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GEOL6380 - Sequence Stratigraphy - Zoom_Bhatta-17
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00:00 Uh huh. So what we're gonna this afternoon is I'm going to give
00:09 lecture. Uh, this is a about not quite a field trip,
00:15 it's a lot of core information on . You know, this is not
00:21 much conceptual talk as sort of a example off a sequence strata graphic analysis
00:28 a unit that previously had only really a little strata Graphic interpretation on
00:37 If memory serves a lot, let's if I have that here.
00:45 yeah, yeah. Anyway, so is one of the few suspension bridges
00:50 the province of Alberta. And, , ladies, it's called the That's
01:00 Peace River. This is called the Bag and Crossing. And there in
01:05 little town of Dunvegan is right And this is the dunvegan formation in
01:10 cliffs on the road that you get to once you get over the bridge
01:16 it's a little bit of marine The base and mostly intimated flu channels
01:20 floodplains, these air pretty typical Alberta . Not the not the best across
01:25 world. So you know it's Is all the stuff from Utah,
01:29 that I've been highlighting the past few , so the dunvegan formation is deposited
01:36 in northwestern Alberta. It extends into C and a little bit of to
01:42 Northwest territories. Um, it drained part of an elongate, uh,
01:51 referred to by Crisco Taste, Larry and separated from appellation by the Cretaceous
01:57 during the early Senate. Man and steel was close to the south,
02:01 probably maybe just after done, it it was continuing. This movie,
02:09 sand was pretty low relief. That's old Transcom. A. It's been
02:16 long term drainage divide for much of history of North America, and so
02:23 source to sink relationships of the done a relatively constrained in terms of the
02:27 that's training and the amount of water sediment discharge available toe. Build this
02:33 into the Cretaceous Seaway. So this a regional cross section that goes from
02:38 , uh, from essentially British Columbia the Saskatchewan border, and,
02:46 you can see that it's an overall wedge. You notice that these these
02:51 mud stones above the done vague and relatively uniformed thickness the's great months
02:57 Stones will thinner here and then thicker either end. Dunvegan Wedge is really
03:02 it's quite a dramatic taper. Onda of a series of programming. Sand
03:08 banded by regional flooding surfaces reaches a aggression that about this point in the
03:14 on. Then there's an overall so it's an overall sort of
03:17 a little too retro gradation of plastic . The dump Meghan Proper refers to
03:23 units here with the letters. Eight that's overline by some younger formations.
03:29 the Times photography. So we've got Albion ceremony in Tehran. Ian stages
03:35 the Cretaceous period, and, and then we've got these fossils owns
03:41 show the relative fossil zones of the . And then we've got the
03:48 You know, by the time we to the Alberta B C border or
03:51 Montana Alberta border, all you have a series of shales, and all
03:56 sounds. Tones is long, so we finish, this lecture will take
04:04 break, and then we'll go on the next exercise, which would be
04:08 really diagram. And so this is the strata graphic correlation of the
04:14 and it's overline. Online formations across province of Alberta and that that's a
04:19 big chunk of real estate in that a good Oh, I don't
04:23 eight hour drive from northern Alberta to Alberto. You're not even at the
04:29 there is that. That's a pretty a pretty long distance. You
04:32 it's a scale. Here is that's kilometers. So that's about 1000 kilometer
04:38 cross section that's in pretty pretty good of real estate. Um, and
04:44 the widow diagram. So all of sudden you see that in the in
04:47 distant parts of the basin, So you've got a gray shale of green
04:50 on a gray shale on there's there's pretty big chunks of time missing that
04:54 contacts these air, not anger on . Is there not this conformity
04:59 These are basically big condensed sections, , uh, and there's, you
05:04 , 12 almost three million years missing , uh, the, uh,
05:10 underlying, uh, cast pal Sandstone the overline, uh so the underlying
05:17 sandstone and the overlying casket pal, in this area is called some kind
05:23 Vinny shells. There's all sorts of names here, Um, and they've
05:28 this nice presentational classic wedge. That's of the point of maximum aggression,
05:34 then it basically floods back and you overall retrogression. Retro gradation of stack
05:39 are also among conformity is in the of the wedge that likely correlate with
05:43 combination of sea level falls in sea rises. The wheel of diagram allows
05:48 to plot the photography of the Dunvegan its underlying overline Shales against the global
05:54 static curve developed by Pill Hawk and colleagues, both pre and post
06:01 And you know that there's a big level drop in the in the middle
06:03 the ceremony in at about 94 million . That seems to correlate with the
06:08 regression of the classic wedge. And this sort of super high stand at
06:13 91.5 million years correlates with this Cal shale, referred to as the second
06:19 white specks. The period of transgression to be associated with the condensed
06:24 so the maximum flooding surface appears to the sort of gross through it,
06:29 Hiestand from this overall second Sorry third low standard sea level again. You
06:35 see these other sea level changes and speaking when you when you got falls
06:39 cwc the wedges building out when you the rises, you get the big
06:43 sections. So, uh, going to the dunvegan formation. This is
06:53 cross section that that I put together I had determined that the sequence
06:59 So this actually has some of the flooding surfaces that identified the done
07:03 Um on that, of course, a 1994 from 1994 paper in the
07:09 of Western Counter Basin. Uh, proud of that. The best available
07:16 for the done. Megan was done Catania. Sing now to 10 years
07:20 a pack monologist that someone looks at that contain chlorophyll. And there are
07:26 groups of organisms that contain chlorophyll. is blue green algae and the
07:32 of course, of these little protests Donna flashlights. So, you
07:36 they move and swim like an But they have chlorophyll. Andre,
07:41 organic chief. So they're well preserved sediments and you can put extremely strong
07:48 in sentiments. Dissolve well, the and the Dina fragile. It's another
07:53 sports. We left over very resistant . What you can see is what
07:58 call a classic mythos photography. You , the dunk Bagan is sort of
08:03 to be all sandstone when in fact isn't. And it showed a sort
08:07 ah is extremely jagged edged formation that fingers with the with the adjacent formations
08:16 in in any one place. So one single vertical location, the red
08:22 the boundary between the underlying formation and overlying formation. So what northeast BC
08:28 cruiser Shale is over line by the closely Alberta B C border Shastri formation
08:34 overlaying by the Dunvegan formation and in middle of Alberta that Dunvegan formation is
08:41 is underlined by the Shastri formation. anyone place the dunvegan always over lies
08:47 underlying shale. But of course, know, here you have a shale
08:52 underlies it done vacant here. But tracked that shell in that direction over
08:56 . Right, So that's the inter problem. Let's see how good your
09:00 are. How did Wheeler solve that of into finger? What would he
09:04 done Thio deal with that finger of that the intrudes into the dunvegan to
09:11 left, and anyone remember what he have done to solve that problem?
