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Messages - JonF

1
Seems the Mt. Simon is not terrifically uniform.

Facies Analysis of the Late Cambrian Mt. Simon Sandstone in Western Ohio (Midcontinent North America)

Quote
The MSS in DGS-2627 was found to have unique lithological characteristics that make it readily distinguishable from the underlying Precambrian Middle Run Formation and the overlying Cambrian Eau Claire Formation (Figures 3(A) and (B)). Generally, the MSS is a planar laminated or cross bedded, well sorted, subrounded to well rounded, coarseto very coarse-grained, siliceous quartz arenite (Figure 3(C)). There are minor amounts of quartz granule conglomerate, siltstone, and mudstone (Figure 3(D)). Thin mudstone interbeds between sandstones are interpreted as drapes (Figure 3(E)). Observed small-scale sedimentary structures include tidal rhythmites, flaser bedding, lenticular bedding, wavy bedding, and small-scale herringbone cross-bedding. Some larger-scale features can be inferred, such as hummocky stratification, reactivation surfaces, and tidal bundles. Observed biogenic sedimentary structures include Skolithos, Diplocraterion, Arenicolites, and Monocraterion.

...

The contact between the MSS and overlying Eau Claire Formation is gradational over approximately 0.5 m (Figure 4). Within the transition zone, the sediments become finer grained and more intensely bioturbated up core. The contact is well marked by an increase in the gamma-ray log attributed to an increase in shale, glauconite, and K-feldspar content in the lower part of the Eau Claire Formation (Figure 3(B)).In DGS-2627, the stratigraphy of the MSS can be informally divided into three units which were matched to geophysical responses and correlated between wells (Figure 4). The lower unit has a thickness of about 5.7-m and is dominated by packages of finingand thinningupward conglomerate and coarse-grained sandstone. The middle unit is about 16-m thick and is dominated by heterolithic sandstone and mudstone with tidal sedimentary structures and biogenic sedimentary structures. The upper unit is about 47-m thick and is dominated by coarse-grained sandstone with planar lamination, smallscale herringbone cross-bedding, and sporadic escape burrows



Lithofacies in the Mt. Simon Sandstone. (A) Lithofacies T1 (b = burrow); (B) Lithofacies T2, showing tidal rhythmites (tr) and flaser bedding (fb); (C) Lithofacies C1; (D) Lithofacies C2 showing cross-bed sets with normal grading; (E) Lithofacies B1; (F) Lithofacies B2 showing low-angle truncations and reactivation surfaces (rs); (G) Lithofacies B3 showing cross-bedding sets with normal grading (ng); (H) Lithofacies B4 showing burrows (b) Scale bars shown.

And just for grins since there's no chance Davie has gotten this far :



Note the variation in Precambrian lithology. The Middle Run is sandstone. Reality is complex.
2
http://isgs.illinois.edu/ilstrat/index.php/Mt._Simon_Sandstone:



Quote
The Mt. Simon Sandstone, although not exposed, underlies all of Illinois except in local areas where it failed to cover hills on the Precambrian surface. It ranges from less than 500 to 2600 feet thick, with the greatest thickness in northeastern Illinois.
So the ICR article Dave adores so much made at least a 23% error in the thickness range of the magical layer. Excellence in scholarship.
3
Looks as if the Mt. Simon varies quite a bit in thickness, some significantly thicker than 2,000 feet.



https://www.sciencedirect.com/science/article/pii/S1750583616308003
4
Over at Pingu's site, The Skeptical Zone, she wrote ...

Quote
There are plenty of blogs and forums where people with like priors can hang out and scoff at those who do not share them.  There's nothing wrong with those sites, and I've learned a lot from them. But the idea here is to provide a venue where people with very different priors can come to discover what common ground we share; what misunderstandings of other views we hold; and, having cleared away the straw men, find out where our real differences lie.  In my experience, when you reach that point, who is right becomes obvious to both parties.

I highlighted the last part because I agree.

In that spirit ... let's see what common ground we hold with respect to ...

BASAL CAMBRIAN SANDSTONES IN N. AMERICA

I do believe that we all share the belief that ...

