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Faith  Suspended Member (Idle past 1640 days) Posts: 35298 From: Nevada, USA Joined: |
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Author | Topic: Origin of the Flood Layers | ||||||||||||||||||||||||||||||||||
edge Member (Idle past 1901 days) Posts: 4696 From: Colorado, USA Joined: |
OK, fine, I will hold my theory alone then that magma intruding into rock rubble could transform it into schist, especially with the added pressure of the enormous weight of three miles of strata above it. However it happened, though, the mere presence of granite in the schist shows the presence of enough heat from magma in the general vicinity to fry the stuff.
I'm sure you would know.
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Faith  Suspended Member (Idle past 1640 days) Posts: 35298 From: Nevada, USA Joined: |
As to the burial origin of the foliation, if that is due to the Paleozoic section being deposited, then the foliation should be closer to vertical. In fact, IIRC, there are some folds in the schist, which would suggest some kind of lateral compression. Tectonic pressure is usually lateral isn't it? That's what I attribute the whole scenario to, the Kaibab uplift, the tilted Supergroup, the formation of Vishnu and granite, the erosion between unconformity and Tapeats caused by sliding of the Supergroup etc. In my scenario all the strata above is present three miles deep and then the upper two miles above the Permian broke up due to the uplift also. Heat from below, pressure from above and from the side both.
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Faith  Suspended Member (Idle past 1640 days) Posts: 35298 From: Nevada, USA Joined: |
I'm putting together my own hypothesis, it is subject to change but not on the basis of everything you guys throw at me. So you can stop with your "you would know" jibes.
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edge Member (Idle past 1901 days) Posts: 4696 From: Colorado, USA Joined: |
No it wouldn't. The magma intrusion baked whatever it was into schist.
Actually, just baking the rocks would not create a schistosity (foliation) in the metamorphic rocks. And there is no indication of dynamic (deforming, such as folding) related to intrusives visible in the GC.
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edge Member (Idle past 1901 days) Posts: 4696 From: Colorado, USA Joined: |
Tectonic pressure is usually lateral isn't it?
No. For instance, we don't see compressional folding in the Paleozoic rocks.
That's what I attribute the whole scenario to, the Kaibab uplift, the tilted Supergroup, the formation of Vishnu and granite, the erosion between unconformity and Tapeats caused by sliding of the Supergroup etc.
Then you would be wrong on several accounts.
In my scenario all the strata above is present three miles deep and then the upper two miles above the Permian broke up due to the uplift also. Heat from below, pressure from above and from the side both.
There's not enough horizontal stresses to fold the Paleozoic rocks, but the metamorphic sequence is severely deformed. That means that you are wrong before you get out of the starting gate.
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Faith  Suspended Member (Idle past 1640 days) Posts: 35298 From: Nevada, USA Joined: |
This is easily resolved by figuring that the tectonic pressure, while lateral, occurred BENEATH the level of the Paleozoic rocks, therefore only affecting the basement rocks -- or I shouldn't say "affecting" since I think the whole area was affected as it also caused the Kaibab uplift. 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.
Edited by Faith, : No reason given. Edited by Faith, : No reason given. Edited by Faith, : No reason given.
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JonF Member (Idle past 363 days) Posts: 6174 Joined: |
And no, I'm seeing the clasts and the depression correctly, you aren't. Infallible in everything, not just the Bible, hum? Edited by JonF, : No reason given.
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JonF Member (Idle past 363 days) Posts: 6174 Joined: |
The edge even has a slight bevel to it, Point it out.
the inner border is way too sharp to be a shadow. Also that shadow is just way too dark, showing no features at all of the supposed surface that would have to be there. Shadows in bright sunlight have sharp edges.
Also that shadow is just way too dark, showing no features at all of the supposed surface that would have to be there. Yet even the vertical edge the clasts are stuck in, which is in shadow itself, is so light it would reflect light enough to pick up features in that dark shadow even in the original photo, if it really was a shadow on the same level, but that is not the case. All this is so obvious I see I can't trust anything you say about a photo image. BS. Obviously you don't know anything about dynamic range in photographs. I do. The HDR picture I posted shows that the shadowed area is illuminated, showing features within. The original image didn't have the dynamic range required to Of course, in your scenario the bottom of the "depression" wold be illuminated in the original picture.
Then tyou go on to outline in green a part of the higher surface on the bottom left along with the lower shadow in the depression, claiming they are on the same surface. Sheesh, this is ridiculous. The features in the shadow are obviously extensions of the features in the light, as my ellipses indicate.
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JonF Member (Idle past 363 days) Posts: 6174 Joined: |
Actually, I pointed this our well before Percy did. I mentioned that the larger image with the geologist was from the exact location of the original picture that you posted. Yes, you did.
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jar Member Posts: 34140 From: Texas!! Joined: Member Rating: 7.1 |
Faith writes: Even geologist edge didn't say it was completely out of the question that the magma could have caused the schist, though he gave some technical reasons why he doesn't think that is what happened. No, he said that the evidence shows it was not the magma intrusions.
Faith writes: And it's the COMBINATION of the heat from the magma PLUS the enormous weight of the three-mile stack of strata above that I proposed were the two factors that turned the original rock into schist. So you are including some three miles of material above the Vishnu Schist to turn the mudstone or shale into schist. That is five as long as you can provide the model, method, process, procedure or mechanism that explains the creation of each layer in that three mile expanse of material.
Faith writes: "Common source of heat for all the schist?" I believe that is plentiful wherever there is schist in the canyon because granite is usually associated with it. I was trying to at least give you a chance but you just make your position weaker and weaker. Now you want to also add the Zoroaster Granite. So you will also need to present the model. method, process, procedure or mechanism that creates the Zoroaster Granite. Now it happen to be younger than the Vishnu Schist. But remember, schist and granite and sandstone are different things.Anyone so limited that they can only spell a word one way is severely handicapped!
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edge Member (Idle past 1901 days) Posts: 4696 From: Colorado, USA Joined: |
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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edge Member (Idle past 1901 days) Posts: 4696 From: Colorado, USA Joined:
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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.
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Faith  Suspended Member (Idle past 1640 days) Posts: 35298 From: Nevada, USA Joined: |
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."
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edge Member (Idle past 1901 days) Posts: 4696 From: Colorado, USA Joined: |
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.
According to my browser, there are two pictures in that post.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." And I don't expect you to believe anything I write. I post only for people who actually want answers and ideas.
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Faith  Suspended Member (Idle past 1640 days) Posts: 35298 From: Nevada, USA Joined: |
The upper picture also appears to be on the same tiny scale.
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