the original basin. This here is what you
67:06 after you. You thermally cool down whole system, you create a little
67:11 more accommodation space that is then field sediments. And because we often see
67:19 shape of roof patients and patients are um People gave it a name and
67:25 called the steer's head geometry. So most simple explanation for that is that
67:30 caused by cooling of the little sphere the whole system has cooled down.
67:37 that is actually the first line here it has depth dependent stretching. That
67:42 because the mental little sphere was since over a broader area than the
67:51 No, So it's basically the situation we were sketching here. So you're
67:56 basically here and here, when this going to cool down completely, this
68:03 here is gonna going to subside a bit. Is she? That So
68:14 create that extra accommodation space here. this here looks looks exactly like the
68:24 hands that you see here. But on the other side of the flipped
68:30 mirrors, basically you're reading you're Sorry, can you go back to
68:39 last page? Yeah. Okay, this is all going to cool down
68:47 in density called subsidence. This surface going to subside like that like
68:55 So here, you can recognize one of that steers hand here will be
69:01 other half of the stairs that you that. Okay, so that's always
69:09 a result of the ice a therm , the here, um, so
69:16 becoming it's becoming more dense, That's why the subsidence occurs,
69:24 Basically add literally more way to your . Okay, so it wants to
69:29 . Yeah. Are we ready for break? We can take a few
69:39 break if you want. Sure. . So let me stop sharing and
69:50 , Let's get back. It's now past. How about maybe 8-10
69:56 Break. Sounds good. All so role here. Right?
70:11 So the Mackenzie model for stretching of little sphere and rifting shoes that always
70:22 look like this. So, we like, oops, let me just
70:27 a little bit better. So we this board of folds, maybe a
70:31 shoulder underneath it. Here we have mojo, the base of the crust
70:41 we have um, maybe a country fold, it forms here.
70:49 really several of them, I'm just sketch now a rift zone, that
70:56 Maybe your settlements here, sentence And this is a full block and
71:00 is a four block. So in Mackenzie stretching model, this rift
71:07 It's narrow and we saw that last , what that means, right,
71:13 km To maybe 200 km wide. that's it. So in the real
71:23 rift from the westernmost point to the most points is probably 60 km or
71:30 most faces and maybe 200 km in places. But it's narrow and underneath
71:38 we have the moral right which is base of the crist crist assistant over
71:43 rather narrow area as well on There are also white rift zones.
71:50 white rift zones are, for example basin and range province in the western
71:56 . S. Have you heard of ? The base in the range?
72:04 . Um have you ever been in western U. S. Have you
72:08 to maybe Las Vegas? Yes, Michael. Where have you been in
72:14 western us anywhere? Just get the right from India. I know maybe
72:24 in a plane over the rest in rest and had a chance to go
72:33 . Okay, so if you are the western U. S. And
72:37 can actually see it most nicely if plane flies over the western U.
72:40 . And Nevada. So, Las . Very good example of it.
72:46 you look at down at the landscape , it has a very interesting um
72:53 looks very interesting. It has let me just make a sketch that
72:58 . Um It has like um people call that ranges, but you
73:06 think of them in terms of riches they're sticking out over the landscape and
73:13 don't know if I even can sketch a rich, maybe this is such
73:17 rich. Um so it sticks out the landscape and then here are sediments
73:25 in a basin. And then here's one of those riches. And so
73:31 see, and then here's another basin sediments. So you see when you
73:36 at the landscape, a landscape of and ranges and that's why it's called
73:45 basin and range province of the of United States. So the Las Vegas
73:50 is right in the middle of it what this area is, it's one
73:57 the few areas on earth that is wide rift zone. And if you
74:06 look underneath the surface of this this , you would see that many of
74:12 riches are associated with this wide rift . They're basically what you see at
74:18 surface of the right rift zone. , if you look at this area
74:23 the surface, you don't see the stretching model. So you don't see
74:29 that looks like this, that's not it looks like. You look at
74:33 regions, the subsurface looks more like . Let me see if I sketch
74:41 correctly which is here. So, other words, very asymmetric extension or
74:57 rift, we don't know what the term is. So, the Mackenzie
75:03 model again, when we sketch we sketch it as something that is
75:07 symmetric right between the left and the and the sketch look at the basin
75:12 range in sub surface, it doesn't like it at all. It looks
75:15 like something that is sketched here. maybe here and the subsurface, you
75:19 see a structure like that and the or the next reach towards the left
75:26 may have the same. So you this false stone that goes in the
75:31 very asymmetric. It's called low low angle normal fault. So it's
75:43 normal fault, just like we saw the Mackenzie stretching model. But it's
75:48 why one of those sequins. This one of the ones that could see
75:51 the entire cursed and a portion of little sphere and it looks more like
75:57 here. It will be. So other words, if you look at
76:02 rift basin, you would never come with this Mackenzie stretching model for it
76:07 it just doesn't look like it. , US scientists that work in this
76:15 of the us in the last 15 or, so they came up with
76:19 different model for continental rifts than Mackenzie the person who came up with that
76:26 ? His name is veronica. So the name of another scientist and he
76:32 came up with a veronica stretching Do you have a question,
76:37 Yeah. Yes, ma'am. On of your illustrations on the last
76:43 at the top right hand corner, you said, it would have looked
76:46 or it does look like um are the middle? There are those supposed
76:51 be your ridges or is it on edges of Yeah, that's a very
76:55 question. So, some of the are these foot blocks. It's a
77:01 that's a really good question. And but also this here, there
77:06 be four blocks here as well. The story is is that this is
77:15 you absolutely can't describe it by a that looks like this. Um It
77:21 the fault instead of being steep, are what we call shallow angle or
77:26 angle. And that just creates a different landscape. And instead of that
77:33 , you know, one rift like you see here, it creates
77:38 series of rift basins. So these you may see and they may pop
77:42 as riches, but also here maybe that pop up as riches. So
77:48 creates a whole different system, if know what I mean. But that's
77:52 just an excellent question. Yeah. you. Sure. So, you
77:58 see, he was a scientist in England and he looked at, you
78:06 , the european risk basis to not grabbing, for example, which are
78:12 and they look like this one here he developed his model. But in
78:16 Western U. S. There's other working. And this scientist, his
78:21 is veronica. He he works works works at caltech in California. So
78:28 to go to Bass and Bass in range in the western west. So
78:33 defends a different stretching model for sedimentary . And that model is much more
78:41 . And I'm gonna sketch it for and I'm gonna try to do a
78:45 job than I just did. Um will be the crest, it would
79:01 the mental legis fear Mental little sphere then he torched the rights you have
79:27 . And here's again Mental little And here on the meat, you
79:37 160 sphere now and then there are are these four blocks that I was
79:45 talking about um sometimes like this and between here you have settlements. So
80:10 the left here left of this you have crushed a mental little
80:16 That is not since between about here here you have a zone where the
80:35 since. But the mental little sphere not since see that. And then
80:54 here in clear you have an area the crust is not since, but
81:16 mental little sphere since. And then the right here you have a song
81:30 the christian mental it's fair about things or not. Um I guess I
81:49 it, I can see the Yeah. So when we started today
81:56 talked about um places where if you in the crisp with multi mental
82:04 what's going to happen in your colony if he's in the mental atmosphere,
82:08 not a crisp what's gonna happen with column. So that applies to this
82:13 here. He sent the crist, a mental little sphere. What was
82:19 happen source of science? I was if you sentimental little sphere, but
82:36 gonna happen? Right? So basically range is an area where you have
82:48 . In some places you have right? Because she was sent to
82:54 but not a mental little sphere. also other places where you have
82:59 You created some uplifts because she's sentimental but not the first. And so
83:05 that if you look at the basin range in the last week as
83:09 look at the topographic methods from point time. You don't see that one
83:14 , You see an area higher. . Higher, lower, higher and
83:19 this here would be the normal What do you want to call
83:28 A low angle, see it's it's different in character. You see that
83:46 the one that we just saw So I don't know what if you
83:49 to jump in here. But you imagine if you describe rifts on this
83:56 , your petrol model would look very , right? It's probably more
84:01 at least for some rich spaces. , but you can imagine that
84:06 this looks very different. So look , this here, it's the base
84:14 religious fear and it was what? many degrees 1300 something like that.
84:33 if you look at the basement where would be most heat um where
84:44 ? A therm is the highest. . So maybe maybe here right
84:52 So you think that um the highest may be flowing into an area that
84:57 not even the center of your basin about this. No, ma'am.
85:10 then I'm gonna turn it around so gonna ask you both of you um
85:18 whoever starts is fine. Give me me some differences between the model for
85:26 rifts in the basin range and Mackenzie for narrow riffs. What could you
85:33 up with? Um The first thing that the first thing that comes to
85:40 for me is that with the Mackenzie , it's gonna develop something that's
85:45 Um Whereas with this model it's not . Right? So the asymmetry,
85:52 it's striking, right? Yeah. you think of other differences um that
86:01 probably comes into play to where the at? So it's clear that this
86:08 a much more complex story than the McKenzie story that is in So keep
86:17 in mind. They all mentioned it weekend. Right? We asked about
86:22 . Um the story is more So be aware of that if you
86:29 a model like this layer on in life, be aware that these restaurants
86:34 more complex than the simple mechanics. models. Okay, I guess I
86:40 a question. Not sure. I like it relates to this, but
86:44 Petra mod one dimensional models that we're um and we're inputting our own heat
86:51 in there that are constant. Um guess uh you can get bottom hole
87:00 from the well data, right? would help you indicate what those heat
87:04 are. Um Yeah, okay. based on where you're at and like
87:10 know, say this scenario um that change. Um I don't know wherever
87:18 well is at laterally on this you know, you're gonna have a
87:22 bottom hole temperature. Zeki So maybe well as here, right? Maybe
87:29 is the location of your well here atmosphere hasn't come up much.
87:36 That this first thing for boundary hasn't up much. So that may be
87:42 different stories and then your well would here. Exactly. So it's much
87:48 complex. Right? And that simple that we put in last week.
87:54 when you have, you know, the well was richly drilled and you
87:59 a great bottom, you know, hole temperature. How can that,
88:09 can that measurement? The temperature help today when you put your pattern work
88:14 together with the temperature of the bottom , you know, if the system
88:21 reached the temperature which is suitable for hydrocarbons to be found. Right?
88:28 , but that tells you something about present day, Right? How you
88:32 use it in um she could You know, now that will make
88:40 a petrol model, even one It gives you a temperature depth
88:45 Right? So it gives you a . So you could plot your your
88:52 depth profile, whatever it looks like see if that predicted bottom hole
88:59 If it corresponds to the temperature that patron model predicts. I've seen in
89:05 we've done this for, you real data and real sedimentary basis.
89:09 example, Anadarko basin. We usually amazing good fit between the petrol model
89:18 the bottom hole temperature. So it usually works really well. But
89:25 , these bottom hole temperatures, you use them right? You can use
89:28 to help you constrain the present day . Yeah. Okay. And that's
89:33 something that we weren't provided in the exercise. Great. But you could
89:39 that if you would have that information , you can use that.
89:47 And the heat flow is something that always having to figure out in a
89:51 basin model. It's not something that's . Yeah, same two D and
89:56 D basin models. Right? The flow is something you don't have.
89:59 let's talk about that for a little . Now we're in the topic.
