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

Your picture doesn't look anything like the Siccar Point picture, what is it you want me to see there?

Yes, that's what it looks like to me. But other evidence is the straightness of the upper strata too, showing no signs of having had to conform to irregularities in the lower section, as I already mentioned.

I started out this discussion with some pictures noting what look to me to be amazingly level (horizontal) straight (flat but nothing's perfect) contact lines at various locations of the Great Unconformity. (except the third picture does seem to be a rogue that got in there by mistake: I think it is an unconformity, however, but from some place in South America).So I start with that impression from those pictures in Message 213 and Message 313. Some dispute that they are as straight and level as I claim but the lines are there to show it so the objections make no sense.Anyway, the challenge was to show that erosion alone could produce such remarkably level and flat surfaces on top of distorted strata or lumpy hard rocks like schist. Many NEAR- level surfaces were shown, but none as level and flat as those in my pictures IMHO. Nobody's succeeded at that, and Dr. A's doesn't either, IMHO.I wouldn't say that layers NEVER deposit unevenly, I'm only saying that's not the case in my pictures, and the ones of very uneven examples of the G.U. had to have been disturbed after deposition IMHO, could not have been deposited that way.I hope this is clearer.

I thought that's what Percy wanted me to indicate: to explain the unevenness of the lower section as the result of erosion after the deposition of the above section. I'm sure you are still free to offer a different interpretation. The only debris I see is in what I called the eroded zone above the lower section, which I outlined in blue; is that what you are referring to? In the lower section I yellow-lined evidence of recent erosion since exposure. But I HAVE answered this. They ARE tremendously weathered, judging by their being mere splinters, mere "shadows of their former selves" as I put it. The upright strata below offer exposed upper ends to the weather, explaining their unevenness, and unevenness seen at many levels too, as I marked in yellow; but straight flat strata would remain straight, just be reduced to such skeletal remains as seen. This is how I've interpreted the difference more than once already. The amazing thing is that there are so many examples of remarkable levelness and straightness of the G.U. There must be others, with monadnocks for instance, where they were originally irregular, and YET EVEN THERE THE OVERALL IMPRESSION IS OF A REMARKABLE LEVELNESS AND STRAIGHTNESS MERELY INTERRUPTED HERE AND THERE BY SUCH IRREGULARITIES. I don't see anything I've said or shown on the picture that contradicts that description. The surface of the unconformity is now shown only in the uneven upper broken ends of the strata of the lower section.

OK, noted. But that doesn't change the fact that none of the pictures show a surface as level and straight as those of the G.U. in the pictures I posted.So I still say what I said above: erosion alone [has not been shown to] produce such remarkably level and flat surfaces on top of distorted strata or lumpy hard rocks like schist.ABE: Afterthought: Erosion deposited ON TOP of the land surface is now the argument? But what we see in the G.U. is the level surface of the rock that's there: the schist in some cases, the tilted strata in others. Where's this band of erosion? Edited by Faith, : No reason given.

Reading out of context of course.

I quoted amply for him to get the context.

.Edited by Faith, : No reason given.

BECAUSE IT IS HORIZONTAL. As I said already.

Because the surface of the unconformity is vertical strata and that upper surface is horizontal. The vertical ends of the strata would be more vulnerable to severe weather, being easily broken when thinned down. That's why there are so many stumps of the upright lower strata. The upper strata are severely weathered nevertheless as I noted, but being horizontal the weather batters against it but doesn't break it as easily. There must be a simple principle of physics that explains this:The horizontal gives less resistance to the weather than the vertical?The vertical has more exposed surfaces?Would you be more or less stable standing up or lying down in a gale?No it isn't horizontal any more, it's on a slant, but it still presents more of a flat surface to the weather than the upright strata do.Would a picket fence do better in a gale or a flat deck?Is there a reason airplanes have horizontal flat wings or would they do OK if they were vertical?Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

Abrasion between upper and lower sections as already explained somewhere back there.ABE: Message 416 about 2/3 of the way down.ABE: And here I should add that I'm not answering parts of your posts because I don't get what you are saying.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

But they ARE exposed, as Percy just got me to clarify.But hey, so much for civil discourse.

That Death Valley picture isn't evidence of much of anything, let alone cross bedding on the unconformity. It's undecipherable.

I'm glad Percy is monitoring this thread but communication is nevertheless still difficult.I just want to try to explain how I think abrasion could have occurred between upper and lower sections of an angular unconformity. I've speculated that the "detachment" needed is the fact that, at least in the Great Unconformity of the Grand Canyon and the one at Siccar Point, the upper (horizontal) and lower (folded or tilted) sections are different kinds of rock. At the G.U. it's Tapeats sandstone above either schist or a block of strata of different kinds of rock, and at Siccar point it's red sandstone above grey sandstone / "greywacke." I speculate that there is enough textural difference between the two sections for there to be some potential for disengagement between them under lateral tectonic pressure on the lower section. That plus a point in the stack where the weight of the stack above gives resistance equal to the tectonic force from below. A combination of these two factors would pinpoint the contact between two layers that would have the most "slippage," allowing the lower to buckle and slide under the upper. [ABE: KEEP IN MIND that I'm assuming that there was a very deep stack of strata above the current horizontal section, at Siccar Point just as there is in the GC, as well as the whole formation's extending horizontally across the whole land area. /ABE]My answer is No to Percy, exposure is not required. And to edge: No, in my scenario I believe it happened under the tectonic force that occurred as the Flood water was receding -- about 4300 years ago. ( In my scenario erosion would have occurred at the time of the movement between the layers, but in these recent discussions of Siccar Point I'm talking about "modern" erosion that has occurred since its formation, through the intense weather on the coast of Scotland. I think I've answered this in my explanation above.Here are some of my Blog posts on Siccar Point. I do explain the idea of how the two sections of an angular unconformity could already have existed when the lower was tectonically folded. These are old posts and I haven't updated them but I'd change a few things since recent discussions here. Nothing, however, that affects the idea of how the lower section could have been moved while the upper remained intact.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.Edited by Faith, : No reason given.

I think this is implicit in my discussions, but if not, more clarification might help. Perhaps my latest post, Message 494, will clarify some things.Edited by Faith, : No reason given.Edited by Faith, : No reason given.