VideoPoints

• ••• • •• • ••••• • •
GEOL6351-Basin Modeling - Day2 09-24-2022-PM
Help Tour
© Distribution of this video is restricted by its owner
Transcript ×
Auto highlight
Font-size
00:00 do you want to start with? ? It is perfect. Okay,
00:05 hope you had a good break. we ended this morning, we're looking
00:10 at how um the mantle deforms right flow, that creep process. And
00:17 is also, you know, one those creep processes is also how we
00:22 that the lower crust to dr lower the forms. So what we're now
00:26 to talk about is the brutal upper . And I'll come back to the
00:33 crist as well in the coming hour so. So see we have um
00:44 area on earth maybe. Um let's Canada. And at one point in
00:54 , Canada, I'm not gonna sketch but imagine this is Canada. And
00:57 looking from the air at Canada. point in time during one of the
01:04 ice ages, a large portion of was covered with an ice sheet.
01:10 I don't know what it looks Maybe something like this. And this
01:15 the ice sheet. It was covered of Canada at that time. Now
01:23 ice sheet issue probably all know, caused Canada to subside right? And
01:30 after the ice age when the ice has molten away, the surface of
01:35 earth came up in Canada. And the northern us. So that's uh
01:42 . Um First the service going down the influence of this ice sheet and
01:49 the surface coming up again when the sheet was removed. That is called
01:55 behavior of the crust, elastic behavior elastic deformation, elastic behavior or elastic
02:12 . So what does this mean? it's also it's what we something we
02:16 linear elastic behavior. And I explained you in a minute that this
02:27 So what does this mean? So we load the crist written I.
02:36 sheet. So here's the top of crust. Let me make it for
02:44 song, top of the crust. here's our growing ice sheet. Now
02:56 earth chris is going to do is to bend down under the load of
03:03 ice sheet. Now end of the sheet, ice age three and the
03:16 sheet is removed, it starts to away. Maybe a little bit is
03:27 . How does the earth response to ? The cursed bends up and bands
03:37 so much that all the deformation that caused by ice sheet, it's now
03:43 . It's been removed so the crust completely recovered. So this is called
03:51 elastic behavior. It is total recovery the load is removed. Questions so
04:12 right? So I'm gonna go to next slide. So total recovery when
04:18 load is removed, linear elastic I'm gonna sketch a graph here.
04:24 one to access data, vertical access , zero sigma, the notes in
04:33 next rest of today stresses an epsilon notes and the rest of the day
04:42 linear elastic behavior means there's a linear between stress and strength and up.
04:49 removal of the loads. We go to the original situation. Now,
05:00 for in case you forgot stress, , is the force per unit area
05:12 its units are skull to stress. hydrostatic stress. Right? I mean
05:25 think of sigma one sigma two sigma sort of thing. Yeah. So
05:30 not. Yeah. So actually it's next uh so we're gonna talk about
05:38 in a little bit. Principal You mean? Right. Yeah.
05:43 . Yeah. Okay. I'll shut . No, it's okay. So
05:49 other words, Earth's little sphere accursed of them. They behave elasticity following
05:58 elastic behavior. Um When you don't it too much. So loading with
06:05 ice sheet, you know, ice grows slowly. It's not that much
06:09 the slow removal of the ice It's not really spectacular. That results
06:14 elastic behavior elastic behavior. Mean, know, there's a load you perform
06:19 , you remove the loads, it back to its original situation. So
06:26 is when the curse is not stressed much. No, let's move to
06:34 next situation. When stress is are a certain threshold value, then something
06:54 will happen first. We would have elastic behavior. And that looks something
07:10 this. So this was our linear . Right? Nonlinear less behavior.
07:15 more like a um I need to about if I can sketch it.
07:19 like a loop. Do you know I mean? So you remove the
07:23 , it doesn't go back all the to where it dwells It takes a
07:26 class. And then then if the are increased even further we're gonna go
07:33 failure fill your means in the brittle crust. Reform of fault or in
07:43 doctor lower cruise. We have doctored this here this is permanent. Once
07:59 fall the form to falls we can't the falls. Once we have dr
08:04 information we can't undo the doctor the . Yeah. So when the stresses
08:11 low we have elastic deformation. We back to its original remove for example
08:16 ice sheet. If we're gonna go we first enter the norm elastic
08:22 So some of the deformation is permanent eventually we go to failure. So
08:27 in the brutal up across or ductile . And the doctor lower cost questions
08:34 far. No ma'am. Alright. . At low temperatures and pressures.
08:46 temperature and pressure when they are low low relatively. We're in the upper
08:57 and we'll have ritual behavior. We have brittle behavior at larger debts.
09:08 We'll come back to that in a generally when temperature and pressure are
09:15 So in the lower crust for example have dr behavior. So dr behavior
09:26 saw earlier. Right? You may a sheer song but you're not going
09:30 form a fault like a false surface you do in the upper crust.
09:38 I'm first going to focus now on brittle behavior. So what is gonna
09:42 with temperatures and pressures are low. like in the upper part of the
09:46 upper crust brittle behavior. What's gonna one point in time? He said
09:54 um the curse is gonna feel fotos form. When is that going to
09:59 ? It's gonna happen when this is going on. This is the
10:04 I'm just going to remove it because looks horrible, Explain it in a
10:22 1st. Um give you a second copy this equation. So it's a
10:28 one minus sigma three. Largely A greater equal than better times rho
10:36 G times e times one minus Has anybody seen this equation before?
10:53 has a name? I'm gonna give the name. Just so you've seen
10:57 . This is called by ali by law. So by at least fill
11:04 law. I heard something about the knowledge principle. But not this not
11:16 . Alright, so what does this say? Sigma one sigma three.
11:22 maximum and minimum principal stresses, if stresses um exceed the term towards the
11:36 , will form a fault in the . So what is better bad has
11:41 number and the number is different for faults and refers false it strikes,
11:47 falls. So it's a number. for normal faults it's 0.75. I'm
11:52 gonna give you the values that you an idea role here is density of
11:59 crystal rocks. G is gravitational So that's like 9.8 m per second
12:10 right? Z. Its depths. I love that is what we call
12:28 poor fluid factor. Whoops sorry, fluid sector. So what? That
12:39 mean the poor fluid factor is the fluid pressure, divide it by the
12:53 pressure. So what does this situation ? In general it means that when
13:22 in the upper cruise where temperatures are very high that if you um your
13:28 principal stresses exceeds the number towards the , a fault will form in the
13:34 . If you extend the course you form a normal fault. If you
13:37 the cursed, you will form a fold. If you how do you
13:42 the cursed, You will form a fault. Strike slip fault. That's
13:46 it says. So um one I'm I'm gonna I'm gonna do two things
13:53 . The first thing I'm gonna do I'm gonna sketch this graph and then
13:58 gonna come back to one um Let's see. So first of all
14:05 sketch what this looks like. 1st to access Sigma Sigma three,
14:15 Take my well my secret sweet fertile depths. And that's we often indicate
14:22 a Z. Mhm. Now if go back to this equation, you
14:29 that there's a linear relationship ship between and sigma three and this Immigration and
14:35 . So this is gonna be a and this line does something like
14:42 Here's the relationship. So what does tell us? This tells us that
14:49 our sigma one minus sigma three exceed value that is indicated by this
14:56 we form a fault. So we towards the left here. The cursed
15:03 not under any stress. Now we're stress the curves. Maybe we are
15:09 it and it's gonna be stress and and stress more all this time
15:14 it will still have elastic behavior. you would stress. If you would
15:18 that, it would go back to it was originally. Then we're gonna
15:23 close to the curves. And now nonlinear elastic behavior start, then we're
15:29 hit the curve right here at that in time, what will happen will
15:34 a fault fought in the crust. , that's what this relationship means.
15:45 , I'm gonna go back and take look at this equation again. Because
15:49 is important for if you have an in working in the petroleum industry,
15:57 this factor lap Deion, they're right we call the poor fluid factor.
16:00 the poor fluid pressure over the alpha pressure. Now, when we inject
16:08 or C. 02 in a we do that on the high pressures
16:14 we do that to um flush out petroleum that may still be in
16:20 So this is secondary or tertiary So when we do that or for
16:25 when we get rid of waste you know, when when produced water
16:29 wastewater is re injected into the we do that on the high
16:34 So what happens when we do that increase the poor fluid pressure. This
16:39 also, for example, when you to fracture the rock, when you
16:43 the rock and people do a they put the fracking fluids into the
16:48 so they increase the pore fluid So that means that this term love
16:54 will become larger. And if you look at this equation where it is
16:59 this equation, you see that this here towards the right which we call
17:05 youth criterion, it's gonna be crossed lower um differential stresses. You see
17:14 . So in other words, if have a very high pore fluid pressure
17:19 you've been putting freaking fluid in there getting rid of few wastewater or putting
17:25 cl two under high pressure in the , you form faults or faults slip
17:32 more easily. And that is why have induced seismicity and earthquakes. When
17:38 do freaking and when we do, we get rid of waste water,
17:41 example, see that right now let's on again. So this graph shows
17:52 that when this differential stress difference is than around this point, you either
17:57 a new fault or you have get on an existing fault, whatever is
18:03 will happen. Questions so far. then, then I'm gonna move forward
18:14 at larger adepts in the cruise where and pressures are higher at those
18:24 there's a different relationship between the stresses exceed a normal, you know some
18:29 of value and information. And so relationship I'm gonna write down now and
18:36 looks like this. I'm gonna write down. You don't need to learn
18:40 by heart or anything like that but want to give it to you.
18:43 you have an idea. So what see here again in this equation is
18:56 that looks like strain. This is strain rate. There's an epsilon again
19:04 towards the right here you can see stresses again. Now we can rewrite
19:11 equation and then it looks like this sigma one minus sigma three or uh
19:17 , but we just had ecos. here we have again a relationship between
19:47 principles stresses and in this particular case temperature not with death but with
19:56 So what would this relationship, this criterion look like? If we would
20:03 it? I'm gonna do that in next slide. So hers also access
20:07 again have sigma minus sigma three, axis is depth or temperature. We
20:17 know that temperature increases with depth inside earth. Right? So I can
20:20 the vertical access also temperature I'm just make it uh temperature. Sorry,
20:26 gonna make a depth here but it also temperature. All right, So
20:30 I'm gonna sketch this curve. This . The relationship that we just
20:38 Oops, that's this shape. So . Right? Exponential decrease with an
20:49 in temperature or with an increase in . So what does this means that
21:00 we are at large projects in the temperatures and pressures are higher? The
21:05 have again that um elastic behavior phase we're in. Right? However,
21:14 this term is gonna increase and we're gonna be at the point in
21:19 where we're gonna cross that curve. is what we call our youth
21:24 This is what people call that. then we when we hit it,
21:29 gonna have permanent deformation in the upper . That was faulting slip along the
21:34 . In the lower course. That be ductile deformation questions so far,
21:46 gonna go back and let's take a at this um equation and a little
21:50 more detail. So, these are differential stresses. I'm not going to
21:54 about those. An earlier earlier sketch had absalon vs. Sigma.
22:01 I think sigma here an epsilon Absalon would be called strain an
22:12 Absolutely. The dot on top of is train reads stream rings A.
22:23 is a constant. That has a . It's called Adorn constant after somebody
22:28 did experiments in the lab. And a number And this number is called
22:35 power law exponents. And then a for N. is for example 2.3
22:46 three. A number like that. we have here. Q.
22:52 Is the excitation energy. Mhm. here is the gas constant and
23:10 C. Temperature, correct? Anybody an idea what activation energy could mean
23:21 in this context? Um I would the energy required for the molecule to
23:29 from the lower energy level to the energy level. That's what it is
23:33 chemistry. That's also what it is earth science. That's perfect. Remember
23:38 he sketched those crystals. Right? maybe a vacancy and then there's places
23:45 . So it's basically an energy that could see that is needed in order
23:49 this little guy to jump out of comfortable situation and make it over
23:57 Yeah. Excellent. All right. what does this equation tell us?
24:04 equation tells us when dr deformation or deformation may occur. So it's a
24:11 youth criterion. Right. First we elastic information and at one point in
24:16 we reach the youth criterion, there's longer elastic deformation information is not
24:22 Whether it is this jumping and fiscal or doctored information or whether it is
24:29 formation of a fault that we saw the brittle part. Something is gonna
24:34 . That's what the youth criterion So what does this mean? In
24:41 ? Let's make one more sketch. have sigma on minus sigma three.
24:46 then the vertical excesses depths. Now first talked about by Ali's Law.
24:52 linear relationship. I guess it's the criterion from brittle faulting. It looks
24:58 like this, right? And then talked about this Doctor Flow Law,
25:04 one that we were just talking about exponents. And it looked something like
25:10 , correct? Now this steps it's called a ritual dr transition in
25:23 cursed the mojo is somewhere here. what does this graph tells us?