90:03 this heat is so important and the flow. So what are some constraints
90:11 have? We maybe we have a for temperature That's that is today,
90:24 or temperature 50 years ago when the was drilled. But it's still
90:29 But we also have paid your Remember one of them with veteran nights
90:38 its um he talks about the hydrogen and we talked about transformation Rachel.
91:06 right. What does veteran it reflect to tell you and how can this
91:11 you constrain the temperature in your Okay. Mhm. Tonight reflections indicates
91:23 maturity, correct? The temperature should high in order to get mature.
91:32 . So says something about journey. maybe your company gives you some for
91:40 reflections data points and you can use to constrain the temperature in your
91:45 Right? Because petrol petrol models predict your your feet tonight reflections would look
91:52 . Um if your model was So you can compare your model predicted
91:57 related sectors to the data points that may have and see if they match
92:03 they don't match what's going on with model. Either too hot or not
92:11 enough. Excellent. Yeah. So know them that you need to treat
92:17 temperature right? Right. Let's talk hydrogen index. What does that tell
92:25 ? It's related to the transformation Um It's I guess you know if
92:36 related to your transformation ratio then it's to your oil and gas window.
92:44 I guess I don't really have a feel for what that you know how
92:49 relationship works. Yeah. So it in a different course, right?
92:53 of the course that meghan already So it's a different course in this
92:58 . But in general it works as . So within your sediments there's organic
93:05 and that organic material becomes Karajan when sediments are buried deeper and as Karajan
93:14 mature to oil for gas the temperature higher and it's very steeper now at
93:26 moment that this carriage in starts to the hydrogen, it's called hydrogen
93:32 But hydrogen contents of your carriage in start to change because these molecules break
93:38 the new molecules that form they take . So the hydrogen, the hydrogen
93:45 of your carriage in will go down soon as maturation starts. So hydrogen
93:53 nexus, horizontal axis, vertical access steps. So when you're when you're
94:01 walk reaches that that first window the window carriages starts to mature and when
94:08 matures it takes up the oil and molecules that form they take up
94:14 So the hydrogen index changes, it goes down. So as soon as
94:20 hydrogen values start to go down, know what Karajan is maturing. So
94:27 hydrogen index. There was another number we gave you right that is usually
94:32 when petroleum companies take a sample of source work, they go to a
94:38 and they measure the hydrogen index. we have a curve on I'm
94:47 did we have a curve on Petro showed um showed something like that.
94:55 . No but what it does show the transformation ratio which is related to
95:00 . So transformation ratio tells you something you know the percentage of the character
95:08 has transformed a mature into oil or . So this transformation ratio if you
95:14 time in your horizontal axis and transformation on your vertical axis over time in
95:21 source work it goes from zero to value. Right? It goes
95:26 We saw that this time time So at this point in time tells
95:33 that correction starts to mature. So corresponds to this point. You see
95:40 when your hydrogen mx growth and this something that petra not predicts. Um
95:50 if your company has you know, index data or um paralysis was another
96:03 to get the transformation Rachel. If it has something for you, you
96:09 use it. So the transformation ratio , if you occur of transformation racial
96:16 versus time. Right? Maybe today know that your source rock is Um
96:24 right in the oil window. So transformation ratio would be 0.5 and you
96:32 you could compare that value to your predicted transformation racial. So there's several
96:38 if you would have all the time the world, there will be several
96:41 that you could see if you could constrain your model. Now why is
96:48 important? Mostly importance because you want know that at the time of
96:55 your whole petroleum system was in you need to not only have this
96:59 of maturity between you need a cap , you need to travel. So
97:05 need to know your modeling can tell this right? You need to know
97:09 he has all those components in Yes, ma'am. Makes sense.
97:24 , let's see. Um let me on. So I'm gonna come back
97:33 what I wanted to talk about next heat in basins. And so maybe
97:41 will do that first and then I'll back to a different topic.
97:46 what I'm gonna talk about in the hour or so, we're gonna have
97:49 break first is heat flow in basis heat in the basis because it's such
97:54 important topic. Each floor in So, when I'm sketching here is
98:09 surface of the earth, Maybe this the surface of a sentimentally basin.
98:15 I'm also going to sketch the base the sedimentary basin. Maybe it looks
98:19 like this. Who knows? So is the basement on the need to
98:26 basin and the sediment layers are here this segment based. So there's heat
98:40 from the deeper earth and this heat into the base and we call this
98:46 flow and that heat is coming from depths inside the earth. Do you
98:56 why? What produces that heat? do we have heat flow at all
99:01 from deeper inside the earth towards the . Any idea just this slightly molten
99:09 is um transferring through the atmosphere and crust. Sometimes that happens and we
99:22 that then maybe a magmatic intrusion. that word ring a bell?
99:31 So maybe there's more to work And that material finds its way up
99:37 into a volcano or not. But intrudes hot material in the basin.
99:42 that material here's a dyke and here's seal with magnetic material in a
99:49 Yeah, absolutely. And that would heat. Right? So that would
99:53 up the base with the basin. of that magmatic material may also be
99:59 larger debts. Maybe there's a large here and some diets here and so
100:05 he could also come from the So that's correct. That's one component
100:10 can think of another one. Tectonic also gives some heat. So this
100:20 activity may send the little sphere right a rift zone. For example,
100:26 bring the little sphere. Nastiness, boundary up to shadow, death goes
100:31 . She bring the whole material closer the surface explosion. What else?
100:45 , I will tell you, it's off the earth. So when the
100:50 was formed 4.5 billion years ago, um it was at first what we
100:58 magma ocean just completely molten and in course of its history it started to
101:04 down. It started from a crust little sphere etcetera. So that cooling
101:09 is still going on and that cooling the earth is an important component of
101:14 heat that comes out of the So sometimes this is court primordial
101:26 it's a term that you may come . Yeah. And there's one more
101:33 . And I'm sure you've heard of . Maybe you don't remember it
101:40 It's what we call radio genic And that is produced by heat producing
101:50 elements. So this is um important example, um you know, this
102:09 , maybe the basement consists of a night granite rocks. They consist of
102:18 that have some of these heat producing in them. And as you
102:24 the granite, is there the heat elements? They produce heat. And
102:30 that heat we call it radio genic is produced in the earth's crust.
102:36 that is some of the heat that into the sedimentary basin. Right?
102:46 in other words, they're still flowing the sedimentary basin. Sometimes we call
102:53 base or heat flow facial picture. talk about units. What are we
103:07 about here? So here's the top her sedimentary basin. Give us the
103:10 of a sedimentary basin and we saw heat was flowing into the base and
103:19 floor in earth sciences is often indicated Q. A. Smoke you.
103:26 that's heat flow and it is a , say 50 miller walls per square
103:35 . Writers again, minute, what's square meter, That's the minimums per
103:45 . So this is not a large . I think he needs like a
103:50 of soccer fields you know, to along light bulb. So it's not
103:55 huge amount. Right? You don't it when you touch the earth.
103:59 it's this heat that is flowing into elementary basis and also out of them
104:05 the surface of the earth. So if you deposit a sediments in
104:11 sedimentary basin that sediments when it becomes rock over time it will slowly start
104:18 heat up and it's being heated up this heat flow that flows into the
104:24 . Does that make sense? Um So we're gonna do something
104:38 I'm gonna pick a place in the basin made of this location here.
104:44 I'm gonna sketch what the temperature depth looks like, vertical axis is
104:55 horizontal axis is temperature. Yeah. what we saw last week is in
105:06 temperature increases with depth. So here are. Both the service of the
105:11 . So I'm gonna sketch it like . And um here we are at
105:16 source of the Earth. I don't what the temperature is. May be
105:21 and then inside the earth temperature And here we are. It's a
105:34 . Yeah. So this would be a g user. Now, mostly
105:43 you're in a sedimentary basin, the depths curve is like a line like
105:48 . Maybe it's curved a little bit completely raw straight line. But you
105:52 the picture right, temperature increases with in some places, temperature increases with
105:59 more rapidly than in all places. in some places um temperature depth profiles
106:07 little bit more complex. So you imagine that if you have a place
106:13 your sedimentary basin where you just you know, maybe 100 years ago
106:19 had an intrusion magnetic material may be sale here with hot hoops. So
106:28 that. Put something on my school with magmatic material. You can imagine
106:39 that locally can increase the heat. the seal may heat up the rocks
106:45 next to it. So if in location you would sketch a temperature depth
106:53 , it may look different. It look something like this, an increase
106:57 that. Then you get close to seal, temperatures increase sharply, then
107:01 goes down again and it increases like incidents. So in general, this
107:08 what it looks like. But locally some places it may have looked differently
107:14 time. Now, imagine that your work is right here at these
107:25 You can imagine that that source may been heated up by the seal at
107:31 point in time. So locally your may be behind it. Another reason
107:37 your temperature in your sedimentary basin may different from this cause is by groundwater
107:51 . So in the sedimentary rocks and basins, we have groundwater flowing inside
107:58 pores of these sedimentary rocks. When grandfather comes from large depths where it
108:06 have been heated up, it may higher temperature. So in other
108:16 your groundwater maybe going down and it colder temperatures down. So you can
108:24 that that locally affects temperature. Does make sense? So here in Petra
108:33 have a simple relationship between temperature and , but in real life this may
108:38 been different in a geologic past or may be different today. So be
108:44 of things like sales and dykes. basically magnetism that may have occurred or
108:55 something like this, questions about Um so in that scenario, you
109:09 to go outside of your, you , like a data set that we
109:13 given. You need to look at a, I don't know what a
109:17 sample be helpful. That could be . Also, what comes into play
109:24 issue a general much about the sedimentary . So you want to make sure
109:29 you, you know, maybe you've reading a little bit about this one
109:34 and then you recognize the geologists have folk um, is um Somewhere and
109:41 may want to look into the age the Volcanism. For example, if
109:45 volcanism is 25 million years old and may want to think about if that
109:52 have affected maturation of your source So you, you get some of
109:58 information from the literature, you read other people have found or thought about
110:04 basin. Okay, so you would background reading basically. And you
110:11 if this, if this basin has lot of volcanic features, I would
110:17 read into that. How old are have they affected your, your source
110:22 rested for work, maybe they're much and didn't matter. Maybe there are
110:27 place in the base and didn't But I would, I would look
110:31 that so I would try to understand been going on in this basin.
110:36 , okay. No, Alright. have a little bit more time.