09:16 line. Exactly. Excellent answer. . And what he would have done
09:21 simply drawn the verdict line. And was simply called, Uh, all
09:27 shells, part members of the Okay, Now, I'm gonna ask
09:35 a tricky question here. You notice there is a cruiser formation here,
09:40 shastri formation here on lavish formation. , so this share, if I
09:48 a line after a horizontal line so could get my pen working.
10:01 but if I draw a horizontal you know its share here, shale
10:05 share here. But the names Okay, So can anyone tell me
10:10 the names change? There's two possible . I think it's because if you
10:17 you have, like, a west or west east, as you
10:20 east across like wherever the plane, you lose the done vacant sands and
10:25 just get the more marine. So like a It's a function of where
10:30 call sign is right or where way draw vertical the boundary and say It's
10:34 share here. So we call the thing the beach. Here, you've
10:38 a sandy formation overline by share. we go from the beast of the
10:42 of power on. In that yeah, The boundary is a
10:46 arbitrary and arbitrary vertical boundary. what about between the shafts green and
10:51 ? Because that that's, you when the dunvegan is still there.
10:55 what? What What happens at this here? That we have a different
11:00 for this share their vs there. it bias? Your geography?
11:12 What critical boundary occurs? Uh, around here. Sequence boundary help
11:29 Yeah. You know what that It becomes a B. No.
11:37 what? Like to circle it? the province? Canada. Someone's got
11:43 geography. So if I draw vertical at the British British Columbia,
11:48 boundary, the formation names change. a That's a vertical boundary called a
11:53 boundary. Right? So the British geologist called the cruiser shell on the
11:58 geologist called Shastri Shell. Right. do you see the problem with little
12:04 ? You know, sometimes the difference there are because of political boundaries.
12:09 arbitrary vertical boundaries because the pinch out one thing. Political banners is even
12:15 anyway. So what we see What we see is that the base
12:24 the life of strata graphically defined Dunvegan is democracies. Okay, You
12:30 if I if I assume just horizontal , the base of the Dunvegan there
12:35 younger than the base of the There on a planet forms in
12:39 it's even worse. Okay, so clearly a problem. Of course.
12:45 anyone located in any one location, vertical succession always has the dunvegan overlying
12:52 underlying shape right in one D. obviously it changes. It changes because
12:57 the inter fingering. Okay. And course, the formation names change regionally
13:03 the same age and facing straight So the dunvegan is the same
13:07 Lopes. But because of vertical cut , uh, they're given different
13:11 right? And not saying there is logic to that for the for mapping
13:16 . But clearly it it's going to the genetic of the time strata graphic
13:25 . So my job is to try , see if I could do a
13:30 job of resolving the relationships between the Bacon, Shaftesbury and overline casket power
13:39 . And so I've already talked about when I talked about for methods about
13:45 fact that you know how I set my regional strata graphic grid.
13:51 someone had had marked a pinch out around about here, suggesting that the
13:57 programs from northwest to southeast. So ranged My cross sectional grid Thio represent
14:04 positional strike. Sorry. Deposition all versus de positional strike cross sections.
14:11 idea is, is if it was the clown it forms should differ in
14:15 direction. And indeed they do. , so one of the first things
14:21 did is the exercise that we did before lunch Where, uh and,
14:28 , you know, I had a of revelation in the middle of giving
14:31 guys the exercise E. I think time I do it, I'll give
14:35 a core or measured section first so can see the faces better pick the
14:40 there and then give you a well , which is has less information,
14:45 I e. I've sort of sort forgetting the fact that not all of
14:49 have have done petroleum geology And so of you haven't had any experience yet
14:55 with really looking at at at well at all was all of you should
15:00 had enough geology to be able to , you know, upper coursing sections
15:05 a core measure section. So, know, here's an example of the
15:09 Interval, this has got this is This is about 70 80 m of
15:13 . It's about 270 ft. Of . So there was You know,
15:16 of the interesting about about Canada is they do take a lot, of
15:20 , because where some socialist country, know, the companies aren't allowed to
15:25 that core forever. Canadians believe that land is is the is owned by
15:31 citizens ultimately required to give those course the government for permanent archive. And
15:37 it does well for science. What can see is thes thes shale toe
15:43 Paris sequences overland by flooding services. , back in my PhD, I
15:49 those minor flooding surfaces. Today we call them a flooding surface, and
15:53 could see that there is one to , 456789 Quite a lot of these
16:06 surfaces and and we can we can the flooding surfaces that we see in
16:09 core where we can interpret and observe environmental faces. And then we can
16:16 that to the well long on this simple. Here you can see the
16:21 right here. That's my little symbol roots. So that that indicates that
16:29 that in here we have, we some non marine sediments and evidence for
16:33 very exposure, and sometimes those surfaces severe exposure will will be sequenced
16:40 So if you drop sea level and the land surface, a river may
16:44 a valley or the or the area simply get exposed to the air and
16:49 a failure. Assault. We'll talk pay, solves more when we talk
16:54 flu viel sequence photography, and you recognize this log. It's got,
17:01 , highly radioactive shares. The base radioactive market at the at the
17:07 so these would be the two third convinced sections, and then you've got
17:11 of inter bended, uh, mostly and thin sand stones. And then
17:16 broadly sandy succession consists, consisting of series of Paris sequences safe. So
17:23 is very similar looking to the to well log that I gave you.
