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Author Topic:   Young earth explanations for Angular Unconformities
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 129 of 202 (796647)
01-02-2017 11:00 AM
Reply to: Message 112 by edge
01-01-2017 11:39 AM


Faith has countered with the idea that the weathering has occurred with the modern exposure of the outcropping and affected both sides of the unconformity. That doesn't quite work because then all outcroppings of the granite would show such weathering, not just where the unconformity occurs.
I gave a good reason for my argument, that the depression in the granite on the left side of the picture beneath the lowest sandstone layer, (also the smaller depression on the far right) should have filled with sand when that layer was deposited, if the erosion of the surface of the granite had been the result of long exposure at the surface before the deposition of the sand. Instead the sandstone layer is clearly a layer over it, and didn't fill up that depression. Therefore the depression in the granite had to have occurred after the sandstone layer was in place. I also pointed out that the underside of the sandstone is indented upward right over that depression in the granite, which suggests that whatever cut the granite also cut the sandstone, adding to this conclusion. In any case there is no sandstone filling that depression, and you need to explain that on your theory.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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 Message 112 by edge, posted 01-01-2017 11:39 AM edge has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 130 of 202 (796650)
01-02-2017 11:27 AM
Reply to: Message 126 by Percy
01-02-2017 8:12 AM


Just to respond to one confusing point: You say I supposedly think that flat layers could tilt into a diagonal formation as you illustrate, going on to say
Of course, this is impossible, for one thing because it requires cubic milies of material to simply disappear. This diagram attempts to illustrate some of the missing material after rotation. All the material represented by the diagonal lines and up through the upper left has simply disappeared
A complete misrepresentation of what I've been saying.
First, the strata below the unconformity happen to be straight upright at Siccar Point, not tilted as you've illustrated, and second although I may not have said it every time I described it I did correct it to say what I mean is that this section is the result of BUCKLING -- or folding -- of the strata. So what would have been sheared off is the rounded upper part of the buckling, and not a whole length of strata, as shown in an image by Lyell of the same formation near Siccar Point:
I can't figure out how to copy and paste the image alone so here's a page of my blog where I posted it some time ago. It's the third image down.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 126 by Percy, posted 01-02-2017 8:12 AM Percy has replied

Replies to this message:
 Message 132 by Percy, posted 01-02-2017 2:47 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 131 of 202 (796651)
01-02-2017 11:43 AM
Reply to: Message 111 by edge
01-01-2017 11:24 AM


Is that image of the area of Siccar Point? I thought it was supposed to be another shot of the granite-sandstone unconformity.
Anyway, you are using the irregular surface of the tilted strata as an argument against my shearing idea, but don't you have an even bigger problem explaining how flat layers of sandstone got laid out on top of such a surface? And what is that layer of "basal conglomerate?" I guess you interpret it as the erosion that occurred on the surface of the lower section during long exposure? I'd suggest it's likely to be the eroded material caused by the shearing I'm talking about.
Also I don't see why the shearing always has to create a perfectly flat surface. If there's enough resistance it could be pretty lumpy.
That whole formation obviously tilted after it was laid down, same as at Siccar Point, since the upper section would have originally been horizontal. Whatever caused that tilting could have affected the surface of the lower section.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 111 by edge, posted 01-01-2017 11:24 AM edge has replied

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 Message 136 by edge, posted 01-02-2017 9:53 PM Faith has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 135 of 202 (796669)
01-02-2017 7:40 PM
Reply to: Message 132 by Percy
01-02-2017 2:47 PM


Thank you for posting such a good image of Lyell's drawing.
I was referring to the pictures of Siccar Point (in the video on this thread, but also in some of edge's posts), that show the lower section to be upright, at least far more upright than the low-slung illustrations you were falsely attributing to me. The drawing by Lyell is of a different part of the area, not THE Siccar Point itself, and the point of posting it is to show that the strata were folded rather than extended as you claimed, so that it was the folded part that was broken off. (However, at those locations where the strata are more slightly tilted they would still break off, leaving sections of strata, along with rubble. But that low degree of tilt isn't the case at Siccar Point).
... but at any rate the degree of tilt doesn't matter. What you're missing is that tilting or bending or buckling of underlying layers without affecting the layers above isn't possible..
I've many times made the case that it is quite possible, on thread after thread as a matter of fact, and what makes it possible is the great weight of the strata that would have been above it at the time it occurred, giving enormous resistance to the tectonic pressure so that it dissipates at the point where the two forces are about equal, aided in most cases by the fact that the unconformity usually occurs between two different kinds of rock, the different textures providing a point of least resistance and facilitating slippage between them.
Besides. you've shown too many times that our sense of the physical world is shall we say untrustworthy to put it politely.
You go on to say it isn't possible
.. because it requires cubic miles of material to simply disappear into thin air.
Perfect example of your inability to picture physical reality. The whole upper stack would be lifted by the tectonic action beneath it. Some of the eroded material may accumulate at the unconformity where the strata are broken or sheared off, but in any case the whole block is broken and displaced and stays beneath the unconformity, which may stretch for miles.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 132 by Percy, posted 01-02-2017 2:47 PM Percy has replied