110:43 I'm going to talk about a little more. So we just talked about
110:47 heat flux And a normal value is like 50, many of us m2
110:57 maybe 16. No, be certain nowhere. Hi, It would be
111:08 like 80 for hire. Sorry. . Would be something like more than
111:21 than about per m2. Yes. give you a gives you a
111:27 This is the normal value. This low, that's high. So the
111:32 is most very large. Right? you know, we're talking about a
111:37 of cents of many about prescription used make the difference between low and
111:48 Now one more thing that I want talk to you about is um temperature
111:55 in, we're gonna talk about a basically. So I'm gonna sketch a
112:00 simple risk basin. It's filled in sediments here is the mojo, which
112:10 very weird, but it's since below birthdays. And then here we have
112:15 little spare steam sir boundary boundary. , This was 39°C. Any idea what
112:34 mojo temperature could be 700. something like that. We're gonna say
112:47 or so. It really depends on you are from. Place to
112:51 Now. In the course we had ritual upper part now dr lower
113:03 What temperature able to fit with that between brittle brittle faulting and upper course
113:08 ductile deformation and lower list. 3 - 400. Excellent. And
113:24 we have our sedimentary basin and within sedimentary basin, maybe we have an
113:30 window. Any idea what temperatures we talking about here, 80° or
113:41 Do you agree? So that is here. Right. And I guess
113:54 there was always higher temperatures to be larger. Dept. Yeah. So
114:01 gives you an idea what you're looking . Let's talk about depths against
114:08 Typical sedimentary basin, what 4-8 km sediments or so, Can be 10
114:16 in a very deep basin. Can two km. But just gives you
114:20 idea, brittle ductile transition. Not typical depths of a breed of doctor
114:37 . Something like 15 km, maybe km, depends on where you were
114:45 depths Typically 35 km or so, 40. Yeah. Little sphere estimates
114:55 boundary is typically at the depth of like 125 km. Questions about
115:08 So this is where we are, not even sketched to scale,
115:13 If you you can see that But this is so this is where
115:16 are, really the upper part of first. No. Okay, so
115:27 I would like to suggest is that take a little bit of a break
115:32 then I'm going to talk about rift margins. Sounds good. Alright,
115:44 you in a few minutes. So what is really important for understanding
116:46 continents break up is magnetism before we there? Gonna explain to you one
116:55 thing. So we have here temperature dex now temperature depth relation is called
117:12 geothermal. Right? So this is base of the little sphere and
117:26 Here we find the esteem sphere And is say three general degree C.
117:39 Nigerian author may look something like this sense. Right? 39°C at the
117:50 of the little sphere. Now, do we have often broken is um
117:55 if so, why do we have ? It's because of the following.
118:00 this is the genus ERM there's another depth relationship in the earth which is
118:08 the sodas and the solid. This that temperature that a specific broadcast at
118:17 specific depth at the point it starts and solid is I'm gonna try to
118:24 here and it does something like So this year will be the
118:40 So in other words, the little , some producing religious fear normally are
118:49 than the solid. It's And temperatures the austere atmosphere are higher than the
118:56 . When you have temperatures that are in the solid, this you have
119:01 melting and when you have temperatures that hired and so did this, your
119:10 will start to amount. Then rocks to melt most all the minerals in
119:23 rocks melt at the same time. some minerals they start to work and
119:28 melt immediately all the minerals they melt . So only part of the rock
119:36 . So we call this partial So the estimates feel of the
119:48 It's a solid work, but it parts amounts in it And a partridge
119:54 is something like maybe up to 3% so. So any questions about the
120:04 between the geothermal and the Saudis. you get melting in your temperature is
120:13 than the Soviets. Right? So the geothermal crosses this ordinance is higher
120:17 the Soviets. Right now, let's a look at a continental rift zone
120:24 a continental rift zone we saw earlier the little sphere is thinner. So
120:29 other words, this 1300° temperature is be reached shallower depths maybe somewhere
120:39 maybe the little sphere has been since March in a rift zone. So
120:45 I'm gonna sketch this geothermal again here is the mute user, what do
120:59 see starting at these steps? The are actually higher than the solar this
121:08 receded. So now these works and below it will start to melt.
121:21 there's virtual melting as first. So does molten rock want to do molten
121:27 wants to go towards the surface? it may go towards the basis the
121:32 , maybe it points there, maybe goes into the crust, maybe it
121:37 a magma chamber in the crust and it may come to the surface and
121:42 may have a volcanic eruption. So is the reason why we have so
121:47 focus is um and rift zones, because the little sphere is since and
121:53 we cross the temperatures are so high are starting to cross the solid as
121:59 shallower depths. Makes sense. Right. Questions about this.
122:11 ma'am. Alright then, I'm gonna to classify out the geothermal is in
122:20 the higher temperature and the lower Right? It is when the transition
122:25 for the rocks. No, the leaders, you need know the Geo
122:31 , that's just the name of the dips curve. So this curse is
122:38 geothermal. Okay, we have another it's called and that solely does tells
122:49 the temperature and what Pepsi work starts mount and that solely does may look
122:54 like this. So is higher. temperatures are higher than the saltiness you
123:07 have melting if your temperatures are lower so you don't have melting. Does
123:14 make sense? And the solo this that changes depending on where you're
123:20 Yeah, it depends on the rock . So, you know, a
123:28 night will melt at a different temperature the sandstone. It depends on,
123:37 know, other compositions to rocks or rock types. They have fluids such
123:43 water built in, you know, minerals and when fruits such as water
123:51 part of your rock type, it much more easily and much shallower
123:56 So it depends on a lot of . So that's why I'm just sketching
123:59 as a simple curve basically. All . What I'm gonna do next is
124:09 through the next four points and this you have and it's called drifted margins
124:18 then we try to find it, share my screen eating. There we
124:44 , rich. So, I'm going talk now about rift of March.
124:49 again, um, you riffed the fear because you start to stretch it
124:56 . And at one point in this may result in constant to break
125:00 . Now, what we have seen first weekend is why these continental plates
125:05 under under extension. I'm not going go over that again. I'm just
125:10 move on. So where does rifting , rifts forum? They want to
125:16 there where the little sphere is where the little stray plates are
125:20 you can rift first there where everything weakest. So where is that?
125:25 the north? If you take a at this, um take a look
125:30 this list origin. It belts, zones, those are mountain ranges and
125:39 mountain ranges. So old mountain they are the weak points in the
125:47 plates. So if you have a plate and you start to stretch
125:52 it's gonna form these rifts bases It finds the weakest points so that
125:57 that's important, right? You're not break something up that is strong.
126:02 you need a weakness. So we them in old mountain ranges but also
126:09 to the atomic regions above mantle So when a mantle plume comes up
126:17 in the mental and it reaches the of the little sphere. Maybe this
126:21 the little sphere here it comes up then it flows into the little
126:27 It's gonna heat up this little sphere therefore make it weaker. And that's
126:33 this is a good place to form rift. So, it's gonna go
126:37 where you have a ridiculous any questions that makes sense. Right, just
126:47 now, what does the industry It makes faults in the brutal upper
126:53 . So this will be in a upper crust. It extends by
127:04 Doctor flow in the lower cursed. what we call fiscus deformation in the
127:15 little sphere. And then many places you have, you know, morton
127:23 available, you will see that some the stretching and feeling that space that
127:30 creates, it's filled up with magnetic , sort of a dyke intrusion for
127:36 . So we have faulting dr flow we can have magnetism. So dike
127:44 and the the continental rift zone is gonna go with whatever is easiest.
127:50 it's easiest to form a fault, will form a fault. If it's
127:54 to have some doctors stretching, it do that if it's easiest when we
127:59 it and create some space to fill that space with magnetic dykes will do
128:05 . This is what happens a lot the east african rift zone. So
128:09 we have a lot of my contributions the real world drift. For
128:12 we have a lot of faulting, it just depends on, you
128:16 whatever can accommodate that stretching. Right about this right now say we stretch
128:26 stretch and stretch and we come to point where the continent starts to
128:31 So now we have continental breakup after breakup. You form these rift
128:37 Right? These marches that we talked earlier today, know several things may
128:44 at that point in time when there a continental breakup. This continental breakup
128:51 be accompanied by large volumes of melt party animals, so we call it
128:58 stuff. And if you break up continent and as a result of
129:03 a lot of magnetism occurs? A of volcanism occurs. The margins of
129:10 continents that are formed them are called dominated margins for volcanic margins. If
129:16 continental breakup occurs and there's not much is a more magnetism going on.
129:21 call these merchants magma poor or non Marchionne's. Yes, after continent
129:29 one of two margins forms either a of vocalism associated with breakups and reform
129:36 dominated margins or you break up a and there isn't much vocalism for magnetism
129:42 on. And then you just have margin without, you know, volcanic
129:47 on it. We call that magma margins makes sense. Can I make
129:54 comment? I know that these terms margin of volcanic margins are very common
130:02 literature, but I think they're a bit of a misnomer because volcanic volcanism
130:09 an external extrusion process. And you , these Yeah. You know that
130:15 margins can actually, you know, can be a lot of whatever uh
130:22 magma like under planning and things like . So, I typically I'd like
130:27 say that I acknowledge that these terms the literature because you can't avoid
130:32 but really magmatic and a magmatic are think more descriptive because they're they're not
130:40 restricted to exclusive processes anyway, that's . Well, yeah, that's
130:46 Um so you can think about, would you see a lot of volcanic
130:54 magmatic activity on one place, but in another place? Right. Maybe
130:59 has only to do with what we the magma plumbing system. If you
131:03 melting deeper inside the earth and the is morton works find their way towards
131:08 surface. In some places, they their way towards the surface much more
131:13 than in other places. And so can imagine that when you form a
131:19 margin and you don't see any volcanism evidence of magnetic activity, maybe it
131:25 didn't come close enough to the surface us to observe. So, there's
131:30 an observational part to it is what see, right? We see some
131:36 have a lot of volcanism and we other margins don't, but that doesn't
131:41 mean that the market that don't see is um don't have like a lot
131:47 intrusions. For example, in the , we might just not be able
131:50 see it. But I'll show you a few minutes the map of the
131:56 , it shows where people see a of folks in Ism on margins and
132:01 people don't see it at all. what is remarkable is the cut
132:07 So, you see some continent Marches is um africa and others, there's
132:14 . And so you can wonder why is the case. Is that the
132:18 because the modern rocks just never came enough to the surface and you just
132:23 see it? Or is there something going on? So this is a
132:28 that is still going on. But may be wondering why would I
132:33 So what you care is because everything um versus non volcanic tells you something
132:42 the heat input into the sedimentary Right? If you're looking at a
132:46 with a lot of mechanics, maybe just heated up the source rock enough
132:52 maybe it's over here to source So if you are a petroleum geologist
132:57 on petroleum system, you may want keep in mind whether there has been
133:03 lot of volcanism or magnetism at your , it's gonna be very important for
133:10 , for the maturation history as you imagine. Now there's a third type
133:15 marching and that merchant, I'm gonna it here transform merchant and I'm gonna
133:22 to you in a little bit more this. So the first one magmatic
133:29 margins. And this is a term that um, I don't really like
133:35 audio doesn't really like that. People it a lot. So we're just
133:38 here. These margins are formed by and thinning of the crust. So
133:44 the roof spaces that we've been talking so far the same for the magma
133:48 margins, There was extension stretching, of the crust. This transfer
133:54 they're different. So they form because have, you know, two tectonic
133:59 that are moving more or less parallel one another, which we have and
134:03 have a transform fault. Right? then they broke up. So come
134:09 to that in a few minutes. let's take a look at this map
134:16 . So all the coastlines here that a color by the X. Blue
134:21 red or orange are what we call at margins. So those margins formed
134:28 extension and singing the little sphere, form a continental rift base and stretch
134:33 further and at one point in time constant over break up. That's all
134:38 you see in orange, red and . Some of these merchants you can
134:42 they have a very thick black Those margins are what we call transfer
134:50 . So they didn't really informed by , they formed more like by hearing
134:55 was a large shear components when those broke up. Now the ones that
135:02 indicated to blue colors that color those margins, when people look at
135:08 today, they don't see evidence of is um where of a lot of
135:13 is um These margins look like sometimes no foe can IQ or magmatic activity
135:17 all. And that's what we call magma. For the ones in
135:25 If you look at those margins, see a lot of evidence of broken
135:28 um not so much today, but the time when the continent broke
135:34 So for example, in the north , when you look at those margins
135:39 are called red here, the magma merchants, you would see and can
135:44 that later evidence of volcanism, you see buried volcanoes in sedimentary layers or
135:50 may see a lot of sales and where you may see lava flows that
135:54 floats out over the surface on those when there was continental breakup. And
136:01 there are margins that are colored orange they call it orange because it is
136:06 really certain whether they should be in magma poor or the magma dominated.