17:28 this is from a different part of formation, and so it's not quite
17:32 the same. But it generally uh, shallow Marine Deltek facing successions
17:40 with a non Marine middle area and back into marine shallow marine Deltek facing
17:48 . So the idea is, we're the faces and the key surfaces.
17:52 law surfaces in this case, flooding and severity exposure surfaces, calibrating those
17:58 the core. So these the key that I picked in the core is
18:02 I translated into the well loans. , then, is a regional cross
18:09 across my thesis area showing the dip photography. This has the wells on
18:15 , so you can kind of see well low correlations. Thes thick black
18:20 represent core, so that believe that's That's the core I just showed you
18:24 . There's there's quite a few of cores across this cross section,
18:29 and scale here is 2020 kilometers, this is about 200 kilometer long cross
18:35 . So again, fairly fairly decent of real estate. And it goes
18:39 from the from from reasonably proximal, sand dominated Dunvegan to the to the
18:46 part where all the sand is It's all Shales. And I didn't
18:51 any further into the basin and it be served. Uh, since yesterday
19:00 you show the different ways to interpret sections that one could go Maurin,
19:05 lift a lot. Look a lot connecting mythologies or using more of the
19:12 forms like you dio what would have a piece of data that we would
19:18 to make sure this is one cent or those air multiple sent bodies.
19:24 imagine if the Providence is the then we would we would get very
19:31 . Maybe core information I was saying pressure, uh, the key to
19:39 sure there No, no, no, no. It starts
19:42 It starts with the observations in one . Right. So let me try
19:47 make this clear, right? The work Assume the dunvegan we just all
19:51 big sandstone. Now they do show there is into fingering that they're implying
19:56 this is just sort of a A gradual faces boundary. But the
20:01 tell us that that can't be the . We have these nice upper coursing
20:05 accessions with these sharp waffles law uh, flooding surfaces that that that
20:12 indicated these upper coarsening cycles of deposition abruptly terminated by flooding surface.
20:19 So that suggests that correlating all this just simples ISMs is the wrong way
20:24 go. What we want to do pick those flooding surfaces is one in
20:28 d and then correlate them across the in the cross section. And we're
20:33 that. We realize that some of flooding surfaces correlate over the entire cross
20:40 , you know, and and those surfaces which I'm highlighting the red the
20:44 flooding surfaces separate thes off flapping uh, into these larger scale upward
20:51 , name off, flapping shingle Paris sets on. The key observation is
20:58 these flooding surfaces extend for over 154 kilometers. Okay. And that's and
21:04 the result of correlating closely spaced longs. And it all starts with
21:09 observation of upward coarsening with a surface violates Walther's law called the floods flooding
21:16 on the assumption on the model says the flooding surface, you should
21:21 That makes sense. Yeah. now, if we look at the
21:27 cross section so now the flow is towards. We can see you
21:34 some of these Paris sequences of dipping multiple directions. So we have a
21:37 of compensation here, and then they're then their wrote it into by these
21:42 valleys. Okay, the size of incised valleys dangled down from different
21:47 it's a little hard to see This incised valley system is dangling from
21:52 top of Unit D. This one is dangling from the top of unit
21:58 and thes. This valley system is from the top of unity.
22:03 on. And of course, these here will feed deltas in more distant
22:08 will see. So this kind of strike section allows us to see the
22:12 values Quite clearly, it's pretty clear these incised valleys are eroding into several
22:18 , of course in Paris sequences, we'll review incised valleys and flew deal
22:23 the next major lecture, which we it today. Or we may say
22:27 for next week on and Of course can. We can. We can
22:35 the secret strata graphic cross section and turn into a wheel diagram, and
22:40 could help us find a novelist. . And obviously, the critical thing
22:44 that allows you to compare the times with global cycle charts. Mhm.
22:53 let me go back to campus to question about you know how you know
22:57 , you know, you know, kind of getting to the part of
23:00 difference between a little and sequence So in the sequence photography, we
23:06 a Siris of procreating Paris sequences. , and then they're overland by big
23:13 surface. Right, So we have pro grading Paris sequence, a regressive
23:19 programming Paris sequence. A regressive of Paris sequence on this, of
23:25 defines a an aggregation of appropriation. press sequence set. Then there's a
23:30 flooding surges. Then we see another unit, another programming unit and then
23:38 regional flooding surface. So then we another aggregations appropriation of Harrison consent.
23:45 then that cycle repeats appropriation, scene of the fallen procreation, another
23:52 flooding. So once again, we in a p d. A combination
23:58 and then that that repeats in the units may get another big transgression.
24:03 these regional flooding surfaces that correlate over to hundreds of kilometers were used by
24:12 . So I used them as the for, uh a subdivision of the
24:21 into these off flapping Paris sequence Now, when I did the work
24:27 in 1980 80 so I was my was between 1984 to 1989. The
24:34 Paris. He didn't exist, but talked about shingled geometries in seismic
24:42 The word chloroform was around. It used very much. So I called
24:47 things shingles and, of course, moralizing para sequences on. Of
24:55 what this correlation does it places sand of the Dunvegan Formation unequivocally demonstrates that
25:02 age equivalent to Shales that will be in the shaft re formation. So
25:10 there's the chasse spree. There is done babe, right? So that's
25:16 lift. A strata graphic view. those clown forms go away. The
25:21 that Dunvegan consists of the Shales extend back in the formation is lost on
25:27 back to sort of chasms and maybe couple of tons, So yeah,
25:31 is. There is inter tongue no doubt. But the nature of
25:35 into tongue is really glossed over in little strata. Graphic view on its
25:41 insufficient to define the reservoir. on units that form the better key
25:46 define the pay intervals in the done information. What was the what?
