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Author Topic:   Evolution. We Have The Fossils. We Win.
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(2)
Message 1312 of 2887 (829675)
03-11-2018 11:46 PM
Reply to: Message 1311 by Faith
03-11-2018 11:36 PM


Re: A knife-edge thick contact is NOT an inch thick
This is very much the same interpretation of the sand in the Hermit cracks that a member of Paul Garner's British creationist team is pursuing.
That's fine with me.
I'm sure they've already got their conclusions drawn.
Edited by edge, : No reason given.

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 Message 1311 by Faith, posted 03-11-2018 11:36 PM Faith has not replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(2)
Message 1319 of 2887 (829684)
03-12-2018 9:00 AM
Reply to: Message 1313 by Tanypteryx
03-12-2018 1:06 AM


Re: A knife-edge thick contact is NOT an inch thick
When you say the the base of the Coconino liquified, do you mean it changed behavior and started acting like a liquid due to earthquake vibration?
That is what people are saying and it is supported by the apparent alignment of the fractures with active fault systems such as the Bright Angel.
Another question this brings to mind, can sandstone form relatively near the surface and without the extreme pressure that we normally see sedimentary rock being subject to?
Well, loose sands can have some cohesion due to moisture, but this doesn't give the material real strength. It allows us to build sand castles.
I am just trying to understand the lithification process that captures the cross bedding of sand dunes.
Evidently, it can take a long time for sand to lithify if there is no cementing material in the groundwater. Unfortunately, I am not a sedimentologist, so I'm guessing.
Can water passing through the sand initiate a chemical reaction that results in a solid mineral matrix filling some of the space between sand graines?
Certainly. A lot of the eolian sands are not well cemented, however, and that is why they develop the landscapes that we see. I think that sheer pressure may make a big difference in the formation of stronger rock by producing a silica cement.
Maybe more later.
I might add that this all has nothing to do with the age factor. There are lots of rapid events in geological time.
One last note. I'm wondering if the first layer of sand at the base of the Coconino was actually laid in water. That is pretty common.

This message is a reply to:
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edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(2)
Message 1320 of 2887 (829685)
03-12-2018 9:05 AM
Reply to: Message 1318 by Faith
03-12-2018 8:38 AM


Re: A knife-edge thick contact is NOT an inch thickEros
The evidence is what you see when you look at the surface of the earth now. It looks nothing like what we see between layers of the geo column.
That is because you equate the geological column with the Grand Canyon strata which were marine deposits.
So, obviously, you could not see them.

This message is a reply to:
 Message 1318 by Faith, posted 03-12-2018 8:38 AM Faith has replied

Replies to this message:
 Message 1321 by Faith, posted 03-12-2018 9:08 AM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1345 of 2887 (829733)
03-12-2018 9:17 PM
Reply to: Message 1321 by Faith
03-12-2018 9:08 AM


Re: A knife-edge thick contact is NOT an inch thickEros
The Mesozoic and Cenozoic layers look exactly the same and in fact there are lots of very tight contacts there.
To the untrained, yes.
There are 'tight' contacts everywhere. What are you saying?

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edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1346 of 2887 (829734)
03-12-2018 9:42 PM
Reply to: Message 1331 by Percy
03-12-2018 1:33 PM


Re: A knife-edge thick contact is NOT an inch thick
Well, this is different. What would have happened to the top of the Hermit during the seismic events?
Not sure. This is new to me though I've traced some references back to the late 60's. I have seen sandstone dikes cutting into shaley units suggesting that the sandstone is not yet lithified. Never thought too much about it. If the cracks are as geometrically related to the Bright Angel fault as they say (and knowing the source, that's a big 'if') it's pretty compelling evidence for liquefaction and injection.
Does this have anything to do with the inch-wide something?
Probably not.
Do you no longer think the Coconino sand penetrations into the Hermit were mud cracks?
My mind is open. I have some reservations, but realistically it has no effect at all on the age of the rocks.
Also, I looked up the Bright Angel Fault but couldn't find anything about whether there was slippage along the fault during deposition of the Paleozoic layers, something Faith would be interested in since she believes the region completely tectonically quiescent during the period.
My understanding that it is an old fault, possibly going back to the Proterozoic. It is supposedly active now.
I have a lot of questions about this whole thing that might only be answered by a field trip to the site.
For one thing even Whitmore mentions that fragments of lithified Coconino are present in the area of alleged liquifaction. That argues against the young earth position.
It's all very complex and will take some time to digest. I have a very smart friend who did a senior thesis on clastic dikes. I might contact him.
My current theory is that the base of the Coconino was not completely lithified due to groundwater combined with a lack of cementation, and temporary seismic over pressures might have resulted in injectites. In fact this is one of the possible reasons that large-scale crossbeds in sandstones are lost ... liquefaction, slumping and bioturbation.
By the way a lot of the old literature shows that things are pretty complex. For instance, the other week I saw a layer in the Cutler Formation that looked like little box garden of flat, waterlain sediments with organic material in it... probably a small oasis, if you will. Sand dunes are more complex that one would think But that's one more reason that I don't necessarily trust Whitmore.