25:34 graph tells us that if we're somewhere the upper crust and the upper crust
25:38 gonna be stressed because of whatever may the loading of a an ice sheet
25:44 some tectonic process. At first we elastic deformation that's all going on
25:51 When stresses exceed a certain threshold we're gonna have permanent deformation. The
25:58 deformation is either gonna be brittle faulting it's gonna be doctor deformation.
26:10 the upper curve is reached is crossed . That's the deformation mechanism. That's
26:16 . So if you look at the crust somewhere in here, say at
26:20 steps, maybe that is five kilometers or so the upper crust is being
26:26 . You see that it is much to reach this this brittle failure curve
26:33 it is to reach the Doctor of curve. So that means that in
26:37 upper crust we have brittle deformation in lower crust. It's a different
26:42 I can extend this Violence Law curve it does something like this in the
26:47 cost. It's a different story when increase our stresses on this lower
26:52 we're first gonna meet the doctor flow . So that's gonna be a failure
26:59 . We're gonna have doctor the We're never gonna get here. You
27:03 that because at that point in time course has dr lee deformed the lower
27:09 . There's not gonna be any faulty so. Questions about that,
27:18 I'm gonna continue below the mojo below crust. We have the mental little
27:24 . This here, it's a it's ductile flow curve for a typical
27:31 grand night crystal material, granite. Mental consists of difference material you may
27:41 or know that's a mental there's a of all opinion. So let's call
27:46 mantle olivine. All of them has different flow law than granite. And
27:55 of the flow low. I don't what it looks like, but maybe
27:57 looks something like this. Oh, doesn't actually. I know by heart
28:04 looks something like this. Now let's a look what we have. Now
28:12 start at the surface we have this nude criterion. The bias least law
28:17 was reached first. Now we get the lower cross in the lower
28:22 we see that the Doctor flow law the one that is reached first.
28:26 see that now we're at the So now we're in the mental in
28:32 mental. We have minerals rich in of in rocks rich in all of
28:38 . Sorry I have to say so granite flow law doesn't really count for
28:43 mental anymore because there's not much granite the mental. So we're now gonna
28:48 to this flow law here. So is it gonna look like? We're
28:52 the mojo if we look at these and we want to see what the
28:57 mechanism is active re reach this brittle first, you see that but then
29:06 we go even deeper than that that maybe this is like the lower part
29:11 the mental atmosphere. We see that hit this all of inflow first.
29:20 makes sense. Right? So let's a look at what our curve looks
29:29 now. So these horizontal lines shouldn't . They're gonna try one more
29:47 So this is called strength curve of little sphere, wrist strength profile and
30:00 because of its shape. Sometimes people about christmas trees because it's kind of
30:08 the shape of half a christmas tree some. Alright, so this is
30:14 strength profile in the first questions about so far. Right? So let's
30:24 one more time from the left. here's the mojo and this linear
30:41 this linear curve that was bilis lower criteria, right? So that is
30:45 brittle deformation. This linear curve is brittle deformation. This curve here was
30:54 dr the information and this curve here for doctor the information or physical
31:01 So if we start at the surface the earth, we first have a
31:05 in which we have brittle the information the upper crust with faulting. Then
31:10 have a layer reducto the information, the lower crust that sometimes people say
31:15 lower crust flows. Then we enter uppermost part of the Mental little sphere
31:21 then we can have again a zone brutal information and then the rest of
31:26 mental little sphere all the way down the core mantle boundary would be like
31:31 a doctor um Doctor or Fiscus curve that. Yeah. Right. So
31:40 I have a question for you, if you look at this figure
31:46 can you say from looking at this where earthquakes occur at what depth
31:52 Earthquakes occur? Yeah, folds create right? When you have slipped on
32:09 folds, that's how you basically start earthquake. So earthquakes are associated with
32:16 . So we find these earthquakes here steps and these steps. So this
32:21 where the earthquakes are earthquakes in the Little sphere are very rare but they
32:27 been observed in some places. literary earthquakes have earthquakes. Now the
32:34 topic that I want to talk to about is strength. So this profile
32:40 towards the right is sometimes called strength of the little sphere. Why would
32:46 name that a strength profile. Where you point to? What are you
33:00 ? The strength profile? Okay. would we call that a stress growth
33:14 you think you know why that is everything towards the left of this
33:27 the little sphere can take without permanent . So remember here towards the left
33:34 have that elastic deformation, right? not whoops, it's not permanent.
33:39 you could say that this curve indicates strength of the little sphere. When
33:45 when you hit that curve, that's you start to break the curse or
33:50 permanent doctor or viscous deformation. So gives you an idea of the strength
33:55 it relates to the information. So why these curves are called strength
34:00 So now I'm gonna sketch several for . So I'm no longer putting the
34:06 in because I think you know by what's on the axis? So here's
34:11 and we're gonna put a second one here. Oops, I'm gonna start
34:22 . Oops, start over, this the first one And I'm gonna do
34:30 2nd 1. I'll make it with . So it's easier to see there's
34:48 curves. Now one the straight The other one like this open
34:52 Which one of these gives you the little sphere, the straight line.
35:05 . So why is that? It's . It's because it is form compared
35:11 the loops. The loops we can't at what point it is having the
35:16 strength. The straight line. The might be like uniform over the
35:25 Not quite. Hayden, I'm gonna it on to you. So your
35:31 was correct. The straight line gives the strongest little sphere or indicates the
35:37 little sphere here. Oh you're Um The first thing that I noticed
35:51 that the brittle strings are the same both curves but the duck calls are
36:01 . That's exactly what's going on. what I try to sketch. So
36:06 we say that this curse represent the of the legislator, give us the
36:12 of wiggle room we have until we permanent information. That's what these curves
36:16 right now let's first follow the solid . For example at these steps here
36:24 solid curve. If that was our sphere it would tell us we can
36:28 all this stress until we have permanent . When we look at this curve
36:34 has these circles we say we can handle this march stress until we have
36:41 deformation. You see that? So one you said it correctly. Um
36:47 is the weaker one and this one stronger. Makes sense for no
36:58 Gonna try one more time. Let's go ahead. So it's it's stronger
37:05 it is a little bit farther from axis, correct? It's stronger because
37:09 further towards the right. So that that you can exert more stresses on
37:14 little sphere before you have permanent Yeah. So remember everything on the
37:20 side of this curve is elastic Right? It's more permanent.
37:27 Um Let's see. Um It's the curve that I was sketch. So
38:00 of these curves is dashed. The ones is so the other one is
38:04 . Which one presents the stronger little ? The solid one or the dashed
38:12 ? You see it? Right? in other words the larger the area
38:17 the curve, the stronger the little . Okay, now let's take a
38:25 at these curves. So what I here and you were exactly right about
38:29 , Hayden, I never changed this law. I kept at the same
38:35 whole time. What I changed was this doctor curve here. Oops.
38:42 this one here and here the I changed this one and I changed
38:46 one. So this curve are related this relationship. He saw it that
38:54 dependent on temperature. So now I'm go move forward. So the first
39:02 gave us this line here and this here, the first temperature profile.
39:08 first geothermal, The second geothermal gave this here and this here. Which
39:19 corresponds to a higher temperature in which corresponds to a lower temperature? Let's
39:26 all of them A. And And be B. Represents a higher
39:36 . Yeah. Um Maybe I should it differently. A or B.
39:53 one which you find in colder little . And which one would you find
39:57 warmer little sphere be? Isn't be like it's a warmer temperature it's reversed
40:11 scholar and A. Is warmer. let me go back to that equation
40:18 soon ruth real quickly. Sorry. T. Is here. It's below
40:24 line. You see that first. . Alright let's go back here.
40:32 when temperatures in that atmosphere are we follow this line. When temperatures
40:39 warmer, we follow this line so colder. And this is warmer.
40:46 the same for here colder, So that means that in places where
40:53 little sphere is colder, that's where little sphere is stronger. You see
41:00 in places where the little sphere is , we follow these dr curves that
41:05 up here and our little our little is actually weaker. So cold corresponds
41:10 strong and warm corresponds to weaker. let's see um Yeah we still have
41:37 right Now. I'm gonna take one for her. So here's the curve
41:49 and by the way for different areas come back to that in several minutes
41:53 looks a little bit different discourse but doesn't really matter. The idea is
41:56 same. So we know now that is brittle deformation. Right? This
42:00 dr this is brittle and this is fiscus. Yeah. Alright. Um
42:11 we talked about that this here towards left of the curve. That's where
42:17 have a list stick information. A with earth where the little street is
42:32 . This curve is gonna look more this. Another place on Earth where
42:41 little sphere is warm. The curve gonna look more like this. This
42:53 is strong. This one this Now when we talk about elastic deformation
43:02 the little sphere, we don't talk a certain layer. You see that
43:07 right? You can have the elastic everywhere. But geologists like to talk
43:14 elastic deformation in the atmosphere in another as well. And that is as
43:19 . We have here, you know top of the course. So this
43:22 earth surface, here's the mojo, the mental little sphere and then below
43:30 is the S. T. No . So this is how we've been
43:37 about the little sphere so far. then we have like a brittle upper
43:41 and a doctor lower crust. So know that by now we'd like some
43:46 in between brittle doctor mojo. Mental sphere, esteem a sphere.
43:53 if you look at a little sphere a whole and you load it,
43:58 that a volcano volcano can be a right? It's extra rocks on top
44:03 the little sphere. So it's a . What we see is what the
44:07 sphere is doing. It's gonna start bend a little bit like this.
44:13 is exaggerated. Right? It's never this. But just to give human
44:16 it's gonna bend under the road and bending under alert how it happens.
44:24 could see it as if as if it is not, but it is
44:30 if we have an elastic plate and loading this elastic plate with a volcano
44:40 ice sheet and mountain range, So it is as if we have
44:45 elastic plate, so we don't really an elastic plate or an elastic layer
44:50 the little sphere. It's just if look at it from afar as a
44:54 , it looks like it behaves as elastic plate. Now, that's elastic
45:02 can have a certain sickness if you're plate is sin, here's our synth
45:09 plates, I'm gonna load it with volcano. Then the elastic plate is
45:15 to the form like this yourself. , no, if our elastic plates
45:26 be thick. So maybe this thick we're gonna load a bit of
45:32 the same volcano, then the elastic would bend like this makes sense,
45:44 No. Yes, ma'am. So other words, this elastic plate has
45:51 sickness, you're sick here, it sin. The sickness of the elastic
46:03 depends on the temperature and the strength , and this is what's going
46:20 If our elastic plate is sick or plate is thick when we have a
46:28 area on the death curve, that be a sick elastic plate. When
46:35 have a small area on the IRv. Oh, now it looks
46:41 that, but you get the We have a sin elastic plate.
46:46 in other words a strong plate. a place that is called and that
46:54 a large elastic thickness. A plate is warm. It's weak and it
47:03 a thin elastic sequence. So again is not it's not when you drill
47:08 the little sphere that you see an layer. So it's not it's like
47:12 whole the whole as a whole how responds elastically to allowed. Makes sense
47:21 no. Yes. Great. Um let me see if there's anything else
47:29 need to look at at the moment we can go to the um You
47:37 one more thing, one more So this thickness of the imaginary elastic
47:44 is a name and it's called the elastic sickness. Where sometimes people call
47:56 maybe the elastic plate sickness. So summarize this. We have our little
48:13 here but it cursed the mental part top of the nastiness. Fear we
48:26 sketch a strength profile through the little . We did it before sigma,
48:31 minus sigma three vertical. We start , we have brittle deformation groups,
48:40 deformation deformation. Here's to mojo. there's more brittle deformation doctored information all
48:49 way down. We call this the curve or strength envelope. Doesn't really
48:58 how you want to call it. that is because on the left side
49:02 the curve um You know the little can handle that, the information,
49:05 ? It's elastic. You take away load. It goes back to how
49:08 used to be this here. This is called what we call the youth
49:15 At that point in time, deformation be permanent because it's either 14 slip
49:21 the fault, doctored information, physical , etc. And then the area
49:27 the curve, that was something about strength of the little sphere. The
49:34 the area, the larger the strength sense. Right. It's like how
49:39 , how much can it handle before permanently deforms. Now, when we
49:48 at this, we saw little earthquakes are here and here. One
49:53 thing I needed to talk about if look at this strength profile where in
50:01 little sphere is the most strength, would be the strongest layer in the
50:10 sphere at um just below the Um You agree? Yeah. All
50:22 . What would be the weakest layer this particular case? In the little
50:27 ? The crest, which part of crust? The upper probably take a
50:37 at the curve. There's a place in the lower most lower crust.