25:56 was the target of interest? Main of interest. Which reservoir of that's
26:02 pretty complicated Question, uh, that produces in areas. A lot of
26:07 incised valleys produce this low stand delta . So almost none of these lower
26:15 to produce most production is in the in the is in the is in
26:19 most distant progressive phases phases and and some, uh, incised valleys and
26:26 retro retro traditional phase. Okay. the duck bacon is mixed oil and
26:31 reservoir. So most of it, , most of its in this upper
26:36 . Is it sourced from the Shaftesbury from, uh, E. I
26:44 the source rock is down here in fish scales. Wanna believe or
26:49 Even I did my PhD. I I don't know if I've ever read
26:52 you all having a pretty sure this a quotation petroleum system. Uh,
26:57 . Thank you. So, so you know, the little particularly
27:03 , you know, the overall classic is a map of a unit.
27:07 , uh, the little strictly sort implies some notion of little little.
27:13 , huh? Homogeneity. Um, and And the little stressed the little
27:21 , the little the little formation of . The little strata, graphic
27:25 or holly die, agrees. And secrets photography. The emphasis is still
27:29 on the correlation of bounding surfaces over of of kilometers. So clearly that's
27:36 allows us, allows me to map . So So the reason I'm doing
27:42 secret photography, which I used Alice back to my PhD was because thes
27:48 were critical to make maps of the bodies. But in my case,
27:53 units that I mapped included sand and . So I had a mixture of
27:58 in my surface bounded units. So correlating cycles that have variable ethology,
28:04 just gross mythology and, of the the members that I subdivided.
28:10 I divided the Dunvegan into Siris of . I call them Allah. Members
28:18 those Allah members comprised the sets of flapping Paris sequence sets. I didn't
28:22 that term off flapping Paris sequences in day. I just call them Allah
28:26 , but in secret strata graphic that's what they That's what I realized
28:30 were. And these at the Paris Down lap onto that convinced section the
28:35 scales upper marker, which is a radioactive, uh, shale on the
28:40 logs. Now, before I did work, you know, the only
28:49 tool for mapping the sand stones and was to map on the base of
28:52 little photography. So here's the Okay, so what we see
28:58 you know, a scene with tapering of sound. We see some very
29:03 lobes here, you know, And would be very tempting. Thio be
29:11 tempting to sort of say, there's Cem. You know, you
29:26 sort of assume some rivers and deltas their, um yeah, but part
29:33 the problem. You know, we a load here, but is that
29:36 you know, this tongue, or it that tongue we don't know?
29:40 maybe it's just a artifice of two added together is that we don't we
29:44 really know what. I don't know that's one flow unit of three flow
29:48 , whether it's an artifact of mapping really does represent a discreet, isolated
29:54 on. Of course, it's hard know how these tongues related to the
29:57 languid sand stones. So in when we when we pick an isolated
30:05 sandstone and pick one of its Paris and feeds, we get a much
30:10 coherent map so we can see There is the Valley breaks up into
30:15 channels okay and feeds again. Here a nice little big Delta that's probably
30:20 by at least three distributor channels to . We get a much more coherent
30:25 map, of course, that allows to to turn that into a paleo
30:30 . There is the paler geography of sandstone. I is Elif map,
30:37 . And of course, what that us to do is make Paley geographic
30:42 of all of the Paris sequences or each of the Paris sequences. So
30:47 , instead of having one big blob just undifferentiated sand, I will be
30:54 to make 20 maps of every single sequence, which has a flooding trail
31:00 top. So those of that represents basic reservoir compartments of the dunvegan
31:07 In addition, because I've broken broken into genetic units, you could start
31:11 see the complexities of the edges of sand stones, which are critical for
31:16 the nature of the type of the . Whereas when you look at the
31:22 map, you know it's it's hard know e. I mean, this
31:26 broadly interprets Deltek, but it isn't dominated. Is it tied, dominated
31:31 river dominated. And the way that interpret the type of the Delta in
31:36 to looking at the core faces, the actual shape of the of the
31:41 of the margin, the sand Okay, and we'll talk about that
31:46 just a little bit. So what shows is that Allah Member E,
31:51 is the most aggressively programming part of dunvegan, uh, looks like it's
31:57 low bait deltas and in plan They look, they look like they're
32:03 river dominated. Delta's okay, and then we'll be going to the back
32:09 part of the Dunvegan. We start get linear sand stones right that parallel
32:15 the shoreline on these Look much more on there. And when we start
32:20 look at the environmental little faces based the cores, they confirm those interpretations
32:27 the deposition environment. So the mapping the sand bodies is corroborated by the
32:33 of the little faces. One of things that I was struck when I
32:37 to the States is how little core commonly are in formations, particularly the
32:43 Coast. On I realized that I lucky in the gun vague and to
32:47 an enormous amount of core data to truth. The faces in the well
32:52 that really helped thes details correlations. the duck bacon consists of about 19
33:00 sequences on ground bounded by thes flooding on these flooding surfaces are fairly
33:10 Those air those of these flooding surfaces on, they're probably, you
33:15 little of ocean cycles. Okay then the Paris sequences are organized with
33:21 are flapping Paris sequence sets, which find is my our members. On
33:29 Allah member boundaries are mawr extensive flooding . So I got this idea of
33:34 this research. They were funding. were small distance. There were flooding
33:42 that crossed the whole area. And idea is those regional flooding surfaces were
33:47 allergenic in origin. Maybe there were significant transgressions going. All that drove
33:53 . And in addition, there was , particularly the strike view of several
33:58 valleys that indicated that there were some fledged drops of sea level. So
34:02 began to realize that within the Dunvegan wedge, which which is an overall
34:07 order, regression and transgression, there higher higher frequency full flight sequences within
34:14 . So I realized that I could the correlations that I did, which
34:18 which used Alice trata graphic terminology And I could interpret that using the
34:23 strata graphic terminology of Paris sequences, sequence sets, systems, tracks and
34:29 . Okay, now that I finished PhD and, uh, guy
34:36 who was a post talk, McMaster, who overlapped with me while
34:42 was doing my PhD? Uh, arrived a little bit just a little
34:48 before I did, and I arrived September. He arrived in May,
34:53 during his first summer, he went and did some work on the dunvegan
34:57 . I hadn't even started my my PhD yet. And then on then
35:02 showed up, and I have no why very quickly started working on the
35:08 formation and working on that for about , the universe. And then after
35:15 graduated, I decided to go back begin working on the Dunvegan again.