1) They are mainly sandstone
2) They were laid down by water
3) There is a lot of sandstone in N. America, perhaps covering 3/4 of the land surface
4) There are different names in different parts of N. Am., Potsdam, Lamotte, Mt. Simon, Tapeats, etc.
5) But each of these names refers to "basal Cambrian sandstone" ... the word "basal" defined previously

Can we all agree to this so far?
I can, tentatively.
Wow. I'm in shock.
Modified to make Voxrat happy. 

I don't think any mainstream scientists think that any basal Cambrian Sandstone is aeolian. Other sandstones higher up, but not basal Cambrian. Also I think Voxrat's comment about different materials underlying these sandstones is incorrect because the very definition of basal Cambrian means that it lies directly on top of Precambrian basement rock.
The nature of which varies.
6
Over at Pingu's site, The Skeptical Zone, she wrote ...

Quote
There are plenty of blogs and forums where people with like priors can hang out and scoff at those who do not share them.  There's nothing wrong with those sites, and I've learned a lot from them. But the idea here is to provide a venue where people with very different priors can come to discover what common ground we share; what misunderstandings of other views we hold; and, having cleared away the straw men, find out where our real differences lie.  In my experience, when you reach that point, who is right becomes obvious to both parties.

I highlighted the last part because I agree.

In that spirit ... let's see what common ground we hold with respect to ...

BASAL CAMBRIAN SANDSTONE IN N. AMERICA

I do believe that we all share the belief that ...

1) It's mainly sandstone
2) It was laid down by water
3) There a lot of it in N. America, perhaps covering 3/4 of the land surface
4) It is named differently in different parts of N. Am., Potsdam, Lamotte, Mt. Simon, Tapeats, etc.
5) But each of these names refers to "basal Cambrian sandstone" ... the word "basal" defined previously

Can we all agree to this so far?
I can, tentatively.

SFW?
7
Spoiler (click to show/hide)
I'll Grant you I first learned about them from icr.

Well, for some value of "learned" I guess.  You certainly read about them there.  But not even ICR bothers to point out that there are allegedly TWO of these extraordinary pancakes, probably because they hope the punters won't read both articles and notice that they are talking about two quite different strata.

But I learned the specifics of the layer that I'm now interested in - the cambrian basal sandstone - from various mainstream articles on the internet presumably based on geological texts. 

And the "specifics" as you call them don't actually support ICR's claim. And ICR knows this too. So they accuse the geologists of being "provincial". Which is obvious bullshit.  If geologists were "provincial", there would be no talk of Cambrian or Ordovician or Silurian etc layers, no talk of mega sequences, no maps of the N.American craton - the very ones you posted.

So stop dispensing squid ink and schaff and flares and deal with what I've actually posted.

no u
Quote
Coward.
Spoiler (click to show/hide)
if they were not being provincial, then they would give the single basal sandstone layer a single name instead of 20 different names.

There is no single layer. Your spectacular failure to produce any evidence for your claim is obvious.

Afdave's Third Law
: If you have an objection to any point I've raised, I've already addressed it. No, I won't tell you where.
You don't have to call it a "single layer" if you don't want to.

However ...

You cannot escape the facts that ...

1) "Cambrian" sandstone lies atop "Pre-Cambrian" basement rock in much of N. America
2) This sandstone (whether multiple layers or a single layer) varies in thickness from approx 100 ft to 2000 ft
3) Nothing I've read indicates that there is any definitive demarcation between say the "Lamotte" sandstone and the "Mt. Simon" sandstone.  It's certainly not state lines as Voxrat pointed out.  It's not gremlins with swords.

So that's the data that we have ... the question is ... what do we make of it?
I still disagree on the thickness.

Nothing you have posted indicates that there is no definitive demarcation. Nothing you have posted even addresses the question of demarcation.

One layer is pretty much all of your fantasy consists of. Lose that and we are not discussing one fludde. I see you have abandoned your feeble and pathetic events to support it.

Howzabout we get on topic and you post some evidence for a global fludde? Your one layer hallucination isn't such.
8
Spoiler (click to show/hide)
I'll Grant you I first learned about them from icr.