50:45 where its weakest. Yeah. So the little sphere, there's layers that
50:50 stronger and layers that are weaker and you know, that's it's important.
50:58 important for a lot of sedimentary we'll talk more about that later.
51:04 So in this particular case, we say there's a fairly strong layer here
51:09 the midst first. And there's a strong layer in the uppermost part of
51:14 mental atmosphere. And then in this case, we would say,
51:18 the lower most portion of the upper this week, you see that,
51:22 then everything actually below here is weak well. So, um I didn't
51:29 this curve very precisely. If it have been more precisely than this,
51:35 be more something like this. And you see where you're at the base
51:40 the little sphere here, you basically lose all the strength and that is
51:46 base of what we call the little plate, or the tectonic plate.
51:50 see that under it, there's very strength beneath. There's very little strength
51:57 . So the S tina sphere is weak layer. All right. The
52:06 thing we saw is that um everything the left of the curve is elastic
52:12 deformation. And then the area under curve gives you an idea of how
52:18 the little sphere is and how thick elastic plate sicknesses. So, if
52:24 area under this curve is very we're talking about cold little sphere,
52:29 talking about thick lettuce. Fear, thinking about talking about a thick large
52:35 sickness. If the area under this is very small, we're talking about
52:39 worm, little sphere, weak little and thin elastic thickness of the
52:48 All right, then one more thing we talked about temperature if we would
52:54 up this little sphere, The bible law, you know that forcing youth
53:00 that doesn't change. It wasn't dependent temperature. So it's not gonna
53:04 But the curves that are gonna change these ones here the exponential that were
53:10 dependent on temperature. Those ones are change if temperatures go down in the
53:16 sphere, so that this for cools , this curves curves moves down and
53:23 one moves down if temperatures go up a little sphere, these curves move
53:32 when the curves move up, the sphere becomes weaker. You have a
53:37 little sphere, it's harder, it's when the temperatures go down, your
53:42 sphere becomes stronger, so colder. sphere is stronger. Yeah, So
53:47 called strong worm and weak. It's and stronger together, worm and weak
53:55 together And I called as strong goes a large elastic thickness of the plate
54:04 warm and we go with a small thickness of the plate. Questions about
54:20 , No ma'am. Alright, so we are ready to start, What's
54:29 difference between creme brulee and jelly Alright, so what they was asking
54:38 when you go further in your you may see those terms,
54:41 it looks like they are saying something , but a lot of geologists say
54:46 things jelly sandwich, what's the jelly ? It's a slice of bread jelly
54:52 the middle and another slice of The slice of bread is strong.
54:58 jelly in the middle is weak. there's another slice of bread below.
55:03 take a look at the strength We have a stronger layer here,
55:08 weak layer here and strong layer So sometimes people name this strength
55:17 uh what is it? Rich strength profile. This is what they
55:24 with it strongly strong. I just handout. It's like when the temperature
55:34 , the elasticity of uh material is to increase, right? Like
55:42 Well, but that's not. It . But that's not what I'm talking
55:46 here. So, we're here, taking back, we're taking entire entire
55:51 sphere plates as a whole. When heat plates, it's gonna become weaker
56:00 weaker plate. Sinner elastic plate. that make sense? So maybe it
56:08 the same as what you said, . Okay, I'm sorry.
56:20 go ahead. No, I don't if you are talking about this.
56:26 question about so that there is a amongst gene analysis of the jelly sandwich
56:33 the creme brulee. So, like creme brulee. Those folks think that
56:41 strength of the litmus fear is focused in the crust. Am I right
56:46 not any other mental? Let's talk it because this is important for
56:54 So we can talk about it by slow our doctor flolo, your simone
57:09 , or this curve continues. So it picks up here and then
57:15 does something like this, right? maybe even that we correct, make
57:22 , let's make it more extreme. here's the mojo, we never reached
57:28 doctor branch again because here in comes second doctor curve and this is the
57:35 curve. Yeah, I mean I , this is possible. You can
57:45 this, when would you have You could have that in like beneath
57:51 great basin where you have a really , it's really hot and the crust
57:56 , it's very thin even though the Basin is the Great Basin is most
58:00 most of Nevada. And the, know it's even though the whole region
58:07 very elevated, The crust is only km thick in some places and so
58:14 . And if you put the magnet like flat. So this is that's
58:19 idea for that. But I gotta that that I mean you know there
58:25 , there are only like five rift on the planet that are wide like
58:31 . Um Like the great basin. sense is that just, I mean
58:37 got creighton's floating around since our key time. If this if the creme
58:45 , I hope everyone knows what the brulee is. We've had some of
58:54 have had that dessert. Yeah, just I'm just hoping everyone had
58:59 Yeah. So that's the only reason brought it up because it's, it
59:02 a discussion that people have when they about these yield strength envelopes and um
59:09 sort of ideas. So I'll shut what we're gonna do after the break
59:15 we're gonna look at um a series these strength profiles for different tectonic provinces
59:21 earth. So the one we've been about this one here, that's the
59:25 one. If you explain it to that's what you would do. But
59:29 for different places on earth they look . Right? It's different for the
59:35 than it is for the Great It's different for a creatine. You
59:39 Canada. It's very different from between and um whatever. Um maybe the
59:47 grab in europe or in the North grab. So from place to place
59:51 very different. So we're gonna talk that after the break but it's it's
59:58 good point um deal. And the is is that if you understand how
60:04 build such a strength profile that it's know from bailey's law, the doctor
60:09 things like that. That and that one here is dependent on temperature.
60:14 also gives you a very good idea um what could affect the shape of
60:20 strength profile. Right? It's usually . So yeah. Before just having
60:27 break. So the thing I just about the temperature and the elasticity.
60:33 not like I'm a little bit confused the warmer having the small elastic thickness
60:42 the cooler. Having a longer elastic . No, it's it's the other
60:47 around. So, warm means weak the earth means thin elastic late.
61:02 , yeah. So this example where had the thin plates and then loading
61:07 a volcano and it does something like that goes back to warm story.
61:14 cold story is strongly to sphere thick plates. So it doesn't deform easily
61:32 the cold compared to the woman, . Okay, it looks very
61:37 Don't you think so? Yeah. this is actually, we're gonna talk
61:42 this after the break. This is foreland basins and flexible basins form.
61:47 so we're gonna talk about that So let's see it is two minutes
61:54 . So what I suggest is that have a 10 minute break before we
61:59 on with the foreland basins and then just just gonna be foreland basins um
62:05 the rest of the afternoon. ma'am. Alright, we'll see you
62:12 10 minutes already. Perfect. Thanks your time. Okay. four land
62:33 . So foreland basins are flexible basins that means that are caused by fleck
62:44 of the little sphere and that happens the little sphere is being loaded.
62:50 foreland basins, they form next to ranges. Or 4th 1st Bells.
62:56 for example, on both sides of rocky mountains, we find foreland basins
63:01 the south side of the Himalayas. find foreland basins, north side of
63:04 alps etcetera. Yeah. So that's type of basin we're gonna talk about
63:10 and then a little bit, I'm go to the power point to give
63:13 illustrations. But now let's just start some basics. Alright, if this
63:23 our little sphere and we're gonna load little sphere with a mountain range,
63:33 here's our mountain range, folks. bound what the industry is gonna
63:37 It's gonna bend or flex under this and it's bending or flexing. Looks
63:44 like this. And I'm just gonna , I'm I'm gonna accelerate it.
63:54 This is accelerated so advance and advance such a way that we form a
64:01 deep basin here and then there's something a boot which as you can
64:11 And then here in the back there's of a depression and people call that
64:15 back boot. And then towards here going on. So this is what
64:22 looks like. So in other we load an elastic plate, we
64:28 a deep basin here, approach here back booth here and then we are
64:34 the only formed region. So this deformation of an elastic plate is described
64:42 what we call the flexible equation flexible . I'm just gonna give it to
64:53 . And then later we'll talk about in a little bit more detail.
64:58 you don't need to know this factual by heart, but you need to
65:03 it. So describe the different So the only thing we're gonna look
65:22 now and then the rest of the we're going to look at more detail
65:26 is gonna look at the fact that is 1/4 order differential equation. You
65:31 that? And the fourth all this equation. The forms in the way
65:37 I just showed you. So, is the loads on the elastic plates
65:42 the loads can be again, a range or large volcanic system. The
65:49 has this shape? Does that make ? If this were a second order
65:57 equation, the deformation would have this , but that's not what it
66:02 This is what it is. It's order differential equation that describes deflection of
66:10 an elastic plate. So that's what gonna talk about next. So,
66:15 gonna go out of this power point quickly and then I'm gonna start the
66:23 power point. Then we're gonna talk for that base. Let me see
66:39 I am here. So sure. , you have this power points,
66:59 ? So, we just talked about behavior before the break. So,
67:03 a lot of evidence of elastic behavior the little sphere on earth. And
67:08 example, is loading of the little of the crystal ice sheets. What's
67:13 in northern europe here, look Looking at a map of Scandinavia. And
67:17 happens, for example, in And now now we're no longer in
67:20 ice age, the ice sheet is away. And what we see as
67:25 response is that the cruise comes it moves back up again and what
67:30 see in this map here, towards right is the uplift rate in mm
67:35 year. So the last ice age year was I think 10,000 years ago
67:41 so. So at the moment, part of Scandinavia is coming up with
67:47 a centimeter per year. Right, you may have heard of this as
67:55 . So underneath Hawaii Hawaii is a of large volcanoes on the pacific
68:02 Right? Those volcanoes acts as a on the pacific plate and they banned
68:06 pacific plate in a similar way that occurs in different locations. So that
68:12 shown here. So, you see in the center Hawaii, the
68:17 And then um let's see here, see the banding of the plate,
68:25 see that and you may wonder why this coming up here? And this
68:29 coming up here. That is just underneath Hawaii is a mental cruel and
68:34 causes dynamic uplift and thermo uplift of surface and then superimposed on that is
68:39 flexible of information. Now, let's about foreland basins. So foreland basins
68:46 next to mountain ranges from the same . The mountain range acts as a
68:51 on the cursed or on the load the little sphere and as a result
68:55 that, the little will start to and you form a sedimentary basin in
68:59 Himalayan foreland basin is an example. the Himalayan foreland basin is located here
69:06 northern India and it's the foreland basin formed on their influence of the load
69:13 by the Himalayas here. And as see when you look at this foreland
69:21 , you see that it actually follows entire length of this origin right of
69:27 Himalayas. So this foreland basins can very elongated in shape and in this
69:33 case this foreland basin is also fairly . It's not 1000 kilometers but it
69:40 this hundreds of kilometers wide. All right. So we talked about
69:49 elastic plates earlier today and what I to do is go with you over
69:56 couple of strength profiles and calculated for areas on earth. And you can
70:02 some of those calculations here. So you see the the curve is a
70:08 bit different from what I sketched on board and it's just because on the
70:11 are trying to keep things different. simple. But here this for example
70:17 is the bilis law, the brittle and he can clearly recognize that exponent
70:26 , the temperature dependence Doctor or fiscus now. So here are shown strength
70:33 from different areas on birth. So let's take a look at this one
70:41 , the left upper one. So we can see clearly an upper
70:45 a brittle upper crust and a doctor crust. Just as we discussed before
70:50 break? Here's the mobile 40 kilometer , A rather normal left. And
70:56 here we can see a strong upper in the mental little sphere. So
71:02 upper mental atmospheric layer. This is similar to what we talked about
71:07 Now let's go to the one below . So here we can see again
71:11 brittle upper first. It looks very to what you've seen below. But
71:16 in this particular case the mojo is a 40 kilometer steps but it's much
71:21 and such a deeper mojo you may underneath a mountain range such as the
71:27 or the endless or the Himalayas. that has a big influence on this
71:36 envelope or on the strength of the sphere. You can see now that
71:40 have a very thick and weak lower and that we have a very thin
71:46 layer in the mental little sphere. see that So underneath mountain ranges,
71:52 places where we have mountain ranges, little sphere itself is weaker than in
71:57 locations. So we have a strong normal upper crust, we have a
72:01 weak lower crust, then we have thin upper mental layer, upper
72:06 fair layer and then the rest of mental industry is fairly weak. Let's
72:13 a look at this one here. any idea where that one could be
72:20 what area on earth that one could from? Uh huh there's really strong
72:38 strength, but hardly any got those . Um is it any volcanic
72:50 No, because the volcanic area would halt. Right, so this
73:05 this is from a creighton. So ons. Are these old strong course
73:13 the continents? A little first you see the mobile is at 40
73:18 depth, so a normal chris Right. Nothing weird going on.