35:21 back in about 1990 guys who went to Dunvegan and of course, I
35:26 done the distal end of the So he decided to work on the
35:30 proximal areas that included outcrops, well, Azaz shallow subsurface data.
35:38 he and his post off Gen. Worth Matt Matt thes amazing inside value
35:46 on I was I wasn't 100% sure the units that I found you know
35:52 units? Sure. Yeah, I uh, whether they really just channels
36:04 incised valleys and and and gone. for Matt, Matt, attributes of
36:13 based largely on on well logs, without crops and said, Yeah,
36:18 were definitely in size values some significant level drops associated with the baby.
36:23 an example of some of the NSA's . That guy managed toe.
36:27 I know. Okay, So maybe little bit of trouble with her computer
36:35 on these rivers about about these lateral surfaces. Meandering stream is about a
36:42 m deep river. That's a big . Okay, again, implying sort
36:46 a valley scale system. And God also noticed that the valleys were multistory
36:51 places, so they're quite thick. talk about values for these big
36:57 All surfaces here with smaller scale channel inside them. So here you have
37:03 verdict in stack channels in erosion That's deeper than any of the individual
37:09 . And that is evidence that this a Valley scale feature and he was
37:15 to map that in unit E as as in some of the older
37:20 So there were evidence of big Seattle in some of the older units that
37:25 just worked on the distal edge. I never got to be to the
37:28 viable counterparts. Uh, what's interesting that is, that is that the
37:34 was able to map the end of the valleys alway upset to the sort
37:39 where the value is quite deep. once the Valley disappeared and turned into
37:44 channels, he was no no longer to map the terminal distributor chance.
37:51 the details of the rivers that actually the delta were lost. All you
37:57 match was the end of the and there was get about another 5200
38:01 from the end of the valley to actual shoreline. But of course,
38:05 the area where the rivers no longer , they're just single one channel depth
38:10 deposits building out over the delta, opposed to inciting into the delta.
38:20 , and so here is a map the four Paris sequences in Allah Member
38:27 . From that flooding surface that flooding on there is the the first Delta
38:32 Matt that it jumps that it shifts . I sort of draw a line
38:36 there. That's line there. Eso can see that there is a fairly
38:41 of that. The Delta sort Here it's been about a 50 club
38:45 . Jump in the position of doubt quote from step for Step three.
38:51 you look at step two, you that the this delta here lies sort
38:55 in the position between these two so there's some aggression, but this
38:59 a bit more just lateral compensation. then again, if I draw a
39:03 marking the limited shorelines and to that's line there again, we see about
39:08 50 kilometer jump in the position of shoreline, going from two Thio Unit
39:15 so that that's a pretty that z line there Thio there. So that's
39:23 pretty significant jump in the position of on, of course, evidence that
39:26 is an incision buying and size value through the feature that I mapped.
39:35 what we're gonna do now is take little virtual trip to look some
39:42 just get rock face is a Off town. There is the final nodes
40:06 the youngest and most distant most Paris . I have a syriza quote
40:27 We just in case we, Maria's not ever got the second half
40:30 the lecture. It's not critical. is more sort of a field trip
40:34 class lecture than essential information, but reinforce some things I've said before.
40:41 again there's the valley, okay, there it is in the court
40:45 Uh, there is the delta that again. You notice that this kind
40:50 a bypass zone here massive place where valley ends and we have distributor channels
40:56 some of those are maybe contained, know, within within the health of
41:01 profiles on some of them have been it off when this system got
41:12 So the secret Spanish pretty clear with valleys deep. Then it rides,
41:19 down and ultimately underlies this big, stand delta system. So there's the
41:25 the previous Delta, which is uh if you will the late
41:30 Then we get this incision and then get the low stand delta. When
41:34 get a clear sequence sequence, boundary with the incised valley, the
41:38 it's the high stand. And on we get this attacks low stand in
41:43 we have low stand delta kind of to ah Hiestand Delta with a sandal
41:48 contact and and and we'll look at some of these cores and a bit
41:52 detail. So this is pretty, , the same cross section, But
41:57 just I've just taken off all the Wells just toe just to get your
42:00 focused on the key. You know there's the high stand, There's the
42:05 . There's a sort of the area between the valley and the low
42:09 And here's some chorus that will look to illustrate the various faces associate with
42:14 Hiestand Delta, but no stand delta valley in this area in between.
42:20 here's the court section. So this the well logs Gana on left re
42:26 on the right. Uh, in case, it's been hung on a
42:30 datum. On that condensed section, black represents the cores. So here's
42:35 core cross section. So we see Hiestand Delta incision by the Valley.