This message is a reply to:
 Message 1331 by Percy, posted 03-12-2018 1:33 PM Percy has replied

Replies to this message:
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edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 1347 of 2887 (829735)
03-12-2018 9:48 PM
Reply to: Message 1337 by Faith
03-12-2018 3:34 PM


Re: A knife-edge thick contact is NOT an inch thickEros
Of course paleosols were transported, and root systems, no problem with those. Your language conjures up a whole intact termites' nest but all these things are usually just the bits and pieces I'm talking about, not whole anythings. And dinosaur nests too are usually just smashed flattened remnants yet they get described as if they are intact, just the way a fossilized leaf and a fossilized creature become whole exotic landscapes with trees and animals of a particular "time period."
Faith, have you ever see what waves do to soil?
Truly? You expect to pick up termite nests and move the along with dinosaur nests and tracks to another location?
Sorry, no buying.

This message is a reply to:
 Message 1337 by Faith, posted 03-12-2018 3:34 PM Faith has replied

Replies to this message:
 Message 1348 by Faith, posted 03-12-2018 9:56 PM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 1349 of 2887 (829737)
03-12-2018 10:18 PM
Reply to: Message 1348 by Faith
03-12-2018 9:56 PM


Re: A knife-edge thick contact is NOT an inch thickEros
Once I know the Flood happened and that the strata were the result I also know that whatever is found IN the strata was deposited by the Flood. How it happened I don't know and don't care once I know the Flood did it, and I do.
Nothing like having an open mind, yes?

This message is a reply to:
 Message 1348 by Faith, posted 03-12-2018 9:56 PM Faith has replied

Replies to this message:
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edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1406 of 2887 (829849)
03-15-2018 8:56 AM
Reply to: Message 1405 by PaulK
03-15-2018 12:59 AM


Re: Tilt then fault, or fault then tilt, or...
Is it ? Once the fault is there the sections can move at least semi-independently. The force can produce motion along the fault rather than simply being transmitted to the other section.
Moose is talking only about the timing of the tilt versus the fault. From the information shown, all we can say is that the bedding is older than the fault, which in turn is older than the unconformity. This is based on the principle of cross-cutting relationships that says if one structural element disrupts another one, it is the younger of the two.
We can't say anything for certain about the relative timing of faulting and tilting. However, my prejudice in this case would be that they occurred at the same time because that is common in extensional tectonic settings.
Edited by edge, : No reason given.

This message is a reply to:
 Message 1405 by PaulK, posted 03-15-2018 12:59 AM PaulK has replied

Replies to this message:
 Message 1407 by Faith, posted 03-15-2018 2:25 PM edge has replied
 Message 1408 by PaulK, posted 03-15-2018 3:15 PM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1411 of 2887 (829868)
03-15-2018 10:00 PM
Reply to: Message 1408 by PaulK
03-15-2018 3:15 PM


Re: Tilt then fault, or fault then tilt, or...
I guess I just don’t understand the mechanics of it. That the tilt is at the same angle makes a lot of sense to me if the fault occurred later, or at the very end of the tilting event. But if the fault was there I can’t figure out why there wouldn’t be any slippage at the fault that would see one side tilted more than the other.
Sure, that could happen. Depends on fault geometry and the degree of offset.
Remember, this is, in large part, a schematic section, so it could as well be true here.
And all that I think Moose was saying is that you cannot tell if the fault came first or the tilting. We truly cannot tell from this diagram.