136:11 the volcanic poor, non volcanic volcanic category, it can be because we
136:17 have enough data or maybe the data are not, you know, they're
136:23 each other. So there's still a of uncertainty questions about this matter.
136:34 then let me move from. So gonna look at soon. Very ideal
136:40 vertical cross sections along March. So looked at well earlier today and last
136:47 , but I'm gonna, we're gonna at it again. So what you
136:50 here towards the rights, the ocean and what's the left is the
136:59 Somewhere here would be the cost vertical axis. Here's depths. This
137:11 something like maybe 40 km gives you idea of the skill, personal skill
137:19 indicated here. Now if you look these magma poor margins and some of
137:26 you see for example here in Liberia europe or here the Canadian margin.
137:36 is what I can check at the site. You see, oh you
137:41 what the coastline is? Probably more . Let me put the coastline like
137:46 , coastline and adam corner called this continent ocean boundary. So the boundary
137:54 the ocean and the content and coastline here. Sorry about that. So
137:59 you look at these merchants adepts, see a lot of faulting and much
138:04 that is low angle normal faulting. you see these basins filled up with
138:20 . And this is the region that faulted and stretched as you can see
138:25 the scale. This is hundreds of , hundreds of kilometers wide region stretching
138:34 extension and sedimentary basis. Furthermore, you see is that the cursed which
138:42 shown here in the light yellow, becomes sinner and sinner towards the
138:48 And then here you are at a in time where you maybe have a
138:53 crystal walk left, but there's probably mental little sphere anymore. Continental mental
139:01 here would be continental. Mental little and that's almost completely gone.
139:12 when you're there. Now then let's a look at the ocean part of
139:18 um of the march. In so the ocean part we see a thin
139:26 of crust. Let me see where can see it here towards the rights
139:33 the bluish color is the new ocean . And then here in this darker
139:41 , you can see a layer of now then there is this large area
139:49 in this region here. We don't have continental crust left. We don't
139:55 oceanic crust. So there's a large here that there is no continent,
140:01 across an ocean across no crust at actually. So that's really weird.
140:06 we have an area here where you these settlements on top of the Mental
140:11 no crystal layer which is completely And so again, it's under laying
140:18 mental many scientists think that at least of this Mental may come from the
140:26 so that its continental mental atmosphere and oceanic, but there's a lot unknown
140:31 it, we actually don't really Yeah. So to summarize towards the
140:37 is the continent towards the right is ocean basin. The continent seems the
140:42 of course seem to think regularly towards ocean basin. At one point in
140:46 , you may see a crystal block , but that's it. Then there's
140:50 whole zone where there's no chris present all. And then in the ocean
140:55 we have the oceanic chris present. , if you look at this transacted
141:02 now completely messed up. Very sorry that. Um What you don't see
141:10 anything that looks like a volcano or magmatic intrusion or anything like that.
141:17 So it doesn't mean that you that can't find it here but it's not
141:22 in large amounts. So we see evidence of lava flows, no evidence
141:32 volcanoes? A lot of magnetic material makes it towards the surface. You
141:41 that right? When you see your , it made it towards the
141:44 but most of it stays on the , There's little or no evidence here
141:54 optical magnetic intrusions. So magnetic material just didn't make it towards the
142:00 it may be there at large but we have no clue. We
142:04 look further. We can't look at depths that maybe these steps we can't
142:12 see. That's all I need is . Yeah. So, and we've
142:17 drilled a hole that was deeper than here. That would be the deepest
142:23 hole ever drilled on average margin. we don't really know what's going on
142:29 or here or here. How do explain the igneous crust this one,
142:38 . So this is new oceanic So that is that ocean crust is
142:44 at the mid ocean spreading rich. so the idea is that if you
142:52 you you know, you you stretch continents enough at one point in
142:57 you bring so many holes. Nastiness up to shadow that you start to
143:01 a lot of rocks. Those rocks rocks go towards the surface, they
143:06 and they form new ocean crust. new ocean crust is always magmatic
143:12 So it forms from cools down rocks mental death. This molten before that's
143:18 an excellent question. Okay. What is Okay, so beneath the yellow
143:26 rocks is continental atmosphere. And beneath new ocean crust is continent is oceanic
143:34 . What is the little sphere beneath region of hyper extended crust and all
143:39 other stuff? That continental atmosphere or ? Ah There are many people,
143:49 scientists think that this is continental, mental little sphere. You know,
143:56 may wonder what happens with the Mental ? Um I think most scientists believe
144:04 this is continental. Mental, Continental will be present here. Right.
144:08 it has to be doesn't mean it be you can't be producing oceanic litmus
144:13 beneath continental crust. Right. I it has to be continental, doesn't
144:28 ? So I haven't because oceanic mental which should be present here, that
144:37 the Mental that stays behind after you've out the molten rocks that form the
144:43 across. And so if you look that definition, this is oceanic and
144:49 needs to be continental. Does that sense? It's ocean, it's oceanic
144:56 beneath oceanic crust is new. It's . It's created at as the and
145:04 mean, you know, I got mean I'm sorry too. I hope
145:09 don't mind me speaking. I mean know you have a lot of
145:12 I'm sorry but I mean this I that this is a this is a
145:19 popular model these days. It has for the last 10 years or
145:23 And I mean everyone and their sister mapping, you know hyper extended continental
145:29 and hydrated upper mantle and you and now Sir privatization is a is
145:35 you know it's a poison racial indicator all this stuff. I mean it's
145:40 popular but I mean you know if look back at different super kind of
145:49 , you basically have continental with a and oceanic atmosphere and and anything that
146:00 subduction is going to get it created some kind of so anything that doesn't
146:05 duct is continental crust. I mean some time, but so the nature
146:14 the litmus fear to me is just modeling the oceanic continental. And um
146:22 this is not and if you have this has to be, it has
146:27 be continental crust. I mean they words like as you know, it
146:32 continental affinities is a phrase that's that's . Anyways, I'm just stop
146:38 I'm sorry to be honest, I , I have doubts about this model
146:46 that's what you're talking about. So because um you know there used to
146:56 , we just mentioned it right, magma ocean when the earth was being
147:00 first magma ocean, that's how we out four billion years ago. And
147:09 happens is that the lighter materials in magma ocean, they found their way
147:16 the outsiders, I started to form crist Now if you take lighter minerals
147:23 of a pool of magma, the that leaves is left behind has a
147:29 different composition than when you first started right. It takes some stuff
147:34 preferably some minerals and of others. now this changes in composition and that
147:40 on and on. You know it arc regions, continental rift zones where
147:46 take magma out of your justino Today we changed the composition of that
147:54 here so it's no longer primordial originally but it's changed and that is of
148:00 also the case here in this particular we have continental crust above Mental and
148:09 continental crust formed once from the minerals were extracted from the Athena sphere or
148:16 Mental at that point in time they like they found their way upwards,
148:19 formed the earth's crust. So this here, it's also not original
148:27 we call it now continental because it's the continents. Now the same as
148:33 . So you start out with oceanic mus figure it's melting some minerals are
148:38 out, they become ocean first and what's left behind is now a different
148:44 because it's below the ocean basins we it oceanic mental atmosphere. So what
148:50 can think about is are the minerals have been taken out here by the
148:54 . Different from the minerals that have taken out here. And if so
149:00 mental little sphere, that little sphere stays behind here and here will have
149:04 slightly different composition? So I guess is one way you could define
149:12 mental atmosphere, ocean biosphere versus continental sphere. I don't know. I
149:20 your point that there are non cyclical in the earth over time. I
149:27 certainly, you know, the amount radio genic radioactive elements is finite and
149:33 those decay then that's just a one or one way. But um plate
149:39 started 3.2 billion years ago. And been a lot of, you
149:45 there's been a lot of recycling of throughout all that time throughout many supercontinent
149:52 . So and we have bits of archy and with atmosphere across and let
149:58 fear protozoa, you know across the this fear and and of course we
150:05 younger fans. So it's tough. the you know, the trying to
150:12 I think, you know, mental , this fear differences between our Kian
150:19 protozoa and fan. And I think a pretty big challenge. But that's
150:23 you're saying here, there's you're saying are different. But I don't know
150:27 I if I if I could even mean how how do people how do
150:31 know, other than looking at, guess volcanic says that you know,
150:37 through those, through those bits of age crust. And I you
150:42 I wonder if you have someone done . I mean have we just decided
150:48 the the atmosphere beneath, you the different eons of continental of continental
150:57 sphere are are different compositionally. I know. I think so. Um
151:03 think so. But you're right. this mental here has confected,
151:08 Just like this mental here like this here. So there is a,
151:13 know, this is not primordial, is not primordial, this is not
151:19 , it has all been changed in course of these billions of years and
151:23 been right, there have been many episodes and yeah, so I I
151:34 I I don't know, I don't am not a big fan of this
151:38 simple model. Um I'm not a of it explains anything right? It
151:45 explain. So hating you. really good question. Why?
151:50 Why is that blue cluster? So came up with a made up answer
151:54 you'll find in literature. But the is, nobody knows, you
151:58 why is the first here and not ? I don't know, Maybe it
152:03 and maybe data have been interpreted incorrectly whatever. It has certainly never been
152:09 . This has not been drilled outside a non magmatic margin. And this
152:15 this this depth, right, just there. Um So I don't
152:23 I'm gonna say, I don't And this this sketch. I I
152:30 know either. I mean, I I agree with you. I don't
152:33 don't I'm not crazy about this, there's only one margin where this this
152:39 these processes, these processes that are are thought to underpin this this
152:45 There's only one margin on the planet this is actually and of course,
152:50 know, it's an offshore Iberia offshore and Portugal. And and but there
152:58 people that that love this model and and they shoehorn this thing into every
153:06 on the planet. You know, mean, it's just it's amazing.
153:10 , I'll stop complaining anyway, I'll interrupting my bad. So what I
153:15 I think is really good that you're up is um how much there's unknown
153:22 . So you can later in your work as an oil company that is
153:26 fan of this model or you cannot bread. Well, that is not
153:29 fan of this model. And this this is all we have. I
153:34 the truth is we really do not . And um yeah, maybe that's
153:39 margin on Earth. So this is actually in europe, maybe that one
153:44 earth looks like this, but it explain anything right. It doesn't mean
153:51 in that sense. Um maybe we talk more about this at a separate
153:59 deal. So I have friends in petroleum industry that absolutely hate this model
154:05 they say they would interpret the same very differently. And they have.
