Summations Only

Thank you.But I didn't get my second question worded as I had intended. I meant to ask:2) What was the cause of the TILTING of the Supergroup?Would you please answer this one?Thanks.Edited by Faith, : No reason given.

I'm not clear which question you are answering. The one about the uplift of the canyon or the one about the supergroup or both in one? Sorry to say I didn't get the one about the Supergroup asked as I had intended.To get a clearer answer, would you answer again?1) What caused the uplift to the Grand Canyon area?2) What caused the TILTING of the Supergroup?Thank you.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Thank you. This raises new questions:a) Did the earthquakes occur before or after the uplifting of the canyon area as a whole?And b) Do you have an explanation for what triggered the earthquakes? Such as tectonic movement? Movement at some different time from that which caused the uplift or what?And thank you for the information about the Shinumo but I can't really process it all. I know about the cliff formation shown by intrusion into the upper layer because of the hardness, but Quartzite IS a metamorphic rock-- metamorphic sandstone, correct? So I keep being puzzled how that particular metamorphic rock occurred in the close company of so much nonmetamorphic sedimentary rock. Takes heat and pressure, right? But it's just one layer in the midst of other layers. Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Sigh, I meant commenting ON the argument I've made. I don't comment on your argument.

Sigh again. You are right that I haven't given any thought to the problems you are posing to me. But unlike those I have been complaining about I have not commented on them either, only to say I'd have to find a way to reinterpret them. But the others here are making judgments about my arguments apparently without having thought about them. OK?The point about not understanding your argument is that I haven't spent time on it because I'm not interested in that facet of the debate. If I found it relevant I'd spend the time. Right now although I'm posting again about things that DO interest me I'm exhausted, not getting enough sleep, making weird mistakes of all kinds, but I want to feel I DID this argument and I'm not at that point yet.

Percy your link that was supposed to go to a message of your own goes to one of mine.

That made me laugh. Doesn't happen too often here. I MUST be tired.

OK, you've answered the question about Supergroup tilting. I'm going to make a collection of the answers I get.But I don't see your answer to question #1 anywhere, about what caused the uplift of the whole canyon area.I'd also ask when they occurred in relation to each other in your scenario, the uplift and the tilting of the Supergroup.Thanks.Edited by Faith, : No reason given.

I don't know if I'll get any more answers to my questions in Message 263 but the answers I've got so far prompt me to ask this:If you look at those cross-sections of the Grand Staircase - Grand Canyon area you can see that the uplift over the GC is in a mounded shape, and that the tilted layers of the Supergroup I've been asking you about occur at the bottom of the canyon area directly under the uppermost height of that mounded area. It looks to me like there is a relation between the uplift and the Supergroup that hasn't been dealt with yet so I would like to get explanations, such asWhen did the uplift occur in relation to the tilting/erosion of the Supergroup?The uplift has been explained as caused by tectonic movement, but Percy has explained the Supergroup in terms of tectonic stretching which is apparently a different thing.I don't have a clear question beyond this at the moment but I'd like you to think about the mounded uplift and the Supergroup beneath it and explain it however you understand it.ThanksEdited by Faith, : No reason given.Edited by Faith, : No reason given.

I understand you share Percy's view of how the tilting of the Supergroup was created, so you've abandoned your earthquake explanation, but I still have the question about when you think the uplift of the whole canyon occurred in relation to the formation of the Supergroup. Since I've asked the same question later on you may have answered it later already.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

(my bolding)Yes. Yes, my argument too, different mechanism and time frame of course from yours, which follows: (my bolding)Question: Is there some relation between the elevating landscape and the Colorado's eroding through it that you haven't spelled out? That is, how did erosion cut through the elevating land to cause the canyon? Seems to me more likely that a relatively small amount of water like the Colorado River would just run off the slopes of the mounding uplift rather than cutting into it. Or if it did cut into it, it wouldn't be in an east-west direction but north-south because that's the direction of the slope.(I've been picturing this mounded area as continuing more or less the entire length of the canyon east-west, so that my illustration of a balloon beneath the area should be a sausage-shaped balloon, and the canyon would have cut lengthwise or east-west through the layers mounded over the balloon or uplift. But again the sloping is north to south, so it's hard to see how a river would have cut east to west.) So the idea you are laying out is roughly this:The Supergroup was formed according to the tectonic stretching that builds range-and-basin mountains, first faulting separating sections of a long block of horizontal layers, then tilting of the separated sections so that they form separated tilted blocks, the tiliting due to the space created by the faulting, so that a sequence of tilted blocks of strata becomes a mountain range.Then after all the layers above were in place -- that according to OE theory accumulated over many millions of years, even a billion or so -- after they were all laid down, then deep processes in the earth raised the entire stack from right beneath the Supergroup into a mound shape, and the strata already laid down above formed that mounded shape right over the Supergroup itself, as can be seen on the cross-sections, the Tapeats or lowest layer sort of draping itself over the Supergroup and all the layers above following suit. And the Colorado River at the top of the mound then began its slow cutting of the canyon east to west (which I question above because of the direction of the slopes.)According to this scenario, the uplift occurred some billion years after the lowest layer over the Supergroup was laid down as it would have taken that long to lay down all the layers up to the Kaibab, and yet it was pliable enough to follow the contour of the uplift without breaking, and so were all the layers that built on top of it. Because as you've argued, even solidly lithified rocks can stretch to that great an extent.That's sort of a slow-motion version of how I'd been thinking about the sequences except I've had the Supergroup tilting / Great Unconformity created at the same time as the uplift. Although I still tend to think that, right now I can't prove it, but at least I am in agreement with you about the basic sequence of things after the formation of the Great Unconformity. Of course I'm highly doubtful that the rocks would have been pliable enough to follow the contour of the uplift after multiple millions of years, and also doubtful that an ordinary river could have cut lengthwise into a mounded sausage-shaped uplift.\ I'll have to see what others have to say about it.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : Sorry for all the edits, just trying to be as clear as possibleEdited by Faith, : No reason given.