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edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1412 of 2887 (829869)
03-15-2018 10:10 PM
Reply to: Message 1409 by PaulK
03-15-2018 3:32 PM


Re: Tilt then fault, or fault then tilt, or...
Edge and Moose think it is related to the tilting of the Supergroup. So there is an alternative possibility there. And there doesn’t seem to be any upper resistance that would vary enough to cause the fault, as well as the evidence of cross-cutting which shows that the fault occurred before the upper strata were there at all.
Right. Even if the Shinumo were thrust into the Tapeats (all the way through, actually) there should be some differential movement between it and the Hakatai and the Dox, since they do not penetrate the Tapeats.
The faults that offset the Supergroup Rocks is cut by the unconformity, as are the various intrusive bodies in the Precambrian rocks. The dikes are cut off and the granite plutons are cut off by the unconformity.
But to top it all off, there are erosional gravels derived from the Supergroup and the Vishnu rocks at the base of the Tapeats Sandstone. This is the drop-dead argument against Faith's upthrust of the Shinumo. The rocks were hard enough to form erosional gravels and dot no exhibit a shear texture that would be necessary in Faith's scenario.

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Replies to this message:
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 Message 1416 by Faith, posted 03-15-2018 11:04 PM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1413 of 2887 (829870)
03-15-2018 10:16 PM
Reply to: Message 1407 by Faith
03-15-2018 2:25 PM


Re: Tilt then fault, or fault then tilt, or...
So in this view the fault and the tilt were simultaneous, The Supergroup was being pushed up into the Tapeats and pushed horizontally under the Tapeats as well (the distance of a quarter mile, which is how far the quartzite boulder embedded in the Tapeats traveled from its origin in the Shinumo.) The forces split the Supergroup, its upper edges were eroded off, and the movement that caused the erosion stopped the fault line where the Supergroup met the Tapeats. That's why the "step" is simply removed and didn't penetrate into the upper strata.
I like it. What do you think?
You do understand that the Canadian Rockies topography that you see is formed by erosion, do you not?
Do you understand what I'm saying here?

This message is a reply to:
 Message 1407 by Faith, posted 03-15-2018 2:25 PM Faith has replied

Replies to this message:
 Message 1414 by Faith, posted 03-15-2018 10:53 PM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1418 of 2887 (829875)
03-15-2018 11:37 PM
Reply to: Message 1416 by Faith
03-15-2018 11:04 PM


Re: Tilt then fault, or fault then tilt, or...
Yes, cut off by the unconformity. That's part of the evidence that the strata above were already there when these events occurred: the faulting, the tilting, the granite and Vishnu formation, the erosion etc, and that is evidence for the occurrence of the tectonic force in the "Precambrian" rocks after all the strata were in place.
The unconformity cuts both the bedding of the supergroup and the fault that offsets it. It does not cut the Paleozoic sedimentary rocks.

This message is a reply to:
 Message 1416 by Faith, posted 03-15-2018 11:04 PM Faith has replied

Replies to this message:
 Message 1420 by Faith, posted 03-15-2018 11:39 PM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1419 of 2887 (829876)
03-15-2018 11:38 PM
Reply to: Message 1414 by Faith
03-15-2018 10:53 PM


Re: Tilt then fault, or fault then tilt, or...
No I don't know what you mean by "formed by erosion." I was focused only on the form of the strata.
They were formed by erosion just as the shape of the Supergroup rocks was.

This message is a reply to:
 Message 1414 by Faith, posted 03-15-2018 10:53 PM Faith has replied

Replies to this message:
 Message 1423 by Faith, posted 03-15-2018 11:42 PM edge has not replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1421 of 2887 (829878)
03-15-2018 11:40 PM
Reply to: Message 1415 by Faith
03-15-2018 10:56 PM


Re: Tilt then fault, or fault then tilt, or...
Erosion will do for my scenario, don't need shearing. But what do you mean by "at the base of the Tapeats?" IN the Tapeats or below it? Offhand "derived from the Supergroup and the Vishnu" sounds like a confirmation of my scenario.
So you agree that erosion of the Supergroup occurred before the Tapeats was deposited on the unconformity?
How do sedimentary clasts of the Supergroupat the base of the Tapeats support your position?

This message is a reply to:
 Message 1415 by Faith, posted 03-15-2018 10:56 PM Faith has replied

Replies to this message:
 Message 1424 by Faith, posted 03-15-2018 11:47 PM edge has not replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 1422 of 2887 (829879)
03-15-2018 11:42 PM
Reply to: Message 1420 by Faith
03-15-2018 11:39 PM


Re: Tilt then fault, or fault then tilt, or...
That is correct. What's your point?
The unconformity is younger than the Supergroup and the faults that offset it.
But there is no evidence that it is younger than the Tapeats.

This message is a reply to:
 Message 1420 by Faith, posted 03-15-2018 11:39 PM Faith has replied

Replies to this message:
 Message 1425 by Faith, posted 03-15-2018 11:55 PM edge has not replied

  
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