154:09 there's also discussion there about how to the data sets. And I can
154:18 you one example where there's um where you no disagreement about. So you
154:26 these tiny fault blocks here. That is sketched earlier. So way
154:30 way it's sketched here, it looks these are the faults. This is
154:38 fault, this is a fault and is a fault. But then many
154:44 in the Petroleum Ministry have told me it's not correct. But these are
154:49 faults. And then you can say well why would that matter? It
154:57 matter a lot. It tells you the marching developed very differently and it
155:02 give a very different meaning to what's here. So there's a lot of
155:07 about these topics. And I think end point is at the moment we
155:12 not know it needs a new generation you hate and to start thinking about
155:18 and see what you think um there I come from a phase where um
155:25 there hasn't been too much discussion about , but too much. There has
155:28 a lot of discussion, but maybe so much progress if you know what
155:32 mean. Um Anyways, what was going to say the following. So
155:39 these are, this is a merchant you're looking at, you you've got
155:44 from a basin on this March in um you know, your basin has
155:50 of patrol. So where is that ? The basin would be anywhere probably
155:56 here to hear. It would not here. So this here is thought
156:03 be a very thin layer of You know, it's not very deepen
156:08 enough. It would have not have . So you're looking at something that
156:14 in this region, so more on merchant side and not so much,
156:19 know, in this ocean basin Right, let's move on. Um
156:30 these are terms that you may see literature, this is considered extreme crystallizing
156:39 . Sometimes people call these hyper extended . Now I'm gonna ask deal deal
156:52 of that term. But for me that is called hyper I don't I
156:58 like that term. I would just people to say what's going on.
157:02 I would like people to say, we see some crystal blocks.
157:06 you know, but no crystal layer or no Doctor Crist anymore. But
157:11 term you will see a lot in literature called hyper extended margins.
157:16 that's a that's one of the favorite that they use for that.
157:21 and then, and then the unwrapped , you say exposed mantle. I
157:25 have a problem with that. But also used the term Exume mantle.
157:31 , and I think that's a little backwards because you don't, you don't
157:38 the grave from the, from the . Right. You exhumed the body
157:42 the grave. So what's what's exhumed actually the crust. I mean that's
157:48 semantics or whatever, that's just whatever is. But yeah, mantle
157:57 but it's actually cross the legs. I always say unreached mantle is the
158:03 is the term Burbage I use but I never say hyper extended, you
158:10 , we needed, I've never used word in my, I would
158:14 I wouldn't speak it out, but see it to be a word,
158:19 aware of these words exposed, sunroof hyperextended, that's what people are talking
158:26 . So this is what it looks . So you know, if somebody
158:30 up with that term for you, have an idea what people are talking
158:35 . This is what people are talking and they have, they talk about
158:38 necking zone. I mean these people really, they're really uh you
158:42 there's for the different bits along this , this wide rift, they have
158:49 lot of different terms that they use necking, like I say necking zone
158:54 I don't know what the other ones . But so I'm gonna I'm gonna
158:59 that long because this is a term you may see as well necking
159:04 you know what they call making when have here, the the crystals sitting
159:11 , right? You see it here here. So they call that
159:15 So the neck, this is how sketch a neck. Yeah,
159:24 She did. That's just how people it. It doesn't mean anything,
159:30 if you see the term necking they are talking about this, this
159:36 here where you have sinned crust. this entire area where you've sinned
159:40 people call that a necking song at Aggie. You there's a passive
159:47 at least one or two oral sessions then of course, one or two
159:51 sessions and they're just populated with these these models. And it's always the
159:59 guys presenting this stuff and when they the talks, they all sit together
160:05 ask each other questions. And it's , it's really bad. It
160:12 it's it's just a couple of groups the world who do all this and
160:20 Yeah. Anyways, so, you , some terminologies, there are other
160:25 that we need to think about, you may hurt. Um oh,
160:30 about this one deal a proximal and . So March in, have you
160:39 of those terms? Oh, absolutely, yeah, yeah, approximately
160:42 till there's there. They're part of part of the jargon. Yeah.
160:49 proximal is everything that's like here. , actually not proximal, I think
160:57 be everything here. And this thought be everything here. That's my
161:05 I think everything that's that's outboard is and everything that's sort of in
161:12 Proximal. I'm using more jargon inboard outboard, which just means Yeah.
161:21 a lot of terminology. Yeah. . So by the way, I
161:29 an american for this exam, I'm gonna ask you the terminology but I
161:36 it's good if you've seen it it rings about next time. May
161:40 a paper about the necking zone in distal margin. You know, it
161:45 something that has to do with right? And you may remember all
161:48 this, but there's just a lot , a lot of terminology associated with
161:52 drifted margins. So that's one reason we're talking about them. Let's talk
161:58 little bit more about this base. so maybe this year is the sediment
162:04 that you're studying with patrons. And let's talk about um the age of
162:11 basin. It's the age of the basin older or younger than the oldest
162:19 curse that you found there that has been formed all older. Yeah,
162:33 was going on first, right. had drifting from the drift zones later
162:38 was continental breakup and later you formed ocean across. So these basins,
162:44 can be fairly old. So the basins again, they have the same
162:50 as the rift basis. We talked earlier. There may be many next
162:54 each other. So often it's not , but that rift zone may just
162:58 continued to rift over the course of . Let's see what else. The
163:04 , you know, these sediment piles be kilometers, can be up to
163:09 km or eight km or so. where do these sediments come from that
163:14 see here? What's the source of settlements, continental crust or make me
163:23 or. Right. So there's components when they were on the part of
163:30 continent. Right. So what you flew for your eroded off the mountain
163:34 etcetera after the war area was emerged water. So maybe after continental
163:41 more sediments were being deposited. They still come from rivers etcetera. But
163:46 may also be marine sediments now and marine sediments, they are more organic
163:52 . So they form better source And around the time of breakup which
163:57 often see is like a marsh or environment and in such an environment you
164:06 a shallow layer of water, you a lot of vegetation. The vegetation
164:11 decompose, correct. It's preserved. you form rocks with high organic
164:19 So yeah. Um that's what's going there. Right. I have a
164:29 question. Yeah, go ahead. these these sediments are older in a
164:37 risk but some are co evil. some are even younger. Like these
164:42 out here in this ocean crusts. , those younger. So they
164:47 Yeah, exactly. This all the one from the continental rift phase.
164:53 is older than a time of continental . Then there was a time of
164:58 breakup and there was some sedimentation So these sediments may have the same
165:03 as the oldest sediments here. And after breakup we had new sediments being
165:10 , some may come from river So may be marine sediments from from
165:15 ocean basin. They will be at top here. And these all can
165:21 younger than continental breakup. So they they are even younger than the than
165:27 know that notion. Of course, they're deposited on top. Right.
165:31 the oldest sediments here, oldest these sedimentary basins, they're very old
165:37 going upwards, there's young and and we end up with sediments that were
165:42 after constant breakup. Does that make ? So these basins here, these
165:50 basins that rifting occurred before continental After continental breakup. These patients died
165:57 and they just cooled down but it mean that it was more sedimentation.
166:03 point. More questions about this. right. Um I'm gonna skip
166:18 I'm gonna show you an example of reel magmatic magmatic margin and what it
166:24 like. And our example is gonna from the new fountain area. So
166:30 new fountains which is a consequence of . If you break up the ocean
166:35 , they're in the stretch, they're look at what we call a seismic
166:41 line. And so, my first . So this word here is a
166:52 . Sorry, I can't really right very clearly seismic reflection line.
166:59 that's a geophysical data set. My question for both of you is do
167:04 know what a seismic reflection line Huh? Maybe you think maybe you
167:16 . It's like purple and like blue yellow and have like different amplitudes and
167:23 . Great. So it's like a , right? That shows the subsurface
167:28 section through the subsurface. And often see what we call reflectors. That
167:33 be what you say, blue or or black and white. And what
167:39 also see often if they're false, if there's false, you can see
167:43 offset in your reflectors. And how create such a seismic reflection line is
167:51 um sent a wave inside the earth that here's the wave, a wave
167:57 and it can be by an explosion by a, you know, fibrosis
168:03 equipment or something like that. He a seismic wave into the earth.
168:07 we basically we shake the earth and seismic wave that travels into the
168:14 It's going to be reflected off if have a different layer of rocks.
168:19 maybe here you have a sandstone and you have a basalt, it's gonna
168:27 off that interface and come back and you record it and you line it
168:31 up, you get what we call seismic reflection line. So it literally
168:35 you rare seismic waves reflected off you know, whatever is going on
168:41 the subsurface. So it gives you about layers in the subsurface. And
168:47 you think you can see things like really well on those seismic lines.
168:52 we often use that to get an of what is going on in the
168:59 . So what is often done in petroleum industry is that people try to
169:04 these seismic lines, the seismic reflection from a basin. Because that gives
169:10 a provisional vision and you get a to look into the subsurface. You
169:16 look underneath a sedimentary basin. So you can look at these different
169:21 sediment layers. For example, you figure out whether there's false trips,
169:26 where the bedrock is the basement how thick your sedimentary basins. So
169:32 often do that. Petroleum companies often that. When you see shown on
169:38 map here is a map here, can recognize new fountains and this here
169:44 the continental shelf. So that is shallow part of the ocean basin.
169:50 it's continental cursed with a thin layer , you know, ocean on top
169:55 it. And then here you have steep drop off into the deep
170:01 You see that it's a steep drop . Now. When we looked earlier
170:06 this, this this cartoon figure of set of a rift margin. We
170:12 at, where would you find the ? Where do you go looking for
170:16 ? We concluded this was on that area. So that's this area here
170:21 then just outside of of it so to the shelf, but in the
170:25 ocean basin. So that is the basically here. Now, what you
170:33 is that that is the place where are going going to try to collect
170:39 seismic reflection data sets these vertical lines you see here. The black ones
170:44 the red ones. Those are locations the map where people have these seismic
170:50 from. So, you know all them is a separate seismic line.
170:54 one is a seismic line. This on the seismic line all the red
170:58 . And if you combine that you have quite a lot of seismic
171:03 . And so it gives you a picture of what's going on in the
171:11 . So before we go into discuss It is 407. So let's take
171:18 um you know 5-10 minutes break or . Okay, Great. You're all
171:57 for another 45 minutes. Excellent. here you see an example of a
172:06 reflection line. Sometimes we call it seismic line. So what do these
172:19 look like the vertical access instead of being depth? It is time in
172:28 . And what you see here, is not time. It says
172:32 W. T. Time. That to do it. We time
172:43 So what is to wait time? remember here at the surface a seismic
172:50 was sent into the earth. It down until it matter reflected and it
172:56 off and traveled back. So it traveled twice down and up the
173:01 So that's why we call it to time makes sense. Right. So
173:06 could see, you could understand the access. It says it's time in
173:12 . But you could understand it as . You see that the longer the
173:18 turf old, the deeper that reflects us. Alright then let's take a
173:24 at the horizontal axis. So the axis is a distance annex a
173:35 To open. Such a distance on seismic reflection line is not given in
173:43 , what you would expect, but given in what we call short
173:47 So here was a location where a wave was put in the grounds.
173:54 was location where seismic wave number 601 put in the ground 1201, et
174:00 . So when people do get a reflection data, they do a seismic
174:05 experiments. And at many places they have like an explosion that sends size
174:11 to the grounds. And those locations those explosions, they are a certain
174:17 apart. Maybe every, I don't , um 100 m or something like
174:23 . So sometimes instead of saying, , this distance is 100 m,
174:29 put in what they call short points sense. Right? So short
174:34 you could read as horizontal distance and a time you can read as vertical
174:40 . So then if you look at seismic reflection line, which you see
174:45 , he basically said the subsurface Now let me explain this to
174:51 Hayden, go ahead. Yeah, was just wondering, did you say
174:55 was a standard like interval for the distance between shot points. It really
175:01 . It varies very greatly. So doesn't mean anything, You know,
175:06 know, it's not centimeters or it needs to be more than
175:10 But it really, some studies it's very different from other studies.