73:23 so I think this could be a court um which means very little doctor
73:28 information as you know the state um strong overall, very strong little
73:34 I would think it could be a . Yeah, So this would be
73:41 , a normal area anywhere maybe in rift zone or anywhere else on
73:48 Not too old. Little sphere this would be in a mountain range
73:53 I would think. And this here be in a creighton. Now,
73:59 idea what this could be? Let ask. Are you here?
74:08 I'm here. So let's see it's upper mantle, but a weaker upper
74:17 . So Uh huh. Let me , I don't know. I mean
74:29 me it seems like a combination of The 1st 2 on the left.
74:35 these are these all basins or just anywhere anywhere? I don't know
74:44 Why does it have three? So Oh um this is this is over
74:51 zone Could be so what you're looking . So the mole is shown
74:56 right, rather deep, 60 But what they're indicating here is that
75:03 have to doctor flows for the So could be a region where maybe there
75:13 a very different composition of the of upper or a bit. I mean
75:23 know, it looks like it's like why it's like something's layered there.
75:28 know? I would think that as . Yeah. Right, let's move
75:36 . So we've actually been here So if we load the little
75:40 the elastic plates with some kind of and unload again can be a volcano
75:45 a mountain range. What we see that the little sphere behaves elastically for
75:50 of hundreds of millions of years. this is what it looks like.
75:53 have an elastic plate with the the load is on the elastic
75:58 deflects or flexes the elastic plate. then the space that's being created can
76:03 filled in with sediments for with So what is the elastic place?
76:10 elastic plate is not simple. The sphere, we saw that.
76:14 let's take places like an imaginary plate that can be thicker in some
76:20 And sinner in other places, a elastic plate thicknesses between say 30 and
76:27 km or so. So 80 km high and 10 km is long.
76:33 gives you an idea of what we're about here. So it's not like
76:36 in one layer within the little sphere it's more like as a whole the
76:41 sphere behaves as an elastic place. what can the load be? So
76:46 load can be again a mountain so mountains or volcanoes for example.
76:57 also if you have a thick layer sediments you can imagine that could also
77:02 a load. So a load is everything else that that that is leaning
77:09 the crust, that will be a . Alright so bending of an elastic
77:17 is called deflection. So sometimes we about bending of the little sphere but
77:22 we also talk about deflection of the sphere. So I'm just gonna put
77:27 word here. So you um so know that it exists. And then
77:31 we have the equation for the deflection an elastic plate. So this is
77:37 an elastic plate. And here's the the equation and we're gonna go over
77:44 in the next few steps and let's give it a start here, start
77:49 one term. So deflection is So the term W here and w
77:56 describes the deflection. So the the banding of the little sphere.
78:02 that is shown here with this curve . So this curve, the dash
78:06 , sorry, the solid line I to say that's the deflection of the
78:11 sphere. Next term in this um . If we're gonna take a look
78:18 now is Q. X. X. Is the load. So
78:25 mountain range of volcano. And the is described as a function of
78:32 So the load could be um you , I'm gonna sketch it in
78:36 Maybe a large system of volcanoes for , it's a function of X.
78:44 then it has this term here. m minus roll film. So romans
78:56 M sense for mental and Phil stands everything that could fill in this space
79:04 . So there could be sediments. Mother and G again is gravitational
79:14 Just that we saw before. Reputational . So what does this mean
79:25 This term here means um if you a load on the the little tree
79:31 the crust like that, that um plate is not gonna fall into the
79:39 , below the mantle, below the fears pushing back right? And so
79:43 kind of we call can call it restoring force and this restoring force is
79:49 on the density difference between the material and and how we feel in the
79:57 basis. Q. Here was the acting on the plate, vertical
80:03 And then w again is the deflection the plate. Now there's one term
80:08 the left here. One parameter that haven't talked about yet. And that
80:14 the and I'm going to talk about much more. So here's the equation
80:19 , d here is called what we the rigidity of the plate. The
80:27 rigidity of the plate. That is to reflection. If you have a
80:33 strong called elastic plate it is going be very resistant to the formation.
80:40 you have a much thinner warmer elastic and you put a load on
80:44 it's going to be for much more . That is described by this
80:48 D. So d. Again, rigidity and the consists of several um
80:55 You know the several components that are that are gonna go in this lecture
81:00 of the plate. The first one capital. E. And is the
81:05 smart Alice. The second one is person's ratio. So young small delis
81:11 persons racial go in there. And we also have a term called
81:17 H. To the power three. that is the sickness of the elastic
81:21 . So again Young's model is and ratio. And the sickness of the
81:26 plate. Well the young list and . They are. And you remember
81:33 remember that from a different class. are often called the elastic parameters.
81:44 they tell you something about how how elastic plate response to a load.
81:53 it's called elastic parameters. Young small and prosperous racial questions so far
82:05 So you see here this relationship between flexion rigidity of a plate and the
82:12 of the plate actually two to the three. So what does this
82:16 This means that if we're dealing with thick elastic plate that this thick elastic
82:23 is gonna be very rigid. Very very resistant to deformation. On the
82:31 hand, when we're sitting when we're with a sin elastic plate hot plate
82:37 that point in time. H here small and we're dealing with a plate
82:41 low rigidity to deformation. So this will reform more easily. So if
82:46 gonna load that sick plate and the plate with a volcano, we see
82:53 the sick plate, words to write start to deform. But the information
82:57 difficult. So in practice that means there's a little bit of bending but
83:04 a much larger area. You see and in the case of the thin
83:10 here towards the left, you see there's gonna be a lot of bending
83:16 over a much smaller area. Yeah sick plates will result in deformation over
83:25 large area. So the wavelength slapped of the deformation is gonna be
83:31 Thin plates is gonna be deformation over much smaller area. So the wavelength
83:38 out of the deformation is going to much smaller. But you also see
83:43 if your plate is richard, if elastic plate thicknesses, high plate is
83:48 on the plate is richard that you you your deformation as a much smaller
83:55 . You see that in this particular you're deformation has a much larger
84:02 So there's a difference between these two that is actually really important for for
84:08 basins and more about this in a bit. Okay, so Q.
84:13 . Is the loads downward force per downwards force per unit area? It
84:23 the thickness of the elastic plates role the density of the mental and refills
84:29 density of the inflow material. So are our settlements that go into the
84:33 basin? So flex your resistance flex your rigidity again, is the
84:40 to bending? This is described by parameter D Right, so how thick
84:49 the elastic little sphere? This is on where we are on earth.
84:55 the elastic little sphere thickness or elastic sickness, we appreciate. So here
85:02 cold age. In other studies, may see it abbreviated to E E
85:08 . Effective elastic thickness of the little , or for example to T.
85:14 . The effective effective thickness plate thickness the little sphere. So all three
85:20 you can find in um in different . All right, so how's the
85:31 sphere? Um This is an older that I'm showing you here of an
85:37 study in which the thickness of the little fear of europe was being calculated
85:43 you see it on the map towards right. So the colors give you
85:47 idea of the thickness and here the elastic thickness is appreciated with capital
85:54 And then on the score E Now a look everywhere where we had these
86:01 crate, als in europe. So the the the eastern side especially we
86:06 that the effective effective elastic thickness is like 70 kilometers and up In other
86:14 in Europe where there has been more deformation. Recently we see that the
86:19 of plate thickness can be as little 10 km or sometimes even smaller than
86:25 . And that is especially the case and also here in the Mediterranean.
86:32 that gives you a pretty good idea how the plates thickness varies from place
86:37 place and how quickly it may vary place to place. Questions so
86:45 No ma'am. All right then, move on here. I'm showing you
86:51 fixture and map of the earth in scientists have plotted the effective plate thickness
86:57 they've calculated for the different continents. what you see on this map in
87:02 blue blue colors here indicates the thick that we find that thick elastic little
87:10 . There we are, where we in Accra tonic, old central portions
87:14 the continents. So this part of here in northern America, the core
87:20 south America and much of the core europe and some of the core of
87:27 . Also, what you can see that the is that the elastic thickness
87:31 much smaller in places where we have lot of tectonics going on the western
87:36 . S. For example the mediterranean , big chunks of asia. Alright
87:49 this is really important to remember. that's why I'm listening as here thick
87:54 plates corresponds to old tectonic provinces on . So called sick little sphere of
88:00 continent's sin elastic plates corresponds to younger provinces. On earth rift zones for
88:08 in young mountain range. So make that you remember this. Okay right
88:16 your rigidity. The we saw that is the equation for the Flexeril rigidity
88:21 the elastic plate. So it gives an idea of how easy it is
88:25 the place to deform larger rigidity means rigid resistant to the information. Smaller
88:33 means more easily deformed the question to . So I think you would understand
88:40 that this lecture rigidity varies from place place on earth, correct? How
88:46 does it ferry? And why does vary from place to place on
88:57 Um Different temperatures and brittle and ductile . Yeah different temperatures, different
89:05 Whatever else is going on changes that next question, elasticity also contribute to
89:16 change in the originality. They're directly . Right? If you have a
89:22 elastic plate, your age is large your flexion, rigidity will be
89:29 So they're directly related. Yeah. good points. Yeah. So question
89:34 expect your rigidity change over time. . I would think so what needs
89:45 change for it to change? So the right answer. What needs to
89:51 . Um Well like we mentioned temperature and depth. I feel like those
89:58 change exactly. They can change. . Yeah. So if an original
90:04 tectonic lee active or starts to rift a mental plume comes up, everything
90:11 will change that. Yeah. Alright. Let's go to the foreland
90:17 . We have now enough background information start talking about these basins. So
90:23 give it a start. Alright. picture you may have seen in your
90:27 program at one point in time. are we looking at here? We're
90:31 at sub ducting oceanic atmosphere. It's from here down. So subjecting oceanic
90:37 and this oceanic atmosphere is dragging with , a continent that we see here
90:43 the other side of the subscription zone the collision zone. We also have
90:47 continent towards the right now our two collide which you know if you're gonna
90:53 then collision or mountains or mountain range the Himalayas are an example of
90:59 Yeah, so coalitional mountain range, collision of mountain range that they form
91:04 crust for is substantially you can see here they form these thrust. There's
91:09 lot of information going on the crist sickened, right? You can see
91:14 here, high topography, if you into the deeper into the little
91:18 you see that there's crystal thickening at base as well. So we're now
91:22 with a thick crisp and all It's gonna act as a load on
91:30 little sphere. So now we know gonna happen when we have a load
91:36 on the latest fear, what is little sphere going to do? Um
91:44 gonna dip school and band, Yeah. So, on the influence
91:51 this load, this little bit of will start to bend. It's not
91:55 shown here in the figure clearly, it will happen. So this
92:02 there will be a depression here that be filled up with sediments and the
92:07 on this side here. You see . So, in practice, what
92:12 means is that we're gonna form a on this side of the mountain range
92:17 we're gonna form a basin on that of the mountain range and these for
92:22 basins that are formed here, they called Flexeril basins. And because there
92:30 located what you see here next to fault, first belt, we call
92:36 foreland basins there in the four lands that fault. First belt, in
92:40 four lands of that mountain range. , not important for this class,
92:46 you may see it in the literature one point in time, is whether
92:50 foreland basin is located on this side the mountain range or that side of
92:54 mountain range, it matters in the , they have different names.
92:58 if the foreland basin, if you're at the foreland basin that is located
93:03 the plate that is going down, call it a peripheral foreland basin.
93:09 you're foreland basin, if you're looking the foreland basin that is located on
93:13 plate that is not going down, it is on top of the upper
93:16 . We call it a retro arc basin. So peripheral foreland basin and
93:21 arc foreland basin. So for the this course it doesn't matter and you
93:28 need to know those words, but just want to give it to you
93:30 case you need it at some point time. Okay, so in this
93:35 case we're gonna have a foreland basin and we're gonna have a foreland basin
93:43 . So it's the peripheral one which the like facing towards however, his
93:50 is the at the back of the of the point of view and the
93:55 of the starting. Yeah, let tell you if that's a really good
93:59 So I have to say sometimes in a little bit confused on who names
94:04 and why? So what I So that's a really good question.
94:09 . So what I understand is um it says Mark. Right? So
94:16 we have all the little sphere. this case of India, although she
94:20 get sphere subjected under the to it's it's a collision, it's a continent
94:33 closure instead of oceanic crust subduction beneath continent where you would have a four
94:38 in a four land with a you have continent on both sides.
94:45 yeah, so the retro rock for is over the slab as as with
94:51 subduction and the peripheral for land is the four arc would be if this
94:57 oceanic plate. That's correct. So was gonna explain the word ark.