Replies to this message:
 Message 142 by Percy, posted 01-03-2017 9:04 AM Faith has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 140 of 202 (796678)
01-03-2017 1:50 AM
Reply to: Message 139 by edge
01-02-2017 10:39 PM


You keep claiming that this or that phenomenon WOULD HAVE been present if my theory is correct. But clearly the rock WAS folded, which can be seen on Lyell's drawing, and you say they don't show those phenomena. How can you explain that? Also how can you explain the folding at all without tectonic pressure? I asked that a post or two ago, did I miss your answser? AND assuming that the folding occurred before the strata above were laid down, how on earth could that happen at all, one, meaning I'd think it would be hard to explain how it could occur without a counterweight above it. and two, assuming somehow it did fold without anything above it, where did the material go that presumably disappeared by the time the strata came along? Is there evidence that it trickled down into the folds somehow? Doesn't seem to be the case, especially that much material that supposedly I have a problem accounting for. Seems to me you have at least as much of a problem explaining your senario as you think I have.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 139 by edge, posted 01-02-2017 10:39 PM edge has not replied

Replies to this message:
 Message 141 by PaulK, posted 01-03-2017 2:07 AM Faith has not replied
 Message 143 by Percy, posted 01-03-2017 9:17 AM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 144 of 202 (796695)
01-03-2017 10:41 AM
Reply to: Message 143 by Percy
01-03-2017 9:17 AM


You keep claiming that this or that phenomenon WOULD HAVE been present if my theory is correct. But clearly the rock WAS folded, which can be seen on Lyell's drawing, and you say they don't show those phenomena.
This isn't the point that's being made. No one thinks the layers weren't folded by geologic forces.
Then why bother talking about supposed evidence for folding that in fact is not present although you know folding occurred? And what is a "geologic force" pray tell? Why not say "tectonic" or is there some other kind of "geologic force" that explains this.
The point is that when the layers were folded the current overlying layers were not present. There were other layers atop the folded layers that were folded along with them and then were later eroded away.
Wowsy wow. Now there's an entirely new theory I've never heard before. Never ever has such an idea entered into these discussions of the formation of angular unconformities. And if this is the point, again I ask why bring up evidence of folding when there is no such evidence present in the current examples? Eh? This discussion has gone from confused to bizarre.
There were layers present when it folded? And they got folded with them and then were so completely eroded away there isn't a trace of them to be found? Unfortunately you've removed all the words I might reasonably use to describe this sort of ridiculousness.
AND assuming that the folding occurred before the strata above were laid down, how on earth could that happen at all, one, meaning I'd think it would be hard to explain how it could occur without a counterweight above it.
Why do you think tectonic forces generated from within the Earth require some sort of counterweight?
Golly gosharoony, I was making the intelligent rational point that folding isn't too likely to occur without some resistance above it. More than a layer or two I'd venture. And I note that you don't have an explanation. Perhaps you should leave such questions to edge.
and two, assuming somehow it did fold without anything above it, where did the material go that presumably disappeared by the time the strata came along?
It was eroded and carried away to the lowest geologic point (often the ocean) by wind, rain, streams and rivers. It's the same process we see happening all around the world today. The present is the key to the past.
The thing is, we've got these folded slabs of rock that cover who knows how much geography when first formed, and somehow their tops were cut off, presumably by erosion before strata were laid over them. Thing is, they would form a surface riddled by cracks, not a surface conducive to, say, water runoff, and yet the cracks wouldn't be large enough to hold much eroded material. Seems to me it would pile up. Ya know, on ordinary physical principles, given the actual surface that would have been formed by folded sheets of wannabe rock.
It's amazing that after all your time here you still don't know the basics of geology. To disagree with them is one thing, but to not even know them despite years of discussion is unfathomable.
What we have here is wild empty name-calling. This discussion at this point has absolutely nothing to do with the basics of geology. This idea you've been describing has never before entered into the discussion of angular unconformities. I strongly recommend that you stay out of it to avoid contributing further to the utter nonsense. Edge is capable of confusing things enough without your help.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 143 by Percy, posted 01-03-2017 9:17 AM Percy has replied

Replies to this message:
 Message 148 by Percy, posted 01-03-2017 12:15 PM Faith has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 145 of 202 (796697)
01-03-2017 10:50 AM


...
Edited by Faith, : No reason given.

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 150 of 202 (796711)
01-03-2017 2:13 PM
Reply to: Message 147 by edge
01-03-2017 11:34 AM


I don't see how most of what you and Percy are talking about is relevant to the points I've been trying to make. I suppose I could speculate about the picture you posted, though I think I'd need more information such as where it is located, and the supposed age or time period of the folded rocks, but since I don't see its relevance to the discussion I don't see putting in the effort. The angular unconformities appear to have been formed as I've described. They are a different thing. And this idea that there were strata above them that eroded away before more strata were deposited, is, as I said, a brand-new idea never before applied in the discussion of these things. Which introduces some of the flavor of a flim-flam even though its purposes isn't at all clear.
Upshot: I don't see any point in continuing this discussion. You and Percy might as well go on with your irrelevant musings.