175:14 that's a really good question. But often when people show you a
175:20 like this, they will not tell what they think the depth is and
175:24 will not tell you what they think horizontal distances. So that would be
175:28 question. You know, if you're the audience, you would ask that
175:32 , basically think this stupid that people give an act and estimate, you
175:39 , because you don't know what you're at. So we're here. The
175:45 of this line is shown on this , It's like 41° North, 66°
175:53 . And I think when I look this, I think this is the
175:58 found land margin. So I think the same margin that we were just
176:02 at. And here's the seismic So here's the golden inside, here's
176:07 ocean side. And I think that is exactly at where you have that
176:13 drop off from the shelf to the ocean basin. That would be my
176:18 that we're looking at here. And what I think this line means this
176:23 here that this is the ocean bottom to the bottom of the ocean.
176:32 this is all ocean based and basically . So you're looking here or that
176:39 colors they are of the subsurface. I think you're looking at here are
176:45 layers. You see that this layering then you see it has a little
176:50 of a shape like this and then you have a layer that's ending abruptly
176:55 . This could have been moved down an under underwater landslide or so
177:02 You see maybe some faulting here. think these are you know gravitational false
177:10 than tectonic faults and in general you see the sediment layers dipping towards the
177:16 basin. Here's indicated something that is seaward different reflectors and the C.
177:25 different reflectors. You can see them . So here I can trace a
177:30 reflectors. I don't know if you see them and they dip towards the
177:35 . You see that they don't dip the continent. They dip towards the
177:38 . So people call them, see dipping reflectors and that is often appreciated
177:43 SDI or earth. So um these we're different reflectors. They have been
177:50 in some places so we know what are and what they're basically our our
177:56 flows inter bedded with layers of So because there are lava flows embedded
178:03 sediments they cause reflectors. And that why you see them so clearly.
178:08 at least you know the trains, can see them clearly see where different
178:13 . So when you have those, is always signature of that, there
178:17 have been at least some magnetism. ? Otherwise you don't form a lava
178:21 . So that is often an indication a margin with magnetism. Anyways,
178:29 is this is the example that I to show you. So it's such
178:34 reflection lines. That is how people the information of what a rift that
178:40 looks like beneath the surface. So just what I wanted to show
178:45 So, let's go back now to , this non magmatic rift of marching
178:52 the right. A little inside map you where the interpreted seismic reflection line
178:57 that we're looking at here. what we're looking at here is you
179:02 this often in the literature or in it is an interpretation of assessment reflection
179:08 . So the vertical access can still instead of death, can still be
179:14 to wait time. The horizontal access still be um short point distance or
179:21 like that. Whatever people come up . Now, this is an interpretation
179:27 a real seismic reflection line offshore new plants. So this is of a
179:33 magmatic margin. The continent is here the left, the ocean basin is
179:47 the right and the entire areas Now, immediately, when you look
179:53 this line, you see it looks more complex and quite different from what
179:59 cartoon sketch looks like right. So the left here, I can show
180:05 below the figure you can see the you know the legends of the colors
180:12 this here. That's all cursed material the left. So we call it
180:24 here towards the left would be continental since somewhere here is the continental ocean
180:34 and which the rights would be oceanic . And you can see when you
180:39 at this, it's very difficult to where your continental crust ends and where
180:44 oceanic crust starts. You see that isn't really different. But you see
180:50 the right side here, you see this crust has a lot of faults
180:57 it which is very typical for oceanic . So a lot of people would
181:03 that this is probably oceanic crust and this is continental crust. But you
181:09 it's not easy to say where you now. Then you see um all
181:17 layers here, the darker green. hope you can see that that will
181:20 an old sedimentary layer. You see here as well, younger sedimentary layers
181:26 top um there can be turbid ites deposits. You see that often on
181:33 routes that march in. But what don't really see is anything that looks
181:37 it is magmatic or volcanic. So is basically absent. You see it
181:42 some places, maybe two or but there's nothing large going on.
181:49 this is what looks like. And , the message is, it's really
181:54 and you can imagine by looking at like this, it may be very
181:57 to figure out which is what this modest continent, where is the
182:03 Um So people have a lot of with that. One other thing that
182:07 want to show you is the And there's two locations here that are
182:16 groups cite something. Sites 12 Sites 12 76. Those are places
182:24 people have drilled wells through the sediments there are everywhere in the ocean
182:31 hundreds of switch wells. And often data sets are public and you can
182:36 look at them what they look So those are two wells that have
182:39 drilled. This one works too When it was drilled, something went
182:47 with the drilling and it reached probably upper foot or so of that crystal
182:54 below. But we're not 100% short towards the left. Never reached the
183:02 , never reached the crest. It was drilling through sediments and at one
183:06 in time it actually drilled through a . So we know there's a little
183:11 of magnetic material then there and then came out again into sediments.
183:17 you know, you may wonder why people just drill holes everywhere,
183:21 And we will know what it Well, it is often not easy
183:24 drill such deep holes in through sedimentary or in the crew store in the
183:30 basins. So, the data is not as good as we would like
183:35 see. Just wanted to mention Any questions about this. All
183:43 Here's the, you know, a portion of a seismic line you see
183:48 a little bit. The reflectors, see that, but it gives you
183:51 idea of how difficult it is to at the seismic reflection lines. All
183:59 now, let's take a step back magma poor emergence. We have many
184:02 them on Earth, if that you saw. And there they are defined
184:08 a lack of significant magnetism. there may be something, there may
184:12 a silly or something like that, not a whole lot. So,
184:15 do they form? Well, when riff to stretch to coast we saw
184:20 today, you often have a lot volcanism, right? You have
184:24 you have volcanism and a real ground . We have volcanism in the East
184:28 rift zone that's normal for continental rift . So, people have been thinking
184:33 how can you break up a continent not produce a lot of magnetism and
184:40 don't really know why that is the . Maybe there's nothing special going
184:44 People have also come up with One explanation is maybe this rifting
184:51 but it occurred about mental that is colder than elsewhere. Maybe the mental
184:57 is only 1250° in some places and 1300°. You can imagine that when the
185:03 is colder, your chance of melting is much lower and if you're gonna
185:08 it, you're going to produce much melt. People have also talked about
185:13 and this is a term that you see a lot in the literature if
185:17 working on sedimentary basis, maybe the here is what we call partially depleted
185:25 , you know what that means? means that people think maybe the mental
185:30 has been melting before, it was before, so all the minerals that
185:36 easily have been removed from the So now if you tried to melt
185:40 , you're not going to be So that's what partially depleted mental means
185:45 we have melted before and all the molten minerals they have been removed,
185:52 then what's left over is not called easily. The last explanation is,
185:57 think maybe these magma for merchants, form of the very slow extension,
186:04 duration of rifting so long that you never heat up the system completely.
186:10 as a result of that if you really heat it up, maybe you
186:13 really melt it. So these are three most common um you know,
186:22 that people have for why you can up a continent and not produce a
186:26 lot of magnetism. Questions about No. Right. Um, I'm
186:40 skip on this and I'm gonna start about volcanic margins. So the other
186:45 of marching richard margin is a volcanic . Right? And they are defined
186:49 large volumes of mount. Now I to you the most schematic transact of
186:55 volcanic drifted margin that you can find people using the many books use.
187:00 I'm showing that you're here and then this figure, I have all the
187:04 that show a little bit more So what's going on towards the left
187:08 the continent towards the right is the vertical excesses depths. And this is
187:15 something like 30 km or so Access is a distance towards the left
187:23 , we see a cruised that has since a lot. You see that
187:29 basin sediments fill up the basin, . On the right side of the
187:34 , you can see oceanic crust and in this area, here is an
187:40 . So this is right at the between continental and oceanic little sphere or
187:45 ocean crust. And this is the where people think they see a lot
187:50 evidence for vocalism and magnetism. So so much here, but really this
187:56 the area and people recognize several volcanic or magmatic features on such volcanic
188:04 One is the seaward dipping reflectors that just showed to. So such as
188:09 dipping reflectors, they form again from flows that flow out over the ocean
188:15 and then maybe there's a layer of that's being deposited, another layer of
188:19 flows, etcetera. And so they very characteristic of volcanic margins or volcanic
188:26 margins. Furthermore, which you see on these margins is, you
188:33 of course, new ocean crust that formed. But in this area here
188:38 called new igneous crust here. But will probably describe it slightly different.
188:44 material that you find here, this material that is not really oceanic
188:50 but it is, it is basically material that consists of igneous, so
188:57 magmatic origin. So there's a lot evidence for that as well. It's
189:02 indirect evidence. Right? We've never it, so we don't really know
189:06 there. Um But it's just another of what people think they recognize on
189:12 volcanic Ristic margins. Questions about Right, let's talk about this
189:21 Again, if you are gonna be on a basin on a rift in
189:25 , in your basin is not going be here. Your basin is probably
189:32 to be in this region here. , in that area again, these
189:38 basins are older than the oldest oceanic . They started to form first,
189:45 settlements here will be very old there the continental rift phase and then they
189:51 um blank it'd or covered by sediments are younger and the youngest sediments are
189:58 you know, they can be as as present day. They're all younger
190:02 the oldest ocean crust that you find . Okay, christian to you.
190:10 do these um settlements come from? oldest ones? Where do they come
190:20 ? The erosion during the rifting? . There are constant settlements.
190:26 And then the younger settlements after this was covered with a layer of C
190:32 you know, an ocean mason. younger sediments come from, you
190:36 have a marine origin or maybe they're that come from the continent, turbine
190:42 flow or you know, a refer , that broad sediments down there.
190:48 can find those sediments as well. about this. No, ma'am.
190:57 , go ahead. Yeah. Do oldest elements like also come by like
191:06 breaking off the rocks which are at crust, I mean, which are
191:11 to the mountain regions? Yeah, would be the origin of the oldest
191:15 . So the oldest settlements they are , you know, when this was
191:20 just a continental rift zone, like East African rift for example, those
191:25 , they come from the mountains surrounding rift zone, there's erosion sediment transported
191:31 the roof space and maybe there's a coming by the sediments there, maybe
191:35 a lake forming in the rift zone where all the sediments come from.
191:39 then the younger ones, they're probably in either by a river, a
191:43 delta or stability flow or there are sediments that rain out from the ocean
191:49 . So L. J. For . Yes. All right. Take
191:56 look at the scale again. These be pretty large areas that you're looking
192:01 . So these spaces you find often than one on a rift ID
192:06 right? An old one. And these are fairly large regions.
192:17 let me see what else I'm going talk about. So, I'm gonna
192:24 you this figure. If you google march in google, you may see
192:30 figure like this and I just want explain it to you because this is
192:35 you may do later in your Right towards the left is the continent
192:39 the right is the ocean basin. It says here, thick ocean and
192:46 . So that's the ocean basin and we have continental crust. What is
192:52 here is a sedimentary basin and that be one of those older rift basins
192:58 was formed during the continental rift So these rift basins can be much
193:03 . To be aware of that. , you find here, the seaward
193:11 reflectors, seaward dipping reflectors. Often appreciate them to S. D.
193:17 . S. Or str. Seaward reflectors. Sometimes you see more than
193:22 package. So here's package one here's to just to give you an idea
193:27 what's going on. There's even a three here. So people give them
193:32 names, but it's the same right, lava flows with inter bedded
193:37 layers. Now here he finds something people call a high Philosophy zone.