42:41 take the base that valley and track seaward and that it underlies this low
42:45 delta. So let's have a look the high stand. So we begin
42:53 a little Paris sequence boundary there. we cease, um, stratified sand
42:58 with a low level of borrowing, little flooding surface, and then we
43:02 into a thick, hetero, prolific of relatively low bar debated mud stones
43:08 sand stones. We've got some Brown right lenses and classes here. That
43:14 indicates, uh, early formed a little modules, probably because of the
43:21 mixing of the of the river It's a nice little parallel laminated sand
43:26 and here into bed with mud that really key here is that the lack
43:31 fire tube ation and James, Macaque I and others have published on these
43:36 stones and identify them as as as pro Deltek. Based on the sentimental
43:43 and the trace fossils, we Courson s so you can start to see
43:49 the headlights are sandstone is getting increased their thickness. We see some nice
43:55 on pillow structures There. These were by sand building out over high porosity
44:02 and sinking into the clays as a a load cast. And then here
44:06 have the top of a little distance . Let me go from slightly.
44:10 faces back into money, pro Delta lifts and there's another little Baldwin pillow
44:15 there. So that Zatz one of Paris sequence boundaries, uh, so
44:23 believe that you that that's that's He comes three. Then we go
44:26 two. So this is so that , that's the Paris equals three and
44:32 boundary we go into Paris equals Uh, that unit shows a fairly
44:37 mud stone. Then we see a contact. We go into a parallel
44:43 sandstone, probably little term light And then that goes back into a
44:48 silty unit. And we see inter parallel laminated sound stones. Okay.
44:54 then we see these deformed sand stones ball and pillow structure. Okay,
44:59 ball on pillow and internally these ball pillow sand stones. You can see
45:04 here. But this sandstone here and ones are just completely filled with uni
45:10 current ripples. So this is extremely deposited. A little waning flow
45:17 little frontal displays, just a river that's just spewing settlement like crazy.
45:22 it's like black mud stone. event layer, which represents a river
45:28 deposit that form the front display on delta front, then went back to
45:32 delta. Another display proedl display and sedimentation was so rapid that a lot
45:37 those sand stones the claims were deposits rapidly they were unable to the
45:42 So when the next came out I sank into the waterlogged clay.
45:47 and sometimes the sentiment restructures have preserved the load cast don't form. So
45:53 soft sentiment deformation is really diagnostic of rapid sedimentation that suggests that we're in
46:00 shell memory environment directly see word of river that's just just pumping settlement like
46:08 into the into the into the inter waters. We begin thio course and
46:17 , if you can see this. there's some little ripple lamination here
46:21 lamination and these air climbing ripples those here. So the climbing ripples ripples
46:27 here as well. Those climbing ripples indicate extremely rapid rates of sediment delivery
46:33 the shallow marine area. We start see cross bedding, possibly indicative of
46:41 , uh, in our mouth bars possibly distribute terry channels. So we
46:47 get up into the Upper Delta front as we go into the top of
46:50 sand body. At this point we see evidence of roots.
46:55 you see these vertical traces here? those routes that indicates severity exposure of
47:02 Delta front indicating that sea levels Okay, that's Severin exposure surface is
47:09 adjacent to the big incised valley that of sea level trump drop. The
47:15 just didn't cut here. So we what's called an inter flu pale,
47:18 soul area next. So if you , there is there. Here is
47:25 inter flu where the trees growing on roots on adjacent to that river That's
47:32 cutting a hole. Okay, so course taken adjacent to an incised
47:38 Now, above that, we see little paralytic coastal plain floodplain unit with
47:45 lot of soda, right modules and material on. Then we see this
47:49 strange surface here that separates these swampy sentiments from marine bar debated
47:57 So this is marine bar activation. that is the transgressive surface of
48:02 That's when the waves came back across area on the area went from non
48:07 back Penta Marine. Then we have aggressive transgression. Let me go from
48:16 of marine muddy sand stones Teoh, sandy mud stone. This has bar
48:23 that goes from left, right, it's very horizontal bar intubation A man
48:28 fairly distant shellfire, activation of the fight. The signal faces Andi,
48:35 this is all very slowly deposited transgressive . Eso There's an initial surface of
48:43 wave transgression and then we get a a half a meter of transgressive sediments
48:49 there's a razor sharp contact there. now we're back into laminated pro Delta
48:54 stones. Okay, so that maximum surface there is probably a down lap
49:00 separating the retro gradation, transgressive sand . Sorry, transgressive mud stones and
49:06 stones from the probation mud stones of next pro grading parents consent. So
49:12 crop in the past breakfast now, next thing we see. So So
49:21 just looked at the fact that there's surfaces very close together. At the
49:25 of that Hiestand core, we see submarine exposure surface that's gonna correlate with
49:31 incised valley that was over line by swampy mud stone succession. Then we
49:37 the transgressive surface of erosion that ultimately the most. Stand on,
49:42 with a little transgressive faces in and then we get the end of
49:46 end of the transgression. Andre. flooding surface on top of that.
49:53 let's look now at the strike Okay, so here's the strike section
49:57 the valley. Begin their, example of the interpreters that we just
50:05 at. There's another one there. then we see the value cutting way
50:11 cores that penetrate the valley and lo behold, sharp based, fining
50:18 sharp based, sharp based finding You can also try spelling it like
50:23 is doing some things. Fuck. , of course, you know,
50:28 this is familiar from the well, saw you saw down profile at
50:31 basically fining upward. Okay, so the course section, right. And
50:37 the course show, um, Razor sharp erosion will contact that separates
50:43 coarser sand stones from pro delta mud . That's eroding out Delta. Take
50:49 equals on. That's not next in . A river channel should be adjacent
50:55 a Delta front. It should be of the delta front, right?