Well, for some value of "learned" I guess.  You certainly read about them there.  But not even ICR bothers to point out that there are allegedly TWO of these extraordinary pancakes, probably because they hope the punters won't read both articles and notice that they are talking about two quite different strata.

But I learned the specifics of the layer that I'm now interested in - the cambrian basal sandstone - from various mainstream articles on the internet presumably based on geological texts. 

And the "specifics" as you call them don't actually support ICR's claim. And ICR knows this too. So they accuse the geologists of being "provincial". Which is obvious bullshit.  If geologists were "provincial", there would be no talk of Cambrian or Ordovician or Silurian etc layers, no talk of mega sequences, no maps of the N.American craton - the very ones you posted.

So stop dispensing squid ink and schaff and flares and deal with what I've actually posted.

no u
Quote
Coward.
Spoiler (click to show/hide)
if they were not being provincial, then they would give the single basal sandstone layer a single name instead of 20 different names.

There is no single layer. Your spectacular failure to produce any evidence for your claim is obvious.

Afdave's Third Law
: If you have an objection to any point I've raised, I've already addressed it. No, I won't tell you where.
9
Guys...

We agree that this basal Sandstone was deposited by water.

We agree that it was a single Marine transgression which deposited it.

no we don't.  Please look at an elementary geology textbook, Dave.


We just disagree on how long it took.

That's all.

We disagree on what's even there, Dave, let alone on what caused it.  There is no single vast incredibly flat layer of sandstone, let alone two.
if you don't think we agree on this then your head is up your butt. Go study some basic geology.

Dave, the ONLY reason you think there are (two now) "vast incredibly flat layer{s} of sandstone" covering much of North America is because you read it in those two (mutually contradictory in fact) ICR articles.  You didn't read it in a "basic geology" text book.

You read it in those ICR articles.  Go study a basic geology text book.  Or even watch what you arrogantly called a "propaganda video" - it shows how repeated regressions and transgressions create sandstone formations.  From that, you might be able to figure out what this diagram is about:



and why ICR is full of shit.
I'll Grant you I first learned about them from icr. But I learned the specifics of the layer that I'm now interested in - the cambrian basal sandstone - from various mainstream articles on the internet presumably based on geological texts. 

You haven't posted quotes or links from any source[1] containing evidence supporting your claim.

Look at the vague and laughable list of agreements you just posted. Not bounded by Missouri borders. One formation covers a lot of the Southwest.

Quote
So stop dispensing squid ink and schaff and flares and deal with what I've actually posted.

We have dealt with what you really posted.
Other than ICR.
10
Guys...

We agree that this basal Sandstone was deposited by water.
We don't agree on what "this basal Sandstone" even is.
we agree that it's sandstone. We agree that it was deposited by water. We agree that it sits atop so-called pre-cambrian basement. We agree that it's not demarcated by Missouri state lines. Or Gremlins with swords. We agree that varies in thickness between a hundred feet and 2000 feet. We agree on certain other things such as that the one area of it that geologists call the Mount Simon Sandstone covers a fairly significant portion of the midwestern u.s.

And there's probably more we agree on.
I don't agree on the thickness.

None of that is evidence all the sandstone is one layer.
11
And why is it* supposed to be significant? I really don't think Dave knows the answer to that question because neither of the ICR articles provide it. They just state it like it's supposed to be significant and then proclaim based on no provided evidence or reasoning that it must be the work of a global flood rather than normal sedimentary processes.

* the alleged uniformity of the allegedly "incredibly thin" and allegedly "super duper flat" alleged single sandstone layer allegedly covering all much of the planet North America.

Yes. I have been asking this for days. I've gotten the
Afdave's Fourth Law:
 Unanswerable questions are invisible.

treatment.  I predict you will, too.

I've answered this over and over. The reason it would be significant is because there are no known processes operating today which could possibly produce such a layer if extrapolated to millions of years.
But this objection has been rebutted over and over:
1. It's nothing more than an unsubstantiated Argument from Incredulity.
2. Even if it were substantiated - we wouldn't expect the same processes to operate in all periods of the earth's history.
Particularly not a world where all the land was lifeless desert.

model it. Should be easy for you since you are so brilliant. Model a land mass with no plants, just bare rock. Then model a transgression of the sea over several million years and see what you get.  I predict you will get nothing remotely resembling a 2 million square mile ultra thin Ultra flat layer of sandstone.

