Evidence that the Great Unconformity did not Form Before the Strata above it

Let's put it this way:The evidence that you provide is not diagnostic of your explanation. It is also explained by mainstream interpretations. And, frankly, the mainstream interpretations are better because they respect other evidence such as the lack of shearing on the GU contact. I would still call that a lack of evidence because you have ignored evidence that you cannot explain. I'm sorry but sheer stubbornness does not impress me. You are wrong here. I have acknowledged that the sediments were soft when they took on the appearance of draping. The problem is that this is as far as you get. You have nothing going beyond that. Typically, the forces that produce a feature, will at least have the same symmetry in different locations or in different rocky types; especially considering that you recognize only one tectonic event recorded in the stratigraphic history of the planet. Which is irrelevant because erosion can occur quickly in a geological sense. Glaciers can plane off a continent in a geologically short period of time. So, you see how your evidence is not supportive of your theory. It is not effective evidence. Actually not. We have provided you with alternative explanations that honor the other aspects of the roadcut, such as the lack of shearing. My experience with laymen conducting experiments in sedimentation do not give me much confidence that you can do this. But we shall see. Your saying this to an idyot like me does not carry much weight.

One problem you have here is that the 'disruption' you see is due to fracturing. If the rocks were deformed while soft, as you purport, then there should be no such fracturing.So, which way do you want it to be? It was indeed soft when the layers attained their geometry. And it was, indeed, an effect of gravity.The problem is that you have not shown that this happened after the entire rock sequence was deposited. And you have not shown that it was a tectonic event by 'intruding' the gneiss into the sandstone (in fact, you have just now denied this). Why would there be such a discrepancy in the softness of the rocks?And that's not even the point. The point is that you have not shown how the evidence supports your scenario over anyone else's. That is, you have not provided evidence. No one has said that.

(Deleted due to off-topic nature.) Edited by edge, : No reason given.

And these are folded planes... Edited by edge, : No reason given.

By saying this:"It dropped into the lower place in the gneiss, it merely followed gravity, ... "ABE: This seems to be in clear opposition to your statement that the sediments were intruded and owed their shape to the intrusion of the Archean rocks.ABE: Besides, what do you mean by "lower places in the gneiss", if they were not there before the sandstone was deposited?Edited by edge, : No reason given.Edited by edge, : No reason given.

You have missed the point completely. I was showing you that planes need not be flat.ABE: If it was not your intent to deny that a deformed plane is not a plane, please explain. Edited by edge, : No reason given.

Then why did you write this? ABE: I interpreted this to mean that you think the lower sediments are/were softer than the ones higher in the roadcut. Is that what you meant?Edited by edge, : No reason given.

Only if you accept a weird interpretation of the Great Unconformity and various other unconformities and faulting events.ABE: For instance, we have faults that are truncated by the Great Unconformity. That means that there was a tectonic event before the GU. Please explain.ABE: We also have gross difference in metamorphic grade across the unconformity. Please explain.Yes, you provide evidence, but then you ignore huge tracts of other evidence against your position. Edited by edge, : No reason given.

I believe that is correct. That is one of my concerns in the interpretation of this roadcut. If we were there, it would be more obvious. Also, thought of that. Since we are across the highway, that should be minimized, but it's a real possibility that we are getting a distorted idea of the thickness. As I mentioned in one of my earlier posts, I don't really want to get into the geometry of the roadcut too much. I am, however, impressed by the continuity of the bedding plane I outlined in orange, vis a vis the possibility of deformation in the sequence.

Except that there is no evidence of shearing.ABE: With all of the evidence for irregular surfaces in the 'monadnocks', etc., how do you create shearing along the unconformity only a short distance away? It would be like sliding a sheet of plywood over another, when there are a few nails holding them together. Edited by edge, : No reason given.

To place unmetamorphosed sandstone against high-grade metamorphic gneisses with no overlap (no metamorphism in either the Tapeats or the GC Supergrou), you need a regional fault. Even the scale of the Grand Canyon wouldn't be enough, particularly considering that there is no evidence of shearing on the unconformity.

I think that I missed your evidence on this. Could you please repeat it for the record?You are saying that the gneiss and sandstone are a continuous sequence of sediments (?), and that the gneiss and sandstone were deformed at the same time, along with formation of the unconformity?

But none of these are evidence for your scenario. They are better explained by the mainstream view, especially considering other evidence which you seem to ignore (or in some cases, deny).

Well, there seem to be several viewpoints around here, but any one of them is better than yours for the reasons I have given. Well, that is part of the problem. You have a belief system, we have evidence, basic principles, experience and logic. And, perhaps, better eyesight. If you are saying that sediments cannot be deposited on a slope, you are wrong. It can and does happen, and it is very common. You have been given demonstrations and examples.And I'm not even saying that's what happened.I'm just saying that there is no evidence that the features we see are not related to sedimentation.

There are two others that I like. One is that they are deposited by water currents and we have a cross-bedded sand bar-type situation. Another is that there is a degree of compaction over the Precambrian high point. A third would be a combination of all of the above, including the direct deposition on a sloping surface.In all cases, these are what we call 'syndepositional'.They do not require shearing on the unconformity, nor some odd notion of 'intruding' blocks of gneiss. Actually, they are not necessarily laid down horizontallly. However, deformation can occur afterward.I'm not sure what your point is here. I have not 'proven' it to your satisfaction and never will. In fact, I do not intend to prove anything. I'm only saying that you do not have supporting evidence for your scenario, whereas we do have evidence that you are wrong.