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Author Topic:   Origin of the Flood Layers
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 401 of 409 (753648)
03-21-2015 11:40 AM
Reply to: Message 396 by Faith
03-21-2015 12:25 AM


Re: how do you make heat and pressure?
But to reword it I'd say that since the direct lateral pressure was beneath the Paleozoic strata that it was only the rocks beneath that it pushed and tilted and distorted, while pushing up the whole stack above where they all managed to stay horizontal.
Okay, now all you need is evidence. The problem is that we are way ahead of you on that. But please, proceed.

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 Message 396 by Faith, posted 03-21-2015 12:25 AM Faith has not replied

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


(2)
Message 402 of 409 (753657)
03-21-2015 1:29 PM


Just to wrap up some ideas, here is an image of what I see as the planar fabric in the shadowy area beneath the clasts in the photograph that we have been discussing. I have highlighted a few of the features, leaving some to be be seen in the enhanced state that Jon has produced.
There are lots of ramifications here. For one, when you see this material outside of the shadows (in an unenhanced photo), it is a very dark reddish brown. This all compares with the older observations by Sharp (from McKee) discussing a dark, weathered zone at the top of the Vishnu Schist.
I'm pretty sure that the description matches the material in the lower right of this image. the highlighted folia are more likely a soil or clayey zone at the very top of the Vishnu, possibly transported.
Note that the zone is not continuous and does not always occur beneath the quartz-rich pegmatite clasts.
The Vishnu is heavily weathered here. I wanted to try and get the schistosity orientation, but it is just a little to vague for me to feel confident; however in the larger scale picture you could see that the foliations are closer to vertical.
I think you can also see that the larger clast deforms the foliation beneath it. This suggests to me that the clast came to rest in a patch of mud, prior to deposition of the Tapeats.
As a final comment, I refer Faith to an image in Message 272 in which there are boulders of granite and pegmatite suspended in the Tapeats. This is the image that I was thinking about when I called the clasts 'boulders' in an earlier post. It also indicates that there was erosion of the igneous/metamorphic rocks during deposition of the Tapeats.
Edited by Admin, : Change reference to message 272 to a link.

Replies to this message:
 Message 403 by Faith, posted 03-21-2015 4:30 PM edge has replied

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


Message 404 of 409 (753683)
03-21-2015 5:05 PM
Reply to: Message 403 by Faith
03-21-2015 4:30 PM


I see what you are indicating at the bottom of that depression but I really don't know what to make of it. I wish we could send someone to investigate that little trench in person.
Yes Message 272 has the same sort of image of small clasts stuck in and suspended in the sandstone. They are not "boulders," the setting is exactly the same as for the small clasts we've been discussing, even with that little ridge you called a bedding plane. On such a tiny scale I don't see how you could draw such a conclusion from it as "It also indicates that there was erosion of the igneous/metamorphic rocks during deposition of the Tapeats."
According to my browser, there are two pictures in that post.
And I don't expect you to believe anything I write. I post only for people who actually want answers and ideas.

This message is a reply to:
 Message 403 by Faith, posted 03-21-2015 4:30 PM Faith has replied

Replies to this message:
 Message 405 by Faith, posted 03-21-2015 6:27 PM edge has replied

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


Message 406 of 409 (753729)
03-21-2015 7:42 PM
Reply to: Message 405 by Faith
03-21-2015 6:27 PM


The upper picture also appears to be on the same tiny scale.
Just by looking at the size of the channels shown and the grain-size of the granite boulders, I'd say you are wrong.
I will agree, however, that the author is remiss in not having some kind of scale indicator.

This message is a reply to:
 Message 405 by Faith, posted 03-21-2015 6:27 PM Faith has replied

Replies to this message:
 Message 407 by Faith, posted 03-21-2015 7:46 PM edge has replied

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


Message 408 of 409 (753734)
03-21-2015 7:57 PM
Reply to: Message 407 by Faith
03-21-2015 7:46 PM


Note the curved ribbon-like border. It's in all three pictures. The woman has her hand on it in the bottom picture, also the "bedding plane" that makes the ridge behind the border is in all three.
Do you enjoy disagreeing with everything?
I'm saying that the uppermost picture is in a different location than the other two. There is no schist in it - it's all sandstone with some boulders in it.
You can disagree if you want, but I'm done with it. Not everything has to be a federal case. So if you want to spend 8 pages arguing about the shadows, find someone else to play that game.

This message is a reply to:
 Message 407 by Faith, posted 03-21-2015 7:46 PM Faith has not replied

  
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