95:05 the words are comes here from magmatic . So this used to be a
95:09 zone with oceanic little sphere, you the melting here, the magma moves
95:13 and you would form these volcanoes Right? The volcanic arc. So
95:18 one that's one that's that explains part that name. It's on the side
95:24 when this used to be a subduction , that arc used to be
95:29 Thank you. So deals explanation is correct. And um I don't
95:35 there's many terms, this is another . It doesn't matter for the physics
95:41 us much. It could, it a little bit, but not not
95:45 for us to um to really be about. It's not really standardized.
95:50 right, I mean, but typically when it's ocean continent, it's always
95:57 subduction. And you know, you for but when it's a continent continent
96:03 , they always call it a I mean it's quite, I don't
96:06 always but it's it seems to be terminology that people use, I
96:12 Yeah, correct. So exactly. this at the moment that you have
96:18 continent here and the continent there, call it a continent continent collision zone
96:24 in time when you had oceanic little going down, you called it a
96:29 zone. So for us, what now is that at this point in
96:34 we have this large mountain range. is a huge load on the little
96:40 on the cursed. And as a of that, we're gonna have that
96:43 bending. Right? We're gonna form , flexible basins that are called foreland
96:51 . Right? So this is communicate place that we were just looking at
96:59 . The 4th first belt here and on both sides we form a foreland
97:07 . We've seen this already. We've this already. So, what I'm
97:12 here is a detailed, more detailed section through such a foreland basin.
97:19 of all, we go back and you where the cross section is.
97:23 , this looks better. Alright, section, It's from around here to
97:36 Yeah, this part is gonna be a vertical cross section through. This
97:42 is gonna be shown on this So let's go here. Here we
97:47 . Towards the left is the Fox belt that could be the Himalayas towards
97:55 right is the plate interior in between where the foreland basin forms. Now
98:06 foreland basin is not simple, not simple, like what I drew
98:12 Right? It's not, you here's your load. Well, this
98:15 the foreland basin, there's of course more structure related to that and that
98:19 shown here is commodity. So let's a look at this. This part
98:25 this year is sediment infill of the basin. Little bit delayed. This
98:35 is the deepest part of the Foreign troops and it's called the four
98:41 The four deep is what you in terms when you would sketch it,
98:46 would call that your foreland basin. the four deep. It's the deepest
98:50 of the foreland basin. Towards the of that. We have an area
98:56 we call the four books. So this was 1/4 order differential equation where
99:02 have a deep basin where the load then a little bit of a
99:08 that's the four books. And then have a little bit of a depression
99:13 , which is, sorry, which the back branch there. So for
99:20 , for butch and back broach the deep, that is the real,
99:25 deep sedimentary basin and the sedimentary basin be kilometers deep. So you can
99:31 have five km of sediments there just give you an idea. Yes,
99:36 rather deep basins the next to it four built that is, that is
99:42 up a little bit, but that not much. Four boetsch could be
99:48 m per, So keeps doing Yeah, so four boats could be
99:55 m high. The back boot is smaller than that in in amplitudes,
100:01 may be only 10 m deep or now towards the left, we have
100:07 wedge top and the wedge top that part of the basin that is located
100:15 the toe of that false first So that faults are spelled as you
100:20 continent continent collision at fault for spelled to grow and it grows sight words
100:25 it has these two, those that moving forward on top of those
100:30 A wedge top basin could form so the wedge top, the four
100:36 the four broach and the back Together you call that a foreland basin
100:41 . Now from the left of this towards the right of this figure,
100:46 whole system is easily 500 km or , depends of course on how strong
100:52 plate, is but that would be very normal um very normal width of
100:59 foreland basin. Yes. So the deep, five km deep, seven
101:05 deep, something like that. good size basins. The four broach
101:11 small, the back broach is almost existent. Where do the sediments come
101:19 that end up in this foreland basin ? On the register of the four
101:24 and the four votes where do these come from? They are from the
101:30 of the rocks and through the mountains the rivers they just transport correct.
101:37 which rocks weather here sedimentary rooms? , possible happening from the fold.
101:50 Yeah, most sediments will come from . The false first belt.
101:57 Because the false first belt is gonna up and bigger think about the ALps
102:02 europe, the Himalayas. That's going become a large mountain range and then
102:08 will occur, erosion will occur, will be transported towards that foreland basin
102:14 that's where they end up. Sometimes foreign and basins may also receive sediments
102:20 the other side of the system. from the right there, oops from
102:26 right the back broach area or beyond back porch area. And what we'll
102:31 is that sometimes these foreland basins are on the water so they can be
102:38 under basically in the sea marine And then of course you may also
102:44 marine sediments Shiels um you know marine etcetera. L Gay that rained down
102:51 come to the ocean floor. So may happen as well. All
102:58 So what I've sketched here very is the same situation towards the
103:04 We have the loads which is the thrust spells. Then you can see
103:07 plate that is being formed. We a thick sediment infill in the yellow
103:13 towards the left and we have a bit of a bush. Now,
103:19 going on, for example, in case of India which is still colliding
103:24 Asia. Is that this full thrust is still growing and when it's growing
103:30 grows towards the right here in this . So this would be India India
103:42 still moving in the northwest direction towards . Yeah, so this system continues
103:50 provide its continues to converge and as result of that this load will continue
103:58 grow. It will move towards the with respect to the to the indian
104:04 and this entire foreland basin system will towards the right as well. And
104:12 sounds maybe a little bit vague but it's really important for the basin
104:18 and I'm gonna explain it to you after the break, what I suggest
104:24 that we have a short break 5 10 minutes or so and then we're
104:28 look at that aspect of foreign and . Okay, sounds good.
104:34 I'm gonna stop sharing and I'll see in a few minutes. Yes,
104:43 . Great. Right, So this where we ended our So because convergence
104:49 continues, we have a whole period geologic time in which this 4th 1st
104:54 starts continues to grow. So let's a look at the India example.
105:00 India starts, started in the right, and moved in a northward
105:06 and eventually started about 20 million years or so. I started to collide
105:12 Asia. Now, India is still northward. So this collision is still
105:18 as of today, it is still . So that means in practice if
105:23 are the Himalayas that are being formed a result of that collision and this
105:27 is India, it means it means practice that this full trust belt continues
105:34 grow and how these spells grow is form like a new, you know
105:40 here, if you know what I ? Yes, so they continue to
105:45 not only upwards but also outwards side . Now this means the following.
105:51 , let me go one back so take a look at the left side
105:57 that fault for spelled We have the here, the Himalayas, they act
106:03 a load on the indian plate. indian plate, the forms something like
106:10 . This here would be the foreland that is located here here. And
106:17 is the Himalayan foreland basin. So a Himalayan foreland basins, foreland basin
106:27 located on top of India, south the mountains here we have the brooch
106:34 little bit more about that later and here we have the back broach and
106:38 the formed continents. Now, if collision is ongoing and this plate continues
106:46 move northwards, which words to write this sketch with respect to Asia over
106:53 , it means that this fall first will continue to grow in that
106:59 So that means that this flexible we'll continue to move towards the left
107:08 this sketch or towards the south on . This will be the next time
107:14 . This will be a time step that. Does that make sense?
107:19 this deformation if we have a load and then we have a flexible for
107:26 from here. A broach here, both here and like that. This
107:31 here is sometimes called um the Flexeril . Yeah, so it's like the
107:43 the boots, the back boats, flexible waves. So if India continues
107:48 collide with asia and this 4th 1st continues to grow, this flex dual
107:54 will continue to move southwards in this . Right, So let's see what
108:03 means in practice. So what I've here is towards the left here,
108:09 load. So this could be the , could be whatever the rocky mountains
108:15 north America. What you see here that foreland basin very schematically shown right
108:23 deep. Here's the brooch and here that area or maybe even here would
108:31 the back boat. You can't really it here. Now again, this
108:38 basin here can be kilometers deep. brooch is maybe 100 m high or
108:44 . And then the back brooch is smaller than that. Now, what's
108:50 on this sketch is three points in foreland basin system. One here,
108:55 at the edge of the sedimentary one here basically on the back side
109:00 this bush and one here in, know somewhere where the continent is not
109:06 deformed. Now when this load continues grow and continues to grow in this
109:14 . So the 4th 1st belt of year continues to grow in that
109:19 Let's take a look at what happens points A. B. And
109:23 Over time. A. Here be . See there here there. So
109:28 gonna sketch that next for salt to time. And then we have three
109:38 to start with Point A. We out at sea level. So states
109:44 the on the formed continent. So A starts out here at sea
109:50 Now with time. This 4th 1st continues to low to grow and this
109:56 dual wave continues to move towards the . So what is the deformation uplift
110:01 subsidence is gonna look like in points over time. I'm not sure
110:26 And would you like to give it try? Yeah, I'm just thinking
110:32 was I'm not so sure right to A if this flexible ways move towards
110:44 right because the load continues to Point A will first become part of
110:49 for butch and then it will become of the deep basin, which you
110:57 The whole system moves towards the right .8. Okay, Right, so
111:07 a here will first become part of four broach and then it will become
111:14 of 40 basin. Let's take a at point B. So when this
111:21 flexible wavelength move towards the right, load move towards the right, what's
111:25 to happen at point B. Be like point she is. Yeah.
111:36 Point B would first become part of highest point of the boot,
111:40 It's now already at the beginning of book, it would become part of
111:43 highest part of the boot and then basin would move over it, so
111:48 it would become part of the So Point B. Is now located
111:51 little bit higher, it's already on beginning of the boot. So the
111:57 gonna move here be, this is be be, it's already a little
112:02 on the boot, so it's gonna at the top of the brooch and
112:08 it's gonna become part of the Does that make sense? Alright,
112:13 take a look at point C. would happen with point? See if
112:17 whole system moves towards the right. it would eventually be in the basin
112:32 ? Quincy is now located at sea . So let's put it there,
112:40 C. And if when you look , it becomes immediately part of the
112:47 . There we are. And then towards the left here, is
112:51 you know, the wedge top? it would become part of the wedge
112:55 ? We don't know, clear or . Um It's a little muddy for
113:05 . Yeah, it's a little bit . Alright, so where should we
113:11 it up here or earlier here, fine I guess, do you hate
113:21 ? Yeah, that'll work. so we're looking this foreland basin here
113:29 this one here doesn't matter. Looking one of these foreland basins. So
113:34 as compression continues collision continues this first belt continues to grow and as
113:42 false respect continues to grow, this continues to move underneath asia.
113:50 Right. So, point a here whatever, the number of the whatever
113:57 name of the point is, the here may at this moment be outside
114:02 the basin When this plate continues to towards the rights and this 4th first
114:08 continues to grow. .8 will first part of the four Belch, the
114:15 villages located somewhere there and then it become part of that deep sedimentary
114:24 Okay, I think maybe I was complicating it. Yeah, it's actually
114:31 story is very simple. So it just go into the basin area.
114:39 , not literally. Um it's you know, if we look at
114:45 a from a distance, it's not this material is eroding and an answer
114:51 the basin. It's like if we at this, this location on the
114:55 , what's gonna happen with that location the map. Right. So,
115:03 let's see if I could sketch it a different way. Here's the
115:10 the load is the mountain range and the flexible wavelength, the deformation associated
115:16 it when the load moves towards the with respect to this plate here.
115:23 next time step the load is going be here and this Flexeril deformation is
115:30 be there like this, That makes . Right. If the load moves
115:37 towards the right to here, then flexion of the information is going to
115:41 like that group. That was Yeah. So now at time
115:50 a point that is here on top the broach at time zero at some
115:55 time, that points will be located inside the basin and then some later
116:03 that point will be located in the basin. You see that same for
116:08 point here. The point now, point here is completely outside of the
116:13 . It's even not on the factual yet, but sometime later it will
116:19 gone upward on the flexible brooch. later it will be on the top
116:24 the flexion approach and sometime later it have entered the basin. Okay,
116:30 , I get it. Yeah, ahead. I'm sorry to interrupt.
116:42 I'm guessing the this is, I'm the reason to do this is that
116:48 deposition of sequences. You can just at those packages and see how they
116:53 the however the grade of the rocks the maybe un conformity and stuff.
117:00 can actually match those to these Yeah, exactly. The system is
117:06 simple because this here, where is broach topographic high in the landscape.