And I make that prediction with half my brain tied behind my back with no more intelligence than that necessary to find my way out of a brown paper sack.
Walther's law predicts thin flat sandstones covering vast areas under appropriate sea level conditions. Such as near-constant-rate transgression/regression

There is no two million square miles of one thin flat sandstone.

Your demand to see a duplicate forming today is irrelevant to what known processes can do.

I see you make that prediction with no consideration of reality.
12
Guys...

We agree that this basal Sandstone was deposited by water.

We agree that it was a single Marine transgression which deposited it.

no we don't.  Please look at an elementary geology textbook, Dave.


We just disagree on how long it took.

That's all.

We disagree on what's even there, Dave, let alone on what caused it.  There is no single vast incredibly flat layer of sandstone, let alone two.
if you don't think we agree on this then your head is up your butt. Go study some basic geology.
<Dave enters full random flailing mode >
13
And why is it* supposed to be significant? I really don't think Dave knows the answer to that question because neither of the ICR articles provide it. They just state it like it's supposed to be significant and then proclaim based on no provided evidence or reasoning that it must be the work of a global flood rather than normal sedimentary processes.

* the alleged uniformity of the allegedly "incredibly thin" and allegedly "super duper flat" alleged single sandstone layer allegedly covering all much of the planet North America.

Yes. I have been asking this for days. I've gotten the
Afdave's Fourth Law:
 Unanswerable questions are invisible.

treatment.  I predict you will, too.

I've answered this over and over. The reason it would be significant is because there are no known processes operating today which could possibly produce such a layer if extrapolated to millions of years.

Sure there are.
Fine. Show me a shoreline anywhere in the world where this type (size, thinness, flatness) sandstone layer is forming today.

You're going to have to get a lot more specific than "hey Dave ever been to a beach?"
Moving the goalposts. The issue is whether or not known processes could create what we see in stratigraphy. Aside from the obvious difficulty in identifying such a layer without watching it for millions of years, what known processes can or cannot do does not depend on whether or not they are doing it today.

You have no answer for the real question.
14

Guys...

We agree that this basal Sandstone was deposited by water.

We do not agree that the formations are one. As usual, you have been spectacularly incompetent at producing evidence for your claim.

Quote
We agree that it was a single Marine transgression which deposited it.
We do not agree. You just looked at the maps and assumed they tell the entire story. [/size]
15
I'm suggesting that there is an extremely large layer in North America. I'm guessing perhaps  two or three million square miles in areal extent. And at the moment I'm trying to get more accurate information about it by piecing together all these various names of basal Cambrian sandstones.
There is no evidence that all "basal Cambrian sandstone" is one layer. You have posted some evidence strongly suggesting they are not one layer.
sure there is. Even you say that it was one Marine transgression that deposited it.  Look again at your own geologic Evolution Maps which I posted.
They do not show all transgressions and regressions.

A Chronological Survey of Sedimentary Landforms in the Continental United States/Cambrian:

Quote
During Cambrian time, shallow epeiric seas covered large portions of the continent. The general trend was toward increasing depth and areal extent of these seas, but there were also numerous episodes of retreating seas as land masses were uplifted by tectonic forces. The Sauk Sequence is, therefore, typically interfingered with units grading laterally into each other, and sequence repetitions are abundantly present. For any given shoreline position, the sequence nearest shore consists of light colored sands, silts, and muds, sometimes containing thin limestone bands. Farther out, pure limestones and dolomites accumulated. Then, in the deeper waters farther offshore, dark colored silts, muds and sands, and impure limestone beds that contain chert are found. It is important to realize that these interlaced facies do not represent different times of deposition, but merely different environments. Thus, in the basal layers of the Grand Canyon, we see the Lower Cambrian Tapeats Sandstone being deposited near shore, grading to the eastward into the Bright Angel Shale, which in turn grades into the Muav Limestone. The Bright Angel Shale is a classic example of a formation that represents different intervals of deposition at different places. Because the trend of Sauk transgression in this region was from west to east, the Bright Angel Shale follows this path laterally with respect to time. Thus, in the westernmost exposures, the Bright Angel Shale is partly of Lower Cambrian age, while the easternmost exposures are entirely Middle Cambrian.