Can't picture what you have in mind here, but a river already established would divert AROUND any uplifting of land, not erode through it, and besides, this mounded uplift has a north-south slope, so it's hard to see how water could have eroded the mound east to west. There is apparently an east-west slope down through the canyon now that the river runs down, but the question is how it could have cut in a westerly direction through the upper part of the uplift at all in the first place, right when the uplift was occurring. I'm not sure what rapid runoff you have in mind but if you are referring to my idea that a huge amount of water had to have carved the canyon, I don't explain the meanders or switchbacks as being caused by that initial cataract of water, but by the river that resulted after the great volume of water had decreased to river size. It is rivers that create those formations, not great cataracts of the size I've had in mind that opened the canyon in the first place. I picture that flowing in from all sides of the canyon, not just the eastern end, but there is clearly enough of an east-west slope for the river to run down now.But if you are picturing the river on a flood plain before the canyon existed at all, and attribute the cutting of the canyon to the river's erosive effects as the uplift was occurring, this doesn't seem possible, since the uplift into which the canyon cut is this mounded east-west sausage shape, not to mention that a river would go around any kind of uplift, not through it. So you need an explanation for how that river made its way along the line of the canyon at all, since the slope of the mound where the canyon now is, runs south, not west.By the way I just drew a rather klutzy diagram of what I'm trying to describe, and posted it at my blog (not sure how to post it here) which is HERE . But again, the uplift appears to be in a mound shape sloping north to south, in a sort of sausage shape that extends at least some great part of the length of the canyon east to west, yet the canyon is cut east to west through the south side of the slope, where as I said it looks to me like the water would INTIALLY have had to run south, not west. Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Well, yeah, but water flows into lower channels and a lower channel in the direction of the eventual canyon seems to be precisely what is lacking in this scenario no matter how you reduce the height of the uplift. But I guess we can just assume that it did find a way since there it is at the bottom of the canyon. I just did a quick calculation with a centimeter-to-inches calculator based on a centimeter a year and I get roughly 30 thousand feet per million years so it must have taken a lot of long breaks. Yes, that could work I suppose. Plausible enough based on your OE assumptions, considering that we're all guessing.Edited by Faith, : No reason given.

Yes, apparently everything depends on the slowness of the uplift, and of course at a centimeter per year its height isn't going to offer any appreciable obstacle. Yet the uplift is a MOUND and the canyon is cut into the south side of it along its length so it slopes north-south no matter what its depth. You simply have to assume that the water was already running in that direction anyway and had enough volume so that the rising land really made no difference whatever. I still need to picture a channel for it to seek and I can't find one on the south side of that mound even at a centimeter in height, but I guess that's just me. Water seeks a lower level, it doesn't cut into rising land, UNLESS of course it's a ginormous amount of water that overwhelms everything in its path. Even then it would seek the lowest level to flow in. But a centimeter wouldn't stop it so that takes care of that. [qs]I don't explain the meanders or switchbacks as being caused by that initial cataract of water, but by the river that resulted after the great volume of water had decreased to river size. It is rivers that create those formations, not great cataracts of the size I've had in mind that opened the canyon in the first place. I can't even think about it because It doesn't make enough sense to begin to think about it. The huge volume of water I've thought did the cutting and sculpting of the canyon occurred at the beginning; the river is what was left at the end, so the original cataracts of water did the major work of scouring out the canyon and the river just cut out its own river bed at the bottom of the canyon after all that enormous amount of water had drained away.

Oh and while we're at it, Paul, do YOU think, as Percy does, that strata stacked a mile deep would be pliable enough after a billion years to bend over the contour of that mound over the GC that can be seen in the cross-sections? That continuous long stack of strata that runs north-south from the GC to the GS in both diagrams is a mile deep, and on OE theory the bottom layer (the Tapeats) that is the first layer above the Supergroup is something like a billion years old. Edited by Faith, : No reason given.Edited by Faith, : No reason given.