117:14 gonna happen? We're gonna erode it , It's gonna be eroded. So
117:19 book area here will show up in strata graphic column as an un
117:26 a missing a missing layer of it's not there because it's high
117:32 So you will see it back if drill a well stay here in the
117:37 basin, you drill a well and you can see if your well is
117:42 enough. You see basically this back it once um was part of this
117:50 . Do you know what I So you see in in the static
117:55 of the foreland basin, you see back? That's why we're doing
118:04 I'm gonna pass this for a So just to let it rest because
118:08 if we pick it up a second , it becomes more clear. So
118:12 there examples of like whatever strap columns show these patterns in them, then
118:19 of the stress columns of foreland basins these patterns? I guess that means
118:29 and its characteristic right? It's how one way you recognize that you're in
118:33 foreland basin. But let's let it for a few minutes and let's do
118:40 else in the meantime. So what gonna do, I'm gonna sketch for
118:46 . No, I'm not going to them and ask you to sketch a
118:51 basin subsided scourge of time, horizontal depths, vertical access past year presence
119:03 . So remember this morning, we at a subsidence curve for a cra
119:10 basin and it was slow remember It looked something like this. Now
119:19 we're gonna think about a subsidence curve a foreland basin to pick pick a
119:27 in a foreland basin and think about , you know, pick the deepest
119:34 layer in foreland basin. Think about that subsidence may have happened over
119:44 Slow fast, first fast and slow slow and fast. Any thoughts,
120:12 if there are no thoughts, I'm sketch it and then you can look
120:16 it and see if you can explain . All right, this is what
120:19 looks like. 1st. Slow then . Any bells ringing? Not
120:50 Look at the similarity between this curve And these three here. Mhm.
120:59 similar. Right, okay, let's back to a foreland basin. Let
121:04 think about if I can show I'm just gonna see if there's one
121:09 on that is clear. It doesn't like it's um Maybe I should go
121:29 . Um Let's go back. Oh let's let's go with this one
121:48 So think about how this basin was formed. We started off with a
121:54 crystal, right? And then and at one point in time a full
122:00 belt started to form. So maybe was like a thrust here. It
122:04 tiny. So that point in time meniscal basin starts to form here.
122:13 basin. There's not much loads, not many settlements. So subsidence minimum
122:22 spot starts to form larger, become , It builds up larger, A
122:27 note settlements. So what's gonna happen now this basin is rapidly going to
122:40 . No, so now we have deeper basin filled in with sediments.
122:48 full first belt builds up even We're now at the size of the
122:52 Mountains or the alps or the Himalayas we have a very serious rhone and
123:01 fairly high topography. High mountains produced sediments. So not only have we
123:08 the roads, we also have increased amount of sediments available to fill up
123:13 basin. So at this point in your vacation will be big and deep
123:20 filled up with sediments. So a related was deposited at the first formed
123:28 . It may now be here deep this sedimentary basin. So when it
123:34 formed, we said wasn't much there wasn't much, you know,
123:40 of the plate. Not many sediments wasn't very fast. But as this
123:46 started to build up, you grow weights, the loads on the plate
123:51 . You should produce more settlements. ? Much more settlements are being produced
123:56 a mountain range than from a little . So now you you you get
124:01 acceleration of the subsidence of the the foreland basin. So if you
124:07 at that over time, let me it here. So time, horizontal
124:15 depths or vertical access. You see subsidence slow when this falls were spelled
124:25 start to form not much weight. many sentiments subsidence is slow and in
124:31 course of time as the faults were builds up more eventually, subsidence
124:39 There's a huge loads. There's a of flexible information of the place.
124:44 there's a huge volume of sediments that up the basin and flexes. Everything
124:50 everything down even more. So that that what gives you that characteristic shape
124:56 a subsidence curve for a foreland But would that make sense or
125:06 Absolutely. All right, okay. I have a little bit of free
125:11 here. So let's check these two curves that we've looked at so far
125:18 let's put them on um one and one and the same curve. So
125:23 son to access this time passes towards left present days towards the right vertical
125:30 is depth or z. Now we looked at this photonic basins, their
125:35 lift. There's a tiny bit of . They do something like that.
125:39 compared to that. These foreland basins deep from fast. So they look
125:46 something like this that will be a basin. So, you see it's
125:52 huge difference. It's deeper. It's , much faster subsidence over a shorter
125:57 of time. This is how the compare. So you could see if
126:02 would give you such a subsidence You would be able to say this
126:07 a foreign land base and probably and is probably a a platonic basin.
126:13 see that the difference is really Yes, ma'am. Right. Let
126:21 see if we can go back to . Or let me see what comes
126:29 . I'll first talk about some other and then we can see if we
126:32 go back to the same place Um so it's now 3.30. So
126:39 have an hour and a half left thinking because we're running out of
126:45 which is okay. Um Now let's a couple of things I wanna
126:53 So if you're your plate sickness, elastic plate sickness is sin. You
127:03 form a foreign land basin that is and deep. So here's the lows
127:09 mountains of the loads. I'm gonna it. Your foreign invasion will be
127:18 , narrow and sin. So if is your foreign land basin, they're
127:23 in deep. Sorry, this is it is narrow. Deep foreland
127:33 Now, if you have exactly the load but your elastic plate sickness is
127:42 large. You have a thick elastic with exactly the same loads. You
127:47 form a foreign land basin that is but much shallower. In other
128:06 you could call this a wavelength Oops, you could call so the
128:15 of the factual deformation is much larger your plate sick elastic plate is
128:23 The manual realistic plate is thin. could call this a wavelengths. You
128:27 that from the brooch to the edge the load. You could call that
128:30 wavelength of the actual information towards the as well from the brooch to the
128:35 of the load will be a the wavelength of the factual information.
128:40 this makes sense. Sin elastic narrow deep foreland basin, thick,
128:46 plate, white and shallow foreland Yes. All right, great.
128:53 let's take a look here at foreland of the Himalayas. So this is
128:57 the lotus, right? The Himalayas right here. This is the Malayan
129:02 basin and the Himalayan foreland basin is just south. Exactly south of that
129:10 were spelled Now what you can see nicely in this map of India is
129:16 following here again in the north. is the load. Right the Himalayas
129:20 are loading on top of the indian . And here we have the indian
129:25 foreland basin around that area may be a little bit more towards the
129:31 but doesn't really matter Now. You also see very nicely on this map
129:37 the location of the four Belch and just gonna point it out to you
129:45 the reason you can see it is because you see high topography. Remember
129:50 though this Himalayan foreland basin maybe kilometers , the four votes was only maybe
129:56 m high or so. So you even see it on a topographic map
130:01 this. But you know how you find this because the river's flow towards
130:07 sides of this four Bush. So in the north we have the Ganges
130:12 coming down. And this can this , as you see, does not
130:16 south. You see that it finds way towards the right here, towards
130:20 east. Here, on the left , we have the Indus River.
130:25 Indus River is not going to go south. It's not doing that.
130:31 finding its way around this path and enters the ocean, the Arabian sea
130:37 there. So, in other those two river systems, they do
130:41 go over this area here and this here and this to some extent is
130:47 little bit higher elevation. And you see it because it looks different on
130:51 map. But what you see is these river systems can't cross it.
130:56 then you have other rivers here that off it and float towards the
131:00 So we have nothing that crosses this or this area. You see that
131:06 that is because this is the four . This is a region that is
131:11 a tiny bit elevated and it separates rivers towards the north from the rivers
131:18 the south. So it's it's even though you can't see really see
131:24 on a topographic map, but it affected in the course of millions of
131:29 , the flows of these river So that just gives you an idea
131:36 the size of this foreland basin Right, foreland basin is gigantic.
131:41 four brooch is almost halfway the indian . This is a huge system.
131:50 right, let's take a look at figure here. This figure here is
131:53 the Allen and Allen book. It's looking at the Himalayan foreland basin,
131:58 this is an ice a pac So what is an ice pack
132:02 What are we looking at? If looking at an ice APAC map,
132:11 ? Nope, almost looks like but it isn't a temperature.
132:20 layer thickness, sedimentary layer thickness. , take a look at this where
132:26 says six year, it means six , five will be five kilometers
132:32 So in other words, in the portion of the Himalayan foreland basin,
132:37 have 56 kilometers of sediments and then the south, you see the sediment
132:44 going down to about two kilometers maybe one kilometer here and zero somewhere
132:51 . You see that. So, is if you would draw a transect
132:55 this through this system, we call north, we call this south.
133:00 draw the transect north south in the . This is where we have the
133:06 there right here. Then you can here we have very thick sediment
133:14 So deep foreland basin and then we for the south and the thickness of
133:18 sediment package decreases. You see So let's sketch that in this is
133:25 it looks like. Deep basin in north and a shallower basin going
133:32 And then here somewhere here is that that is basically not visible. But
133:37 is there, Does that make sense no? Sounds like it doesn't make
133:50 sense. I feel like I followed . Good leo. Did you follow
134:02 ? I'm I'm good macon, are good? Yeah, I think I
134:10 got the powerful food. Can you ones to just make sure that what's
134:15 my head is right, here's the , here are the Himalayas, this
134:21 the mountain range, here's the south a vertical transect through this foreign land
134:30 . North south here at the you see in the north there's very
134:39 package of settlement, six kilometers up to six kilometers thick. Some
134:44 places even more towards the south, settlement package is much thinner, maybe
134:49 two kilometers or so, so that what I'm gonna sketch in this cross
134:53 . Here's the north, the Himalayas sediment package, maybe this is 56
135:00 or so. And then further the sediment package Peters out. You
135:05 that here, it's only two km so, and then here it's
135:11 That's all. Okay, so you that these foreign land bases are very
135:21 . You see that one side is deeper than on the other side.
135:25 always the case. There's always this . It's unbelievable asymmetric. Thank
135:34 Let's go to the next slide. talked about it before and we're gonna
135:40 it for now. And I'm gonna a little bit about the sediments that
135:45 in these um foreland basin systems. right. So, you've seen this
135:52 this figure before towards the left is 4th, 1st belt, and then
135:56 the right with the foreland basin The wedge top, the four did
136:00 four boats and the backbone first. look at the wedge top. So
136:05 gonna take a look at now where sediments come from and what this looks
136:09 in detail. So here on top this wedge, small basins may form
136:15 bases may be connected, they may separated or isolated. We call them
136:20 top basins or piggyback basins. the four deep is are the deepest
136:28 in a foreland basin system. This the deep basin. What we saw
136:32 the Himalayas, that could be like km deep or so. The four
136:37 can also be a basin. So only sketched it as a brooch that
136:42 sticking up above the continent, which see in India. But you can
136:47 that the whole system has much lower and that the four bolts could be
136:52 and settlements could be deposited there as and then we have the back toes
136:57 the back boat is tiny. You can't see it but may have some
137:03 . So there's some sediments that may up in your back push. All
137:09 , This is the simple 40 that sketched earlier. The fall first felt
137:13 , towards the left and the simple . The symmetry of the fault first
137:19 the symmetry of the foreign and And then here the boats. You
137:24 that right, That 40 is usually that simple. Um so, we're
137:32 it simple because it makes life easy , but in real life it's often
137:36 more complex. And you can see two examples of how it may look
137:40 more realistically towards the left is again 4th 1st belt. And the yellow
137:46 shows you the sediments that fill in basin. So the upper figure shows
137:51 a 40 basin. That is much complex. It has like trust um
137:57 somewhere in that base. You don't see it, but you see that
138:01 makes the structure much more complex Towards bottom here. A number. See
138:06 can see that the 40 basin is . It's almost partitions into two parts
138:12 out of parts and an inner And so that is also much more
138:17 than that I showed you before. , again, where do the sediments
138:22 from that end up in this 40 ? The tectonics from the left.
138:34 . Almost all coming from the mountains . These sediments, they will end
138:39 here again. Sometimes you may find sediments that come from the, you
138:44 , the other side of it, most will come from the, from
138:48 mountain range. Yeah, excellent. , let's take a look at these
138:53 stock basins. So the vegetable basins the ones that are here,
138:57 really on top of the toe of 4th 1st bounce here. They
139:02 Sometimes we call them piggyback basins. these piggyback basins there often completely isolated
139:09 each other. Easy that so they their own little, you know,
139:14 history and they may be separated from next one down the road sediments for
139:22 spiky back basins also crumb from the trist system itself. So they come
139:27 the mountain range and are transported in . Um But this figure shows is
139:36 you look at the foreland basin often not, you know, the
139:41 almost horizontal layers of sediments right that been sketching so far. But often
139:45 a lot of the information in that basin itself and that is what you
139:50 see here. So here you can sedimentary ladies that have been deformed
139:56 You can also see a lot of , but earlier on in time,
140:04 see, I want to show you foreland basin, the Persian gulf.
140:08 , the Persian gulf is also a land basin. Now, Persian gulf
140:13 because the sack rose mountains that are here um and are in those mountains
140:21 as a load on the plate So as a result of the loads
140:26 this mountain range here we formed the basin. The foreland basin is basically
140:31 here in this area. There we . Now, when you look at
140:40 foreland basin, you see that the and southern part are covered with a
140:45 of water. You see that this the Persian gulf, so it's a
140:49 environments. The northern part is completely up with sediments. We see this
140:56 in foreland basins so often when you a foreland basin, when it starts
141:01 form to form, we have, just sketch that you have a
141:06 you know, your your false response to form, there's a little bit
141:10 subsidence and the sediments that are available fill up your foreland basin. It's
141:16 very limited Now then your for your respects continues to grow. Now the
141:23 basin deepened significantly more sediments are available fill up your fourth, your
141:30 1st, sorry, going for your 1st belt and filling up your foreland
141:35 , but still, there may not enough sediments available to fill it up
141:40 later on then that's that 4th 1st is completely developed and there's now a
141:45 of erosion going on a lot of available at this point of time.