193:45 we're talking about here are seismic So when waves travel through rocks,
193:52 travel through the rock with a certain and in some rock types, they
193:56 faster than in other rock types. , the rock types where these waves
194:00 fast in are often magnetic. So somebody detects that you assist detects a
194:07 Philosophy song in an environment like the geophysicist may say, oh,
194:12 is probably magmatic material. So we the seaward dipping reflectors which are magnetic
194:19 . You have the high Philosophy which is magnetic material. And
194:23 you can see that here these thin lines, there's a lot of intrusions
194:27 and sales on these margins. So you look here in the sedimentary
194:32 you often find sales there. There being drilled often. Yeah, so
194:39 is just a different figure showing you same Right now. Keep in mind
194:45 following. So this area maybe this basin is 100 million years old,
194:51 forming 100 million years old ago, million years ago and drifting and drifting
194:58 80 million years ago. And this the oldest oceanic curse that we find
195:05 may be the oldest oceanic curse is 40 million years old. This is
195:13 situation that you can often have, have an older rift basin that is
195:18 today located on these rifts margins and , you know, there's younger oceanic
195:25 . Now what happens in between this of the oldest basin and then the
195:30 oceanic crust often there was a phase extension that then resulted into continental
195:36 Yeah, so they can all the basins shorter face of extension and then
195:41 continental breakup. That's what we often . So this extension phase that results
195:46 continent breakers is often short, short less than 20 million years or
195:53 32 more this area here that is . I'm just gonna go back
195:59 Oops, this doesn't really look much . Oops, I have to go
196:08 but I see that at school, ruined it anyways. From here to
196:17 . So that region is often not wide. So it's actually about 50
196:21 or so on the continent margin. may see other reef places, but
196:26 area is not very white, if makes sense. Alright. Um questions
196:37 the structure of these volcanic marches. we move on, ma'am.
196:44 So now I'm going to talk about topic that upsets a lot of earth
196:50 . So, but I'm going to about it because you will hear about
196:54 in your career. So these volcanic that we find for example, here
196:58 the north atlantic, they are often with mental problems and at large igneous
197:10 . So these mental proofs those are proofs of holt material that find a
197:15 from the deep mental towards the Right? And you can imagine that
197:19 mental plu in the rift zone causes lot of mountains. So that makes
197:23 sense. This mantle plumes when they the base of the little sphere they
197:31 something else, they cause a lot melting. So you have enormous amounts
197:36 folk in ism and pragmatism above these plumes. So above mental plumes we
197:43 at the surface of the earth what call large igneous provinces. Those are
197:48 areas on earth where we have a of lava flows for example and they're
197:53 on this map with red. So have one in the U.
197:58 Colombia Flow assaults. We have a one in the northern portion of the
198:04 ocean and many in different other different on earth. And if you compare
198:10 map that shows you the larger can provinces in red with a map of
198:16 volcanic drifted margins and the non volcanic marches. You see there's a large
198:22 . So these volcanic margins, they a large portion of what we call
198:29 large igneous provinces here. For example ones here um maybe this here,
198:37 not 100% sure but there's a relationship them. So there's many earth scientists
198:43 think that the you know the large provinces are formed by mental plumes,
198:48 of material, volcanic margins are formed mental problems as well. So there's
198:55 on it. We don't know whether is true or not, but you
198:58 see this in the literature or So that's the relationship between volcanic margins
199:05 large provinces. Questions about this. right. So we have about 15
199:17 left for today and what I wanted do, I'm just gonna go out
199:20 this power points real quickly and I'm make a new slide here so we
199:28 draw some things and um, let's all the information. So we're gonna
199:38 with continental rifts and then they develop wristed margins. And I'm gonna ask
199:45 of you to, let's start with . When, why are you not
199:52 to explain? Try to explain to of us how continental systems form tectonic
200:03 are drifting towards drifting apart from each . That's when there would be an
200:12 . I mean, that's when we find the starting of the formation of
200:17 continental rich and and afterwards the heat the mantle also will add to
200:25 And the because of the thinning of crust and s here. Uh,
200:33 because of the feeling it just actually it easier to dress the part and
200:37 might be a formation of water bodies something in between. And uh,
200:43 that would be a mid continental rich after the basin is formed,
200:50 So let's start, let's go back the continent rift face. East,
200:54 rift rio grande rift, that's So, if I would ask you
200:59 describe the size of those rifts, would you say? Length with
201:06 Mhm. You can ah meters 4-5 and width depends on the beta,
201:15 the beta is more than the width the ribs, actually larger.
201:21 what's the typical data factor stretching factor a continental? 1.3? And if
201:28 two or more, then it's a wider basin, correct? And it's
201:33 very extended lift Hayden. Um So continental rift zones, what are typical
201:41 of these rift zones? If you at these rift zones, if you
201:44 over the earth in the rift what do you see? Oh,
201:53 , you're rooted at, what stage we talking about, I guess.
202:02 Because I kind of visualize that one that you had with three different
202:09 Um I'm sorry, it's the top of the three. Okay, so
202:15 see depression, you see subsidence? , you might see like marine
202:24 Um like there could be like, could be like a lake in there
202:28 I don't know, it could be water, it could be a
202:34 maybe Falken is um Right, a , you would recognize the rift zone
202:40 because of the normal thoughts that you see? Um Excellent. Um
202:49 for you to question the size of rift zones. The continental rift
202:52 What are we talking about with depth Like 200-300 km I think is
202:59 we said for width. Um Depth just like uh you know, maybe
203:10 km? I don't know, something that. Um was there is there
203:16 3rd 1 I'm missing? Um I'm sure. Yeah, so quickly 1000
203:27 or so with, you know, rift basin can also be 50
203:31 Right, right, So I would probably 50 to 200 kilometers or
203:35 Ok, ok. Except for when are talking about these very right rift
203:40 such as the basin and range then you can talk about 800 kilometers
203:45 so. Yeah, excellence. So sediments in these continental rift zones,
203:50 do they come from? They come the continental crust or maybe um erosion
204:01 the event. And then rivers um , maybe a mountain bell, You
204:12 , there could be Yeah, So there are usually terrestrial sediments,
204:18 some lake sediments that if you can there, if it's a lake or
204:24 question sediments, it can be pretty organic carbon. So they can be
204:28 source rocks. The other rocks that talking about and conglomerates recent stone,
204:37 not a good source rock. So , excellent. And then at one
204:43 in time, maybe we're looking at risk based and it eventually starts to
204:47 up. right, this continental breakup then you're looking at a rift in
204:52 in so this rift in March, , what does it look like in
204:57 , volcanic, non volcanic? It really matter. Pick one mechanism
205:06 you're talking about or the edge of continental drift to the rift, that
205:14 of the continent's okay. So, , it is where I think it
205:22 be a band of a water body the water bodies deposited, uh,
205:28 can have some sediments accumulated through the also. And it actually forms a
205:38 the layers actually form like consecutively with debt. That's what I remember from
205:45 picture you showed. Yeah. So this continent margins, these rifts,
205:51 margins at the larger depths, you still see those, those continental rift
205:57 right there. Still there, the depths these refer patients have been filled
206:01 with sediments on top of these Other sediments have been deposited so often
206:08 continental, you know, rift at , they have kilometers of settlements,
206:13 are big sediment piles that we're looking here. So, the gulf of
206:18 , for example, is a drifted and it has an enormous pile of
206:25 as you may know, it's truly . So, it's more than 10
206:29 , if I'm if I'm correct, truly amazing. Um Hayden, how
206:35 you describe a structure of a rift continent margin, the structure geometry.
206:54 , should I go into detail about of like the subsidence and why it's
207:01 ? That was? Um It's not you're you're it's not when your mantle
207:19 shrinking. Um Actually it is. , I'm trying to visualize the illustration
207:29 . Um Okay let's go. We've this plot now many times. I'm
207:36 to show it so often. This this is gonna be a prominent part
207:40 your final exam, the oral exam here, subsidence, vertical axis.
207:49 personal to access. So I'm gonna another subsidence curve. So this continental
207:56 or rift ID marching subsides curve. does it look like? He would
208:01 to guess rapid subsidence followed by cooling like this. Right. Let's make
208:14 axis here. So I hope you read it millions of years, horizontal
208:30 80 70 60 50 40 30 Right. When I give you this
208:35 ? When did continental breakup occur? . Perfect. Did you did you
208:42 the same answer? Yes. Perfect. Alright, I'm gonna sketch
208:49 curve. I'm gonna tell you it's rift zone, an extension area.
208:59 continental break up occurred but actually it talk because it's just in your life
209:10 local because sketch the other curve Right. Say I give you these
209:19 curves during your final exam because And B. one of them is
209:27 a drifted margin and the other curve often active continental rift zones which is
209:33 Rio grande rift, which one switch the current one which is forming and
209:41 which is actually formed and you can how wide it is? Yeah,
209:47 has cooled down. Right. So has first underground active rifting and then
209:52 phase of cooling down. Would you ? Hayden? Yes ma'am. Let's
209:59 another one that you can get your action. So did we say that
210:04 it was still developing like it was drifting? That's okay. Yeah.
210:08 if you look at the east african or the rio grande rift today,
210:13 looks something like that. Mhm. there is no there is no slow
210:19 of cooling yet because it is you know, it's still it's still
210:25 . Right? So it's just going and you haven't you haven't reached that
210:30 phase of cooling yet. Okay. it be drawn in a way that
210:36 shows, you know, we still a line at you know the present
210:41 . Yeah. So instead of if this is today, it will
210:48 whatever it looks like. Okay. , excellent point Aiden. So if
210:56 line was drawn here, what would mean? Yeah, you had active
211:04 and stopped. It never reached continental . It was just, you
211:09 a rift and at one point in the rift field, Yeah, it's
211:14 forming, its under process. This is still going on because present day
211:20 see that? Yeah, Yeah. All right. Um Did you
211:29 did you say the answer to If we saw something that just stopped
211:34 You know stopped 60 million years And yeah. So what you probably
211:40 see you may see something like this little bit of cooling afterwards. Do
211:44 know what I mean? Okay. what was the reason for like that
211:52 maybe? So when you when you in the crust right it's in the
211:57 little sphere and this is going to down So even the field continental rift
212:02 gonna show and show a little bit that. Okay. Alright. I'm
212:11 give you an honor example. Um see. Um Oh no I'm gonna
212:32 gonna sketch something else. Something Okay come a sketch. Right so
212:44 is a rift margin right? Was and around 40 million years as continental
212:50 and animals slow subsidence after that. I'm gonna call this the tectonic subsides
213:02 which has you know this tectonic part here the cooling part right? The
213:09 part, thermal contraction part. And gonna say that this tectonic subsidence curve
213:17 the result of a tectonic process should drifting. And I'm gonna ask you
213:24 sketch the burial history or the geo of this curve. So the barrier
213:37 jewish history. That was the subsidence that included all ingredients the tectonic
213:44 Right. That was formed by rifting for land based and whatever that creates
213:48 accommodation space and the sediments. So would have more load? It would
213:53 yeah. Yeah. That would be burial history of her three. So
214:03 dash lines are the boreal history of . Yeah it has the effect of
214:08 sediment. What we call the sediment or loading is included. Right?