This message is a reply to:
 Message 147 by edge, posted 01-03-2017 11:34 AM edge has not replied

Replies to this message:
 Message 151 by Percy, posted 01-03-2017 2:55 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 155 of 202 (796729)
01-03-2017 7:22 PM
Reply to: Message 152 by edge
01-03-2017 6:32 PM


What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?
The uppermost portion of the tilted strata. Not a separate layering of strata.
Duh.
ABE: This post was not meant for edge but for Percy, so I have rewritten it to the right person in Message 163
Edited by Faith, : 63]

This message is a reply to:
 Message 152 by edge, posted 01-03-2017 6:32 PM edge has replied

Replies to this message:
 Message 159 by edge, posted 01-03-2017 7:35 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 156 of 202 (796730)
01-03-2017 7:25 PM
Reply to: Message 138 by edge
01-02-2017 10:33 PM


No such thing is present at Siccar or any other place we have discussed. They are ubiquitous in any area that has been tectonized (which would include Faith's scenario for unconformities).
I still want to know how you explain the FACT that the rocks ARE folded despite the absence of this sort of evidence of folding you are talking about.
I also don't think you've answered the question about how rocks get folded or tilted without tectonic pressure.

This message is a reply to:
 Message 138 by edge, posted 01-02-2017 10:33 PM edge has replied

Replies to this message:
 Message 157 by edge, posted 01-03-2017 7:32 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 158 of 202 (796732)
01-03-2017 7:34 PM
Reply to: Message 147 by edge
01-03-2017 11:34 AM


For rocks to fold I'd still guess there has to be some kind of resistance to the force that is folding them. It doesn't have to be overhead, but in this picture you've posted that is still a big possibility. What are the ages of those rocks in that picture? If they are, say, low in the Paleozoic, then there would have been a deep stack of layers above them just as at Siccar Point. But I'd also surmise the possibility of some resistance between the upper folded block and the flat layers beneath it, giving sliding movement punctuated by jerky stops, based on the fact that the folds are not nice and smooth as they are at Siccar Point, but irregular, suggesting jerky movement.

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 Message 147 by edge, posted 01-03-2017 11:34 AM edge has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 160 of 202 (796734)
01-03-2017 7:37 PM
Reply to: Message 157 by edge
01-03-2017 7:32 PM


I haven't "seen" any of your claims so far. It's all a big cheat. As always, there comes a point when discussions with you devolve into you making unverifiable claims in order to win the argument. This gets old.

This message is a reply to:
 Message 157 by edge, posted 01-03-2017 7:32 PM edge has replied

Replies to this message:
 Message 166 by edge, posted 01-03-2017 7:59 PM Faith has replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 161 of 202 (796735)
01-03-2017 7:38 PM
Reply to: Message 159 by edge
01-03-2017 7:35 PM


I was talking to Percy, not you. I meant to be anyway, since what I quoted is his constant refrain. Now I see it was from you. Sorry.
He's the one making the dogmatic claim that there were horizontal strata that eroded away, which is the idea I'm saying has never entered into this discussion before.
This is what he said in Message 151 that I thought I was answering:
What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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 Message 159 by edge, posted 01-03-2017 7:35 PM edge has not replied

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 Message 165 by Percy, posted 01-03-2017 7:59 PM Faith has not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 163 of 202 (796737)
01-03-2017 7:46 PM
Reply to: Message 151 by Percy
01-03-2017 2:55 PM


Percy writes:
What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers?
The uppermost portion of the tilted strata. Not a separate layering of strata.
Duh.

This message is a reply to:
 Message 151 by Percy, posted 01-03-2017 2:55 PM Percy has seen this message but not replied

  
Faith 
Suspended Member (Idle past 1444 days)
Posts: 35298
From: Nevada, USA
Joined: 10-06-2001


Message 167 of 202 (796742)
01-03-2017 8:01 PM
Reply to: Message 164 by edge
01-03-2017 7:55 PM


It had to go somewhere on either theory, and as I said before if it was all eroded away at the surface there would be some evidence of it in the folds of the rocks, but apparently there isn't. On my scenario I suggest it was pushed out at the "front" of the formation, the front being the part exposed to view in all the pictures. There's usually lots of rubble around formations. Or it got pushed along the horizontal path of the unconformity. Somewhere there is an unidentified pile of rubble that is where it went.

This message is a reply to:
 Message 164 by edge, posted 01-03-2017 7:55 PM edge has replied

Replies to this message:
 Message 171 by edge, posted 01-03-2017 8:20 PM Faith has not replied
 Message 172 by Percy, posted 01-03-2017 8:33 PM Faith has not replied

  
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