141:51 may start to completely fill up your and basin and that is what you
141:56 here in the northern portion of the . There are so many sediments available
142:00 is completely filled up the space in central and southern portion of the Persian
142:07 . There are not enough sediments available fill up the space and you still
142:11 a water layer as you see So this evolution is very typical for
142:18 basins. So we often start off something like this marine environment. So
142:24 have to be positioned maybe of shields other marine sedimentary rocks. Then over
142:32 as the fault first felt the focus and more sediments are becoming available,
142:38 start to fill this basin up. you may start out with a marine
142:46 . That is rather the the person is a rather deep ocean but a
142:52 . I have to say. And later on if you have more settlements
142:56 to fill up that that's basin, go to shallow marine sediments and then
143:07 when enough sediments are available to fill this this system completely, you may
143:12 to flu fuel systems for example. terrestrial environment, you see that so
143:19 um foreland basins, it's completely normal them to go from deep marine,
143:25 shallow marine to terrestrial of flu feel the normal um sequence of defense.
143:33 the deep marine shallow marine sediments, may be very organic rich, so
143:38 can form great um source rocks. then because of all this ongoing deformation
143:46 may take place in this foreland you can imagine that later on with
143:52 or fluffy oh, sediments you will excellent reservoir rocks and you will form
143:57 whole series of trips, you know these these sedimentary layers are deforming.
144:02 there will be many trips available in sedimentary basin. So that is why
144:07 lot of these foreland basins, the that we find for example towards the
144:12 of the rockies, the D. . Basin um foreland basins like that
144:17 the one here, the Persian gulf basin. A lot of these foreland
144:22 , they are um they have fantastic petroleum systems developed and they are used
144:28 exploration and production. So that explains we're interested in these foreland basins.
144:36 questions about this? No. All . I'm just gonna quickly go towards
144:44 end. Yeah. So what I like to do is so I've run
144:52 of time just let you to be with you um which is not a
144:58 . Um But what I would like do is see if we can go
145:02 one more time to this moving foreland system, migrating foreland basin system and
145:09 you know, the uplift and subside conformity is that go with that.
145:14 what I will suggest is that we a short break again 10 minutes or
145:19 then I'll try to explain that. after that the next thing on our
145:26 would be a um an exercise that a foreland basin exercise. And all
145:33 things that we've talked about today. flexion rigidity, effective elastic thickness.
145:40 And a figure as you see come back in that exercise. And
145:44 think we probably don't have time for anymore today. And so what we
145:49 do is just, you know, take it home, you look at
145:51 this week and then we discuss it weekend um on Friday. Yeah.
145:57 let's have a short um 5 to minutes break or so and then we'll
146:04 for the last hour of this Yes, ma'am. Already see you
146:10 a few minutes. Let's wait for and deal Oh right there.
146:36 Let's give it another try. And so what I'm gonna start with is
146:46 the left. So you can so if I do this, you
146:51 , it's a false respect, This is false rust belt. It
146:55 , whoops. It doesn't look Um there we are 4th first
147:04 but it's just it's the idea. then um towards the rights, we
147:15 the continent. So here's a And what we're going to assume is
147:25 here's north. This is this is and the continent is India in India
147:34 still moving northwards like that. So the moment we have um sexual information
147:46 . This is about what it looks . So we have here our Himalayan
147:50 that basin Now as India continues to with asia. This fourth wrist belt
147:58 continue to develop. So it will , it grew up and it grows
148:05 sideways. In the meantime, the continent slides underneath the Himalayas. So
148:14 continuous convergence. This moves in this . This fortress spelled growth growth.
148:20 is what's going on. So maybe five million years from now points that
148:26 here on the continent has now moved it's like here. Does that make
148:36 if this is the 4th response was little mark you made supposed to be
148:48 point in time? No point on continent. Okay, so name city
148:56 India which is in the center of continent. Let's find a reference
149:02 I would say it's in the middle the B E T H or
149:13 Okay, so this is where bobo today in five million years. They'll
149:20 here because the indian plate has moved the northward. So five million years
149:27 that Popo, hold on, I to remove my screen is the first
149:42 this year is the foreland basin will here. Great Go pro in five
149:51 years maybe. Well here five million . It may be on the broach
149:57 fractal electoral brooch And in 10 million it may start to have entered the
150:05 may become part of the Himalayan foreland foreman's basin Right? five million years
150:16 debt we will find it if this the first bell, these are the
150:24 . Here's a foreland basin, It be here this location. So this
150:40 not abnormal. So we're using the of India moving into Asia because it
150:46 fast. Right? So there's a going on. But as these false
150:49 student systems develop, you see a of times that there's growth monstrous forms
150:56 the other etcetera. So this is like an abnormal situation now. So
151:04 what does this mean call today? um let's sketch it. Let's sketch
151:13 , horizontal access and then elevation or vertical axis. So today how is
151:26 a few 100 m above sea level million years from now. It will
151:37 on the broach 10 million years from it will have gone off the brooch
151:44 starts to be in the basin 15 years from now it will be in
151:49 basin. You see that that's what meant. Okay if you would have
152:05 a different reference points we would have same curve but we would switch it
152:10 the left or right closer or further from them basically from the Himalayan foreign
152:15 mason got it great. So I'm make a different sketch now. So
152:31 axis is time. The beginning for past is down here and the future
152:41 the present day is down is up . So time marches towards the top
152:46 this fiction and now the worst. access is basically an X axis and
152:53 shows us the distance from the thrust to some extent. So in the
153:02 , the first rounds, the ends the first phones may have been here
153:07 over the course of time, the funds may have moved outwards with respect
153:14 that other place. Say the indian like this. So this is the
153:20 front. Does this make sense? . So it comes closer to Bhopal
153:33 the course of time. Now, from the first phone. So next
153:40 the first phones here, this is you would find your sedimentary basin,
153:45 ? Your foreland basin. If the also access is some kind of distance
153:55 away further outward from the foreland you find the four boots,
154:03 Right. So let's sketch in the butch And the four built has a
154:17 width. And so maybe the four looks like this. And then on
154:23 other side we have the back but it does not doing much.
154:26 let's not let's not focus on Let's just focus on this part
154:31 So, if the first fall towards left, the sedimentary basin in the
154:36 and the four built towards the does this make sense so far?
154:44 . So now we're gonna march in forward. So, we're gonna start
154:50 at the beginning point when the full belt first started forming you start forming
154:56 thrust belt. Maybe there is first first it's not very thick, it's
155:00 a lot of extra loads on the , it's not very high. So
155:06 gonna form like a small depression and small depression, it's just there.
155:13 it's probably not even filtering with sediments there's not many sediments available. Then
155:20 time, your fault first belt starts grow is for more, more
155:25 they stick on top of each they grow outside works, you build
155:28 much bigger system at that point in , your sedimentary basin becomes a lot
155:36 . But hey, you're foreland basin a lot deeper because you have a
155:39 of loads. But you know, whole system of rivers that transport sediments
155:45 the mountains to the basin, it's really developed yet. There's not that
155:50 sediments available yet. So that's the . Then we move forward in time
155:56 now we see a really about developed thirst belts. There are, there's
156:03 lot of erosion, steep mountain a lot of sediments that are transported
156:08 the basin. So what does this like? Eventually, when we start
156:13 , we have a basin, it's very deep, but those are not
156:17 up with sediments. So probably a environment like the southeastern portion of the
156:28 , the Persian gulf, this thirst builds up that the basin deepens and
156:35 enter maybe even a deep marine Then at bottom point in time,
156:43 sediments are going to become available to up the basin. So they fill
156:48 the space and now we only have syn water layer layer left. So
156:53 call it shallow marine going forward, have enough settlements available to fill up
157:01 whole base and like in the northern gulf. So we enter maybe a
157:07 flu feel system in film of the . Does this make sense? Towards
157:16 right here, we still have the boat. But as this first front
157:21 off towards the right, so does four bolts. Right, Because this
157:25 flexible wave moves towards the right, let's draw two cross sections through this
157:36 . We're gonna start with one at point in time and then we're gonna
157:44 one in this point in time. the first one A is gonna be
157:49 we have a deep marine environment and is gonna be when we have the
157:55 and completely filled up. And maybe looking at fluffy ecosystems, fluffy
158:00 So let's first do a. So . We have a reasonably well developed
158:06 thrust system, Maybe something like We have a, you know,
158:12 deflection. We have a basin but this basin is not completely filled
158:18 with sediments. Maybe we only have here at a deeper part and then
158:23 have a fairly thick water layer, a kilometer or half a kilometer of
158:28 on top. So we have a deep marine setting. And then towards
158:32 right here we have a four So maybe this here is the four
158:40 , let's transact a then 26 B B. We have a really loud
158:45 . 4th 1st front, it has up and sideways, we now have
158:54 deep sedimentary basin really well the deep re basin, we have a four
159:00 and this deep sedimentary basin now is filled up with sediments at large
159:08 You still find those marine and marine and shallow marine sediments. So
159:14 , deep marine shallow marine sediments but most recent layer of sediments is flu
159:20 it's here flu feel. And then we still have that four broach and
159:28 four broach now has moved towards the because the whole system basically moved towards
159:33 right. Does this make sense? , so this here we call a
159:41 o strata graphic chart. This is grown up photographic chart which is very
159:55 of a foreland basin Now in it may be a couple of um details
160:05 that we haven't talked about yet. what you often see is when these
160:09 first belts form, that's um they through phases in which they may be
160:17 up higher topography than building out. so the shape of the four of
160:23 fortress spelled forms of reforms, it over time. They may be higher
160:28 maybe broader etcetera. So that means the load on that plate changes.
160:34 then the load on the plate What we see is that the shape
160:38 the foreland basin changes somewhat. you can imagine that if you build
160:44 a thrust front higher up, but don't power it up outwards as
160:50 Maybe with your foreign invasion is gonna , it's gonna tilt backwards a little
160:55 . Or you can also imagine that first front builds up more roots out
161:00 , not so much up but out your foreland basin starts to build the
161:05 direction a little bit. As a of that part of that foreland basin
161:11 be exposed, may be uplifted and would form an un conformity. So
161:16 this, you could maybe imagine that , you could form an un
161:21 You have a period of non deposition even erosion or later in you may
161:28 a nonconformity here. You see So there can be changes in that
161:35 basin system that you know details on it forms that may cause. Some
161:41 the foreland basins were uplifted, eroded reform and nonconformity. So, in
161:46 a grown up photographic charge, you also put in an un conformity and
161:53 is really a period of non Writer of erosion. So, you
161:59 see it basically as a blocked out you know a blocked out part of
162:05 strata. Graphic column. This basically a strata graphic column. Do you
162:10 it now. Okay, so this sense. Right. All right,
162:21 think we are now ready. I'm summarize this information. What we've learned
162:29 the foreland basis. Let's go over and summarize it and that. Then
162:34 I'm gonna do with the exercise um have it already. So we sent
162:39 last night, it's called I think called foreland basin exercise. So I'm
162:45 gonna give it to you to think and see if you can do it
162:49 the coming week and then friday the first thing we do, we
162:53 start going through that exercise together. , so I'm not gonna take up
162:59 time to exactly five, but I'm give you half an hour back of
163:02 time that you can spend on that . So sorry about taking taking up
163:09 than I planned to do. let's go over these foreland basins.
163:21 these are flexible basins, writes and about that. These are flexible
163:28 So these foreland basins, they form to the mountain range, right next
163:33 the fourth rust belt. So the often elongated like you see, for
163:38 with the Himalayas. And um let's about the width and the depth of
163:45 foreland basins. Now, we started whole story by looking at plates,
163:52 plates that can be sick or thin we had a thicker elastic plate.
163:59 just to give away for the The indian plate thickness is very
164:05 It's a thick elastic plate. So start out with these elastic plates and
164:10 loading them with a mountain range. a result of that, these elastic
164:19 will start to flex. They started deflect and deform so they do this
164:29 in this particular case the sinner elastic . This is the mountain range that
164:34 this. So what does this Well, maybe I should draw a
164:38 bit more precisely. This if your plate is stick, you form a
164:47 basin that is rather white but not deep. Hm If your elastic plate
164:57 sin you form a foreland basin that narrow and that is much deeper.