214:16 this shows you okay, how deep the hole because of the tectonic
214:24 Maybe fletcher of the little sphere or ? And then this tells you what
214:29 happened. We filled them with sediments this is what happened over time
214:36 And then to go from this curve that curve we did back stripping.
214:50 did the last saturday on the board . So you would ask me a
215:03 a few minutes ago and I think I'm trying to I'm trying to remember
215:10 it was but um you know, mistakenly said that it's not when the
215:15 is shrinking and you said it actually um what was that question again?
215:22 after continental breakup, these riffs of , they continue to subside. That's
215:27 of cooling off the mantle. okay. Because I just wasn't in
215:31 right thought process when you asked me question because when I visualize um when
215:37 visualize the subsidence curve like this that a lot of sense to me.
215:42 but I need to be able to you know, recognize that I need
215:46 be using this you know, for particular. So you need to start
215:53 these curves that three D. Picture ? What's going on right? That's
215:59 easy isn't there some initial uplift And before before you start cracking the
216:09 . I mean doesn't it? You because you have the heat that's upwelling
216:13 whatever is there or is that not thing? So I don't believe so
216:18 many people do but I would ask the following say before you form a
216:24 zone, the whole area was uplifted little bit maybe because of a mental
216:29 . Who knows? I'm gonna say you're not gonna see it because that
216:36 have been eroded. Right? Everything a sea level wants to erode
216:43 But wouldn't there be wouldn't there be an erosion a like uh some sort
216:51 irrational boundary that might outline the area up with it may and so they
216:58 not been found. Um Yeah people tried to make those and find
217:04 I could paper deal that that has it that's a few years ago of
217:11 entire continents on earth. And it not been found. And that is
217:17 interesting. So many rift basins form places that have higher topography but it
217:24 also be because origins old mountain ranges a week. Right. So they
217:30 to be higher elevation, they are crust, weaker little sphere and now
217:35 form a mountain and a rift over I mean right, I I get
217:42 whole pre existing weakness thing. But there are places where, you
217:48 where zones of pre existing weaknesses were through pretty old rocks like the Nubian
217:55 or you know through parts of brazil the pan african or resenting it.
218:02 , um it does all and I , you know, I don't
218:06 I'm just wondering because I tend you know, because you showed your
218:12 where you had the little the, know, the rift blocks of the
218:16 bounding fault, you had those uplifted um if those were uplifted, you
218:22 , in your diagram, then they been uplifted in the history of the
218:28 the formation of the whole right like . So those bits and I understand
218:34 why why they're they're preserved because they're they're not big enough structures to deflect
218:42 the mantle there. This crust is enough. The atmosphere and crust is
218:47 speeches, but I mean, they up and so doesn't that sort of
218:53 that initially the rift was uplifted? don't think so. No. So
219:09 I would do if you have energy go over rifts and wristed margins and
219:15 sure you get it the heat, subsidence the history structure. Okay,
219:24 they're spoken Ism So what we're gonna tomorrow. So the in in the
219:31 and 2nd weekend, we talked about land bases. I'm gonna come back
219:35 those tomorrow morning. but we also about atomic basins. I'm gonna come
219:41 to those and there's more types of for earth basins and pull apart basins
219:46 strike slip basins. And we're gonna to them about those tomorrow as
219:51 So tomorrow, at the end of day, all these sedimentary basin
219:56 you will know how they form where form the subsidence history, where the
220:04 come from and the heat. So eventually at the end of tomorrow
220:09 have been through all of these So I would, you know,
220:14 you get these out of your system , if you learn these and you
220:18 over the material again and you remember , it makes tomorrow a much easier
220:25 . So if you have energy tonight go over the risk basis again or
220:30 even the platonic basins, it will you tomorrow. Thinking of starting the
220:39 , sorry, Tomorrow, when are thinking of starting? That's a good
220:44 . When do you guys want to ? So one idea is to start
220:47 8:30. If we're done earlier in day, it's fine. But at
220:51 it gives us enough time. That's with me. Um Yeah, whatever
221:01 guys wanna do. I'm open to too. Anything, anything you decide
221:09 cool. It's really okay with Yeah, it's fine. Okay,
221:15 about we go for 8:30 again? we if we end half an hour
221:19 , it's fine. But you we have to go through that
221:23 Right? So all we have all , three types of sedimentary basins.
221:28 then um tomorrow we're also gonna go patrimony figures. I have many of
221:33 that I want to go over with again. Um So there's there's still
221:37 lot of material for tomorrow. So the end of tomorrow I would like
221:40 be completely done with all the material that next friday we can just have
221:46 refuel session basically. Yeah. And um quick question, have you guys
221:54 writing the patron newspaper yet? I , I've got my abstract and my
222:01 done. Fantastic. That's fantastic. about you just started the introduction
222:10 Okay, it's a good idea. , how do you say that inspiration
222:16 writing can't come on demand? so Dylan and I, we've written
222:21 lot in our lives and I still it if I think um you
222:26 I need to have this done by day, don't do it all the
222:31 day. Because what if that's the that you don't have inspiration for
222:35 Right, so try to put slivers text in your, you know,
222:39 your draft earlier than that. anything you can get in, even
222:45 it's bullet points of what you want tell later or you get the figures
222:49 or whatever. Um start filling that . Okay, Yes, ma'am.
222:55 . And and if you have your decided for your capstone project, you
223:01 start writing stuff for that too. can write productions and data sections and
223:06 like that. Can I ask a of and if if I have two
223:13 questions I think go ahead. so I think I understand hydrocarbon index
223:24 that is I think it's the total , however car carbons over T.
223:30 . C. Right, It's it's ratio of the what's been produced over
223:36 is all possible to be produced times or whatever. But it's okay.
223:42 then what what's it? I can't , I mean I've looked through that
223:47 by the german authors um transformation Is there an easy way to think
223:55 that? Yeah, the easy So how you can think about it
224:02 your head is um what percentage of in your source rock has been transformed
224:13 oil or gas? And so that said to simply write but it is
224:18 good way to think about it. you're you know, if your source
224:22 just starting to mature, your transformation will be very low because only small
224:29 has been trans trans transferred or changed oil. So you first form oil
224:36 then gas right with most carriage in . So you start forming oil.
224:41 some of the long molecules are breaking you form first long long oil
224:48 So that is heavy oil. So your transformation ratio if that number is
224:53 510% you're probably in that very very oil face that's very young oil.
225:02 just started to form your transformational goes . You start to form your your
225:10 molecules start to break into shorter and molecules. And there's a transformation
225:18 You know arrange where you where you molecules that form in that that fall
225:25 the oil. Maybe light oil category are most they're worth most most valuable
225:34 there most valuable oils. So then are maybe at 30-60% or something like
225:40 or 70%. If you go above your your molecules they start to break
225:48 gas sized molecules right, methane, , propane, butane their value is
225:55 less. And then eventually you end with only methane. Sure the shortest
226:01 molecules and methane as you know, not worth a whole lot in today's
226:08 in any market. So that transformation which is considered most optima is when
226:16 would be in the oil or light window. So that would be more
226:22 like 50%. Does that make 10% would be your tools, you
226:30 heavy oil and if you had 95% burned up basically everything transformation ratio is
226:38 about the quality of hydrocarbons being Whereas the the hydro uh hydrocarbon index
226:48 tells you how much of the total . O. C. Has been
226:54 into into hydrocarbon. Is that is the there's some those are directly related
227:02 um you know again when you form the care Children that changes into a
227:08 gas um it that goes around the you know it's not perfect but there's
227:15 order to it, right? So first found the happy oils,
227:19 light oils, gasses, gasses dry . So um that is also in
227:26 sense in the hydrogen index. So hydrogen index, you know it starts
227:30 with a certain value and then as as you start maturing your carriage in
227:36 drops off and um I don't know strong that relation is. But there
227:42 be a similar relation right when it starts to drop off. Yeah I
227:47 I can see that because as you because as as you um let me
227:54 here, let me turn my thing I can see that because as as
228:01 maturing as the whatever you're you're you're down the molecules in in the carriage
228:08 your eating into the total T. . C. So I can see
228:13 they're connected. But the difference is the index just tells you how much
228:20 the petroleum exists relative to the whatever peat and every all the other organic
228:29 . But it's the quality that's covered tr I guess is that is that
228:33 of thinking of it? No. that is that is that is it's
228:40 in our in our everyday wording the is more included in the transformation
228:48 Yeah, because because the hydrogen index doesn't help you that much because there
228:58 be, well I guess it does it's telling you what the ratio
229:02 But I guess the index, you think of it as a probability
229:08 a probability indicator of you know what chances you have of finding whatever.
229:19 , I think I get it Thanks. Those are really important.
229:23 mean tonight is very straightforward. It's the maturity. It's just whatever.
229:27 just pete to whatever lignite whatever. yeah. Okay. Yeah, that's
229:38 . It's pretty cool. I actually really love this material. I can
229:44 and you know a lot about Um This is a really useful lecture
229:48 because I you know what I I yeah this is stuff that I
229:53 know, I'm a gravity Magnetics potential guide. I understand all the regional
229:58 and tectonics and stuff but it's the the I was gonna ask you though
230:04 you don't mind. I'm sorry I to but can you, can you
230:12 you got your mod and the Mackenzie sheer model into, into understanding magmatic
230:22 a magmatic margins. You mean can kind of include it? I mean
230:33 you fiddle with the thicknesses and beta and temperatures too? You can
230:42 So even in you can include this you know where it says the Mackenzie
230:49 flow tap when you click on that got this curve right? It goes
230:53 and down and you can manipulate those of the thickness of the cursed and
230:57 atmosphere. So you can manipulate those . But you can also manipulate the
231:02 estimates for boundary. It's called something mental temperature or so you can manipulate
231:09 into a volcanic margin. If you volcanic margins are halter for example you
231:16 do that, you just increase that A. B. Temperature or
231:21 You would decrease it for a magmatic . Yeah because I can see how
231:26 could trick it into you know you like a beta of one and and
231:34 a tiny very old short rift And then you could put in for
231:42 the mantle thickness. You can put whatever the curie point depth and then
231:48 it a curie temperature at the thing kind of trick it into accepting a
231:53 depth as as a horizon. I could see that but yeah,
232:00 it's very simple. Right? That's literally does top base of the little
232:08 temperature temperature gradients. Um And that's But if you have a basement terrain
232:17 are of different compositions that are have heat production. You can't you can't
232:24 it into, you can't load basement into the model into can you know
232:32 what you do you have when you the basement, you can choose a
232:37 night that's a billion years old. 500 million years old. 150 million
232:41 old. So you can it's already there and you could you could so
232:47 trick it in that sense as Right. So one single basement.
232:52 not you can't put in like terrain in the basement where you have granite
232:58 up against Gavroche or whatever. I think in two dimensional or three
233:03 models, you define all sedimentary layers two dimensions, right? Or three
233:09 . So, the natural variations you put in there. You can put
233:13 in your grid. No. For And you would do it as a
233:18 of age. That's variable that they it likes. So, that's the
233:22 . Right? That younger age would more heat producing than value based on
233:29 age. Yeah. So that's not mean. Okay, but that's still
233:35 very satisfying because You know I you have to know what ages make
233:40 think what heat production values are when is there is heat production station data
233:47 for different terrain that you can OK. All right. I'll stop
233:52 you. Thank you. Okay, you tomorrow morning at 8.30.
233:58 Very good. Sounds good. Thank
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