The transition from sandstone to shale to carbonates is the classic signature of a transgressive event. Regressive events may show the reverse sequence, if the regression was also a slow event. (Some regressions were the result of rapid crustal movements, and did not allow time for the sedimentation to occur). If an uplifted region became exposed to erosion at any time, there may also be missing sequences and a visible unconformity in the bedding.
The only evidence you have posted on the issue of "one layer" is from the Wikipedia articles on the Potsdam and Mt. Simon formations. Each article briefly discusses equivalence and correlation but does not mention the other, strongly suggesting there is no correlation or equivalence between the two. The Mt. Simon article says it is the basal unit in the Potsdam Group; the group is named after the Potsdam sandstone but I can't find a definitive answer whether the entire group is the Potsdam sandstone or the Potsdam sandstone is one part of the Potsdam group[1]. If the latter, then the Mt. Simon is not the same as the Potsdam sandstone.

All your other posts are personal incredulity[2] or laughably ignorant fantasies and misunderstandings[3].
Sources differ.
Which is not evidence.
Not valid evidence.
16
I'm suggesting that there is an extremely large layer in North America. I'm guessing perhaps  two or three million square miles in areal extent. And at the moment I'm trying to get more accurate information about it by piecing together all these various names of basal Cambrian sandstones.
There is no evidence that all "basal Cambrian sandstone" is one layer. You have posted some evidence strongly suggesting they are not one layer.
17
So back to my original question.

We have this basal Cambrian Sandstone, right? It has various names in various parts of N. Am. ... Mount Simon, tapeats, lamotte, Potsdam, Etc.  Do we all agree that this is basically a single formation all formed by a single Marine transgression?
No.

You have presented no evidence that they are all the same formation.  You have presented evidence that strongly suggests they are not.

You have not presented any evidence of any number of transgressions.
18
You guys are starting to ask some great questions.

But the first question needs to be "is there a very large very flat very thin sandstone layer sitting atop the pre-cambrian basement pretty much all over the world?
No.

Interesting jump from much of North America to all over the world.
19
The Jordan sandstone is late Cambrian (Croixian, https://www.researchgate.net/publication/249525610_Deposition_of_the_uppermost_Cambrian_Croixan_Jordan_Sandstone_and_the_nature_of_the_Cambrian-Ordovician_boundary_in_the_Upper_Mississippi_Valley). The Lamotte sandstone is Silurian (https://ngmdb.usgs.gov/Geolex/UnitRefs/LamotteRefs_2391.html). Clearly different. Neither lies on PreCambrian basement.

Weren't we discussing Cambrian formations only?
20
And, dammit, the fact that geologists actually call rocks "Cambrian" even when they are found in North America!
:sosmug: Dave won't get it.
21
In other words, just because we call it the Lamotte sandstone in Missouri and we call it the Jordan sandstone in Iowa ( next state north of Missouri ) does not mean that they are different formations.
We know that. It also does not mean they are the same, especially when they differ in composition or other significant ways. We also know that the evidence you have posted so far strongly indicates the Mt. Simon sandstone and the Potsdam sandstone are indeed different formations. You haven't tried with any other formations.

24
In my never-ending quest to get you guys to use your own brains independently instead of submitting to groupthink, let me ask you a question ...

The lamotte sandstone. (Just to pick one which you guys think is of Cambrian age)

Here's a random abstract that says it covers all of Missouri ...
Quote
Abstract
The Lamotte Sandstone, the basal Cambrian sedimentary rock unit continuous throughout Missouri, was investigated as a potential unit for shallow geologic carbon sequestration.  https://bearworks.missouristate.edu/theses/2166/

Do you guys think that this means that it just ends at the borders of Missouri? Or what?
You're the one doing the research and pushing your fantasy.

You tell us what it does based on.....

EVIDENCE.
25
Evidence, Davie-dork.