165:13 just wanted to ask you in the short before it was thick elastic
165:20 It's just found by the old technomic it's narrow. And the right.
165:27 sick elastic plate. You find that we have all these little sphere,
165:33 example, Creatine is the course of continent's old little sphere. Creighton's.
165:38 cold court with a sphere. So the indian, the central part of
165:45 indian continent is old and cold. that's a perfect example. And is
165:50 narrow and deep? Yeah, narrow deep. Or white and shallow.
165:59 the thick elastic plate will be narrow deep. Right? No thick elastic
166:04 will be white forms of light and basin and the thin elastic plate is
166:10 easier to deform. So you form narrow basin that is much deeper.
166:17 the thick elastic plate has a rigidity . That is very large. The
166:23 elastic plate has a rigidity D. is very small. The rigidity,
166:29 Flexeril rigidity was the resistance to If you have a lot of resistance
166:34 deformation, it's difficult to bend the right? So you get a little
166:39 of bending over a wide area. the Flexeril rigidity of your plate is
166:45 , there's much less resistance to the . So you put a load on
166:49 and your plates just two forms like . It goes, you know,
166:53 becomes deep narrow, you have a of information, it's easy to be
166:58 . Does that make sense? so that tells you a little bit
167:04 the dimensions of foreland basin. Some are white and shallow. Other ones
167:10 narrow and deep. It really depends where you are now, what's white
167:18 basin? That is 600 kilometers or kilometers wide. That's really white.
167:23 Himalayan foreland basin is something like That's a white for a foreland basin
167:29 also be 100 kilometers wide, that's narrower. Deal, what do you
167:33 to say? I was just gonna , I think the west western Canada
167:39 basin is about, It's got to 500 600 km wide and the southern
167:46 . It narrows to the north. just to give you an idea of
167:52 a normal size is. Right, these are big basins, what does
167:56 mean shallow, maybe a few kilometers . Deep foreland basins can be eight
168:07 or so. So yeah, so can be these these are serious
168:13 right? Large sized basins really important the petroleum industry. Now, if
168:20 would have to guess the temperature of basins, the heat going, the
168:27 flow going into these sedimentary basins, would you guess? Normal temperature fairly
168:34 hot? The Oh yeah, the would be cold and she one would
168:51 hard. I wouldn't call it There's no magnetism or so.
168:56 But you're right, this would absolutely called low heat flow into the
169:04 That's what I would say this probably normal temperatures. I wouldn't call
169:12 hot. Right Holt. I would something where there was magnetism of
169:16 So I wouldn't call it hot, probably warmer. Yeah, you're absolutely
169:25 . And that that is kind of back to the elasticity that we were
169:29 about um with each model. now the sediments typical foreign and basin
169:42 these sequences that follow patterns. Deep marine, shallow marine flu
169:48 They go through those faces. They go through that several times during their
169:54 . You know, if something changes the load, right? You may
169:57 the basin or something like that. may deepen temporarily. And then you
170:01 go through that sequence again. So are called mecca sequences. They have
170:06 sequences of sedimentary study graphic um patterns . So again, normal would be
170:14 filled marine, shallow marine and they to fill up and then maybe even
170:20 or terrestrial when they're completely filled So they go through these, you
170:25 , patterns that make perfect sense. also saw that a lot of these
170:30 basins, there's internal information. It's these flats lying sediment packages,
170:36 And I'm sketching so as there is continent, continent collision or compression in
170:43 area, you can imagine that these packages maidenform as well. So it's
170:48 more complex than we're sketching here. you can also imagine that as a
170:52 of that, you may form many traps in these foreland basin systems.
171:00 . And then again, where do sediments come from? Some are
171:04 deep marine, some are shallow marine when this basin is filling up
171:10 um they're coming from this, this mountain ranges right to fall through
171:15 name. So with all these um these basins think about these components,
171:22 do settlements come from? How deep the base and etcetera? Another thing
171:29 we looked at is the subsidence history these basins. So because they start
171:36 falling, forming slowly at the there's just, you know, there's
171:41 small amount of subsidence and that accelerates time as this fortress style belt builds
171:47 , the load increases and more settlements available. Typical subsidence curve of a
171:54 basin starts out slow and then increases time. Questions so far. So
172:09 back to the examples that you just out in summary of everything. Um
172:14 example that was on the right um that generally considered better for petroleum systems
172:21 of the warmer temperatures? No I say it doesn't really matter. Um
172:27 even these white and shallow basins, often reach depths over the course of
172:32 of millions of years. Um That be large enough enough depth. So
172:37 don't think um I don't think it . One would be excluded. Do
172:45 know what I mean? Or less ? Yeah that's a really good
172:55 Any other questions or thoughts? No , not for me. Good Megan
173:08 . I'm good. I discard that with the once you just told so
173:14 elastic plate would be wide and shallow gold. Right? Yeah. So
173:19 is the opposite and why not? . Okay so this is the right
173:26 and it's very intuitive right material that's stiffer doesn't want to deform that
173:32 So they make sense that these Um Thank you. Alright. Deal
173:43 remaining questions at this point in Um No I'm fine. Everything's everything's
173:55 . So I'm gonna quickly find the um That I gave you and that
174:02 had hoped that we could finish in . I'm gonna find it and then
174:07 walk you through it and that that's we will end them today. And
174:11 I hope that this week you have to look at it. So let
174:16 open it. So it's a pds it's called for the basin exercise and
174:29 gonna try to share it with you screen here. It is. So
174:35 looks very very bad on the shared . Um looks familiar. Okay,
174:46 see. So you see here the equation that we saw today,
174:50 We talked about it. So w the deflection B was deflection rigidity.
174:56 have row and minus refilled at restoring . Q. X. Is the
175:00 . So this equation should look And then the little graph there shows
175:09 Persian growth now but we didn't talk it yet. And that's because it's
175:14 of this um this little exercise is solution to this equation. So the
175:21 is shown here. Oops, I can't sketch on it. Oops.
175:27 solution is shown below and it starts W as a function of X over
175:34 . And if you look at that , there's a W max and that
175:38 an exponent that has a co sign it has a sign. Now,
175:43 does that mean that exponents is associated the amplitudes of the deflection. And
175:51 means that the following when you're close the falls for spells and you have
175:56 deep for deep your sedimentary basin. saw that that sedimentary basin can be
176:01 six km deep or so. Then amplitude of the formation exponentially the
176:08 So that means that the four broach is the next blurb right. The
176:13 wave that it produces has an amplitude is a maximum of 100 m or
176:20 . So to order more than an of magnitude smaller than that of the
176:24 sedimentary basin and the back brooch, talked about that back brooch, that
176:30 reflection behind the four brooch, the coach has a maximum amplitude of only
176:38 so kilometers of the 40 basin, foreland basin, 100 m or 50
176:46 of the four brooch. And then in the back roads. So you
176:52 that that amplitudes of the information of wave decreases rapidly. And that is
176:58 exponent that you see in the beginning that equation now further you see any
177:04 co sign and sign. That's you , that flexible wave that goes like
177:09 , this this that's basically when you a cosine and a sine. So
177:14 basically makes up that shape. So the amplitude again, is the
177:19 exponentially decrease, very rapid decrease in and the co sign and sign together
177:25 you that wave. So that is that is stood. Now it is
177:30 function not only of X, the axis, but X over alpha and
177:36 is what we call the flex dual number. And I've given you the
177:42 here and then um it's related to flex dual wavelength. So we talked
177:48 the risk of a foreign land for example. So this flexible,
177:52 information has what we call a flex wavelength and flexible wavelength is two pi
177:59 . It's shown here in this um . So you're flexible wavelength is longer
178:07 alpha is larger. And then if look one line up at what alpha
178:13 , alpha is dependent on the right? D. So the more
178:19 your um your plate is, the , the realistic plate is, the
178:25 the wavelength of these formation and the effectual wavelengths. That's basically what you
178:31 get out of this. Now, can skip this. So here,
178:37 first question is, how does a wavelength relate to the elastic thickness of
178:41 ford in place? Well, when think about it, the thicker the
178:46 thickness is of this plate, the that wavelength is right, that's what
178:51 looked at today makes perfect sense. , if you plot, if you
178:56 in one in creation here into the , that's what you get out of
179:00 . That's basically what I'm asking here . It says sketch the deflection as
179:05 function of X. We've done that million times today, where the load
179:11 , you have the deep basin, you have the brooch, then you
179:14 the back broach, that's basically the the deflection as a function of
179:20 Yeah. So that is what you sketch at number two here at number
179:26 . Show what the relation is between zero. So that is the depth
179:30 the foreland basin, the maximum depth next to the four in the front
179:35 the 4th, 1st belt and the rigidity of the place. We can
179:43 about it if you have a very plate, a large effective thickness at
179:49 point in time, you're basin won't very deep. We said those basins
179:52 be shallow with white. You can it by plugging in one of these
179:58 into the other and then you see as well, right? Um Here's
180:06 more calculations and then the last thing do here and exercise is um let
180:16 see if there's one more thing, one more thing, there's two more
180:23 that you need to do. Um sketched for several points in the base
180:29 what will happen over time, If the system would be for
180:34 so points A. B or C later on the location of Bhopal.
180:40 this indian place would continue to move Asia, that is what you would
180:45 here, he would sketch, you , Bhopal would first become part of
180:50 broach, then it would become part the foreland basin. That's what you
180:54 be to do here. And then last um the last thing that I'm
181:01 here is something that we sketched just an hour ago photograph access years time
181:10 to access its distance. I've sketched what I'm calling the wedge, but
181:15 is the fourth response and then what would do in this figure, you
181:19 sketch in the location of the foreland , the location of the flexible
181:26 right. This broach that, that on the other side of the basin
181:31 then you would put in here where think at that point in time the
181:36 would be deep, so deep ring marine flew fuel, so basically very
181:43 to, to the exercise that we did in together here. So that's
181:50 . So I have to tell you is not a simple exercise and um
181:58 worry about the details. Um, is um, it basically covers everything
182:04 talked about so far in this weekend if you, you know, if
182:07 doesn't work out for you, you finish it, don't worry about so
182:11 it together in class next weekend and also give you the, the answer
182:17 . Maybe I already give you the key before next friday, so you
182:21 a chance to look at it before . Okay, so it's not
182:25 It's not like just putting something in equation and calculating something, there's like
182:31 thinking steps. Um, but it everything we've been talking about this weekend
182:37 then after this, we're done with land basis. They won't come back
182:41 on in the course. Okay this everything so that will be the foreland
182:47 exercise. Just give yourself like a an hour an hour to look at
182:51 and see if you can make sense any of these questions and then we'll
182:56 the rest in class next weekend. great. Right? So what I'm
183:03 try to do is stop sharing We are gonna meet next week.
183:09 you know what room? Yeah we're meet in SnR one. So the
183:15 so the building that's the department is in second floor in the computer room
183:26 . Yeah I think so yeah and there's one little problem at least that
183:34 have. I don't know if you a deal and if you have a
183:37 Hayden so I don't have the code that room. So out of the
183:45 I think it's will be open in but we need access to getting on
183:53 correct? We need access on saturday well. I used to have the
183:57 because I have done my three Making that lab. I can check
184:03 on friday if it's working. Yeah definitely friday but we just need to
184:08 be aware that before saturday we need have it because saturday will be in
184:12 room in the computer room the whole date and the building is open right
184:27 the weekends. Remember? But the open. Oh Fleming like Fleming with
184:40 lobby open before it. But the building will be open. Okay
184:46 And R. Will be open. but I have a slider key thing
184:49 get an S. R. Anyway . Okay. All right. But
184:53 make sure on friday if we figure how to get in the building and
184:56 to get in the room details. we gonna have coffee and stuff?
185:08 we gonna have coffee. Oh shape can we have a coffee in the
185:13 lab and building? Is that is side of the door will open during
185:19 weekend. So and I think the the computer level not close so so
185:30 can always have access to that. mean before they had coffee like that
185:36 don't let it inside but they have in the hallway. Right.
185:40 Can we have coffee in the You tie Do you think?
185:43 I'll try and have coffee for Yeah, especially saturday. Yeah.
185:54 we bring do we bring donuts and on Saturdays? Oh I hope
185:59 I mean I'll stop by and pick stuff up. Oh that would be
186:03 too. Yeah. We need to a place to have lunch on saturday
186:10 well. Right? But we'll we'll it out. Yeah. Yeah.
186:14 right. Find a place that serves you know? All right. We'll
186:23 that somebody for the first weekend. next weekend. Any question, anything
186:29 is unclear about this weekend, okay, you have a whole week
186:32 think about what didn't make sense, we can talk about it next
186:39 Great. Great. Well, I'm looking forward to meeting your own
186:45 Yes, ma'am, as
-
+