50:59 should be adjacent to a floodplain. the anomalous juxtaposition off Louisville phases anonymously
51:06 into marine phases indicates a criteria for . Pounder. In addition, if
51:12 track that faces to the left, see that there is the truncation we
51:17 this little little facing this little contact the right. We see truncation,
51:23 that go back to Geraldine's question. various criteria for identifying sequence boundary are
51:31 of adjacent layers, as well as anomalous super imposition of a shallow water
51:38 in armoring little faces. Environmental little over a deepwater faces doesn't have to
51:45 deep water, you know it could shallow Marine over less shallow Marine or
51:51 or or flu deal over shallow He doesn't have to be. Doesn't
51:56 to be flu Leo over submarine It just has to be a
52:04 which shift in face. He's that's on is defined by surface that violates
52:13 law. Okay, let's look at contact, you may recall. I
52:19 you this picture yesterday when we talked methodology, and now we have the
52:24 core photograph. But now you have strata graphic context. Here we see
52:28 nice laminated pro Delta mud stones of underlying high, some share of rip
52:34 class, all sorts of share report , nice cross beds representing the flu
52:39 channel processes. Eroding into a pro on that contact is is a razor
52:46 contact. The anomalous, anomalous Lee coarse grained flu video over more distant
52:53 pro Delta and that that that contact waffles law. There should be a
52:59 of it in between, and it's eroded out because there's been a drop
53:03 base level indicating formation of a sequence . Okay, let's just look at
53:09 particular core eso Here we have the stones. So here's bottom. There's
53:15 . We can see. Uh, little great in bed. They're indicating
53:19 pro tel two terabytes, a little storm beds again. Let's look great
53:23 bed. They're low levels of indicating high sedimentation rates. Onda stressful
53:31 , which indicates a marine environment that's aggressively being inundated with sentiment that that
53:38 Marine info are unable to survive And there is the contact that puts
53:44 flu viel channel overlying the pro Delta stone, producing a faces contact that
53:51 Walther's law. Because the flu viel not next in succession over pro Delta
53:56 be pro delta. Then Delta then distributor channel, then flew.
54:01 not incised Valley over pro Delta. the Delta Front and distributed channel faces
54:06 missing. This may be a little to see, but there's some.
54:09 is some angle of repose, cross . And then there's some rip up
54:14 class here in the overlying flu viel , we go to the top of
54:19 channel, we start to see parallel . We start to see beautiful,
54:25 , stacks of thes. We're all ripples here. Little ripples units,
54:31 little stacks of calm and rippled Some ripples. And here is,
54:35 , where else? You know, little rippled units, and here you
54:39 see on what we see is little little floodplain units. So overall we
54:44 we get little stacks of finding up units, a little short patient with
54:47 lack that finds upward. And so sort of represents the abandoned channel fill
54:53 Looks like it's still pretty flu deal the, uh that s so this
54:59 the basis of political channel, based the Fleagle Channel here that grades
55:06 into the upper channel Failure Valley Phil then the top. We have this
55:11 erosion surface. It's zipping erosion surface its separating these abandoned flu. Viel
55:21 fills from this marine, uh, of muddy sandstone sandy mud stone.
55:29 if we look at that in It's Xue Fei Kaspars in here and
55:33 Sufi Kaspars characteristic of middle shelf that a fairly distilled trace fossil assemblage.
55:39 at all the buyer innovation here. this is the transgressive faces that over
55:45 the channel fill in. Trump hates across a transgressive erosion surface.
55:52 this may be confused because this does look a little bit course of
55:57 So there's probably a bit of transgressive going on here. Okay, but
56:02 is a This is a non marine . Fill on this is a distant
56:06 faces. So this, actually the across which there is a deepening because
56:10 enormously superimposing a marine, uh, faces overline, a laminated normally mud
56:21 . And so we can contrast the boundary the puts a shallow non marine
56:27 bill sandstone over a marine shale on contrast with the transgressive surface that puts
56:33 marine muddy sandstone over a non Marine this case laminated abandoned Shannon shale.
56:43 of course, the other point that make is is if we if we
56:47 we squeeze down this core photograph, that little kick on the well long
56:55 on that kick on the well log about the same thickness as the thickness
57:01 the line that I used for the . I used to draw the correlation
57:05 , so this transgressive faces is not resolvable on the well off, but
57:11 contact between the flu. If you'll and the overlying mud stone can be
57:17 , notice little graded bed there so this represents a pro gradation, all
57:21 Delta faces that's down lapping onto this faces. That's the maximum flooding surface
57:27 there. And if I want to tradition should always be traditional hair.
57:36 should use the Green Line to mark maximum funding surface. This surface here
57:41 represent the transgressive surface of erosion. , of course, the sequence boundary
57:46 lower down. Okay, next And have a look at this,
57:52 , this section from this intermediate intermediate . This is a lot more complicated
57:58 there is, uh, this is . This area is is kind of
58:02 , what of the main Ansar's It's in this area where the valley
58:05 to be breaking up into distributor So maybe in some sort of a
58:09 hair and yet it's landward of the of the main delta load. So
58:15 is what the core looks like. see evidence of an overall upward course
58:19 high stand on, then a finding , uh, looks like a transgressive
58:26 traditional facing succession. The question where is the sequence Panic here.
58:32 we considered draw our upper coarsening finding with triangles, which is something that
58:38 doing on your well logs. And know what I've done here. And
58:43 should have shown, uh, you , because the width of the triangles
58:47 match. That sort of implies that missing. Okay, if the width
58:52 the triangles match, it means there's missing. So you could sort of
58:55 your triangle, sort of indicate whether not it's, you know, uniform
59:00 coursing, fully preserved versus something's And that indicates kind of a truncated
59:06 coursing. So that's what that's all . So let's have a look at
59:10 high standard. We've seen these faces . Beautiful laminated, uh, mud
59:16 , silk stones and very fine sand . Lots of little graded beds in
59:21 . This funny thing is called a cats, so that's formed by a
59:24 little little storm that hit the Cretaceous . You can see the rocks of
59:28 course of coursing uppers as you go the bottom to the top of the
59:35 on. Then we course it up a sandstone. You notice there's a
59:39 scour surface there with Cem mud stone up classics. There's a pretty obvious
59:46 here, and it separates thes thes bedded sand stones to the cross,
59:53 hair from thes organic rich side, rich kind of clay rich faces that
60:00 like sort of a swampy Bay Phil facing succession. One of the
60:06 Where is the sequence band in Because, of course and upward,
60:10 is the courses faces, and now kind of finding upward. Yeah,
60:17 , these organic, squishy, non faces gradually get a little bit more
60:24 upward. So now you go into into what looks like a sort of
60:28 pro Delta Bay faces with lots of graded beds, and these faces here
60:35 very similar to these faces here so could go back to the Staller faces
60:40 then at the very top. Here have this highly bar debated sandstone overline
60:46 Dunbar debating sentiments. That's kind of weird contact and then above that,
60:52 that defines a transgressive surface that the faces marked with the X and then
60:58 goes into a laminated mud stone that's darker than this faces. So this
61:02 laminated money. This is better to Sandy. Um, so if we
61:08 we take this piece of corn turned , we see beautiful, glossy fragilities
61:12 faces. So that's another transgressive surface erosion. Uh, that that indicates
61:18 this this mud stone was very firm by sharp wall borough. It was
61:25 in, filled by these transcripts, sentiments that fine offers. Okay,
61:30 kind of a little grated. and the very high degree of by
61:35 tells me that this is deposited very . Okay, now, below
61:42 we have this contact here that separates laminated ripple sandstone from these rather
61:48 slightly buyer debated mono specific by, , Nifong here with very thin rippled
61:56 . And this is probably very shallow distribute Terri Bay, Phil.
62:01 Here you can see a very clear between medium grain sandstone and fine grained
62:08 . And so that's the grain size that puts a course of sandstone over
62:13 significant finer sandstone. And so that's I put the sequence boundary.
62:19 that's that contact in the core right . Okay, we can now go
62:24 the most and Delta, Okay? this is what that looks like.
62:31 here we have the base. We a nice black distal pro Delta shale
62:36 represents the distal part of the high . Then there's quite a sharp contact
62:42 . And then there's a big slug deformed sand that looks like some sort
62:45 slump, maybe some sort of storm and indicates the sort of the down
62:52 that that resulted in the beginning of low stand Delta. After that initial
62:58 of slum P sentiments, you get series of horrific faces. Some idiot
63:07 acid and dropped it on the core that that weird feature there is,
63:12 put acid on the core, so message that that's just noise. But
63:16 fairly low. Bar debated. Nice , uh, intimated. Still,
63:20 and sand stones they gradually coursing up into sand stones. There's lots of
63:26 sediment information on ball and pillow. is flame structures in here,
63:32 rip up class. A lot of looking sand stones, Uh, those
63:39 up into parallel laminated sand stones Stances sharp based a lot of inter
63:45 very little bar incubation indicating very high rates once again suggesting a river dominated
63:55 front environment a Z costing upward. get a lot of parallel lamination towards
64:00 top. Some of this stuff may humming Keep ending as a result of
64:06 . Again, somebody put acid on , discovering the core. So this
64:10 not by to Beijing. It's just mark to ask. So what you
64:15 at corporate system that you should just it with water that will prevent these
64:18 the marks. McCurry, Uh, this is the, uh We sort
64:23 saw that in a previous photograph. is the lower down in the core
64:28 right. Next to this. Once , you can see flames structures indicating
64:32 casts a lot of betting of sand operating with Shales. Then here's the
64:37 front. Faces continues to course an , and then eventually we get to
64:43 top that were the more distal position . Now we get a fairly some
64:48 between the upper Delta Front sound stones the overlying marine shales of the next
64:54 the next Paris sequence set. what's interesting is if we look at
65:01 if we look at the sort of just just a delta front and pro
65:06 faces of the high stand, it of low castes on a laminated
65:13 And the low stand consists of low , laminated shale. So we don't
65:18 a big difference in the deposition Between the high stand and low stand
65:23 a big delta is a drop of level, if you will, the
65:26 that that the whole system trips, then it just keeps going.
65:31 So you're like if you're walking downhill you see a little pothole, you
65:36 over it, and then you just on going. So there's no real
65:40 in the deposition environments below and above sequence foundry. Okay, um,
65:48 , uh, and the other thing see, we look at the wheeler
65:52 here. So we're looking at this , Phil, on this low stand
65:58 , we see more detail you there there's there's a condensed section of
66:02 base of the down laughing delta, and there's a massive. The biggest
66:09 break is between the surface of When the delta went past that
66:16 mhm got exposed and then eventually became . You remember? We saw a
66:24 of various surfaces at that point Okay? And so there's that's transgressive
66:32 there on that represents, uh, point right there. Okay. And
66:37 transgressive faces is overlying obey Phil That's the stuff here. And there's
66:43 a gap, so that that's a that's a pretty long strata. Graphic
66:48 there. So the big time gap this part of the strategic graffiti isn't
66:52 transgressive surface of erosion. Okay, ? We're gonna do it zits.
66:57 hour and seven minutes. So since started this lecture, I've told you
67:03 about Allah Member E on this little field trip to the Alberta core
67:10 I'm going to take a break Okay, so we'll we'll stop
67:17 Sharing on. I'm going to Uh . Close it up. Uh,
67:30 . We're gonna take a little break now. Um, I'm gonna stop
67:35
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