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Author Topic:   Young earth explanations for Angular Unconformities
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 106 of 202 (796591)
12-31-2016 9:28 PM
Reply to: Message 102 by Faith
12-31-2016 4:23 PM


Re: Siccar Point angular unconformity video
Then why are the breccias found in beds at all,...
Cuz of the layering that would have contained them I would suppose
But it is a layer concordant with the overlying beds.
And it consists of a matrix identical to the sandstone, but not fragments of the red sandstone. In other words, they are actually a part of the red sand deposition.
Furthermore, there are layers and channels of older rocks cobbles within the red sand sequence.
Why are there not fragments of the upper beds found within the lower?
Because it was the lower strata that folded and got broken as a result of being forced upward and along the lower surface of the upper. The upper didn't break, but were rather lifted by the folding lower layers which would have scraped the sediment of the bottommost layer at the unconformity.
The problem here is that the unconformity is not planar. It is highly irregular due to variable resistance to erosion of different layers in the older sequence.
I have seen plenty of sheared surfaces, some of them parallel to bedding and they are not so irregular. Irregularities of the type visible at Siccar Point forbid the possibility of shear.
I should say the lower were folded rather than tilted, but their upper surfaces would have broken off in that case too. Some pictures from that same area some distance from Siccar Point itself do show a bending of the lower layers where you can still see the fold itself, ....
Actually, I'm not talking about the large-scale folds. I'm discussing the drag folds along your shear plane.
They don't exist. If you hole a deck of cards vertically and then drag the top edge, you form drag folds in the cards that tell you the direction of movement. There are no such drag folds in the older sequence.
... but in any case there's no need to assume a very high degree of ductility, and also, the tectonic pressure should have had the effect of hardening the rock at the same time it folded it.
It doesn't have to be high. But if the rocks are folded in a semi-ductile state (as you profess), one would think that drag folds would be prominent.
Here is an example of drag folding:
The observable evidence at Siccar Point is that there is no visible difference between the degree of weathering of upper and lower sections.
You are simply repeating an irrelevant point.
As I tried to say, the very time the sand was being deposited was just after the underlying rocks were exposed by erosion. There is virtually no difference in this case. That is because the action was all occurring at the shoreline where erosion and deposition both occur.
Which to my mind is evidence for a young earth there as well as at Siccar Point, because in the enormous time spans described by standard theory the lower section of Siccar and Mt. Rushmore too, shouldn't be holding up well at all.
Well, that's the point. Those rocks, while being highly resistant to erosion are also the most recently exposed.
You are creating a straw-man argument.
Creationists have shown that what you call evidence of weathering is chemically different from what you get with weathering.
I'll need a reference on that.
Abraded sediment perhaps but not weathered rock. And I'm sorry but I don't see the relevance of paleosols.
I'm guessing that my explanation above covers this. The process does not include long times between erosion of the lower sequence and deposition of the upper rocks in the case of Siccar Point.

This message is a reply to:
 Message 102 by Faith, posted 12-31-2016 4:23 PM Faith has replied

Replies to this message:
 Message 109 by Faith, posted 12-31-2016 11:31 PM edge has not replied
 Message 113 by Faith, posted 01-01-2017 11:52 AM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 107 of 202 (796592)
12-31-2016 9:57 PM


Just for general information, here is an image of the Great Unconformity where there is evidence of weathering in granite below the erosional surface.
Note the weathering rinds that formed along fractures in the Pikes Peak Granite, ostensibly before the overlying Cambrian sandstone was deposited.
This weathering occurred because the granite was exposed for a long time prior to deposition of the Sawatch sandstone was deposited. This is different from the case at Siccar Point where erosion occurred right up to the point where deposition of the sand started.

Replies to this message:
 Message 108 by Faith, posted 12-31-2016 11:01 PM edge has replied
 Message 110 by Percy, posted 01-01-2017 7:22 AM edge has replied

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


Message 108 of 202 (796593)
12-31-2016 11:01 PM
Reply to: Message 107 by edge
12-31-2016 9:57 PM


Note the weathering rinds that formed along fractures in the Pikes Peak Granite, ostensibly before the overlying Cambrian sandstone was deposited.
I'm glad you said "ostensibly" because erosion on an exposed surface isn't the only possible explanation. I'd point out for starters how the channels in the granite are capped by similarly eroded sandstone, on their undersides in this case. If the granite had eroded before the sand was deposited, first the sand would have filled in the depressions, and second, the underside of the sandstone shouldn't be eroded at that same location. Most erosion between strata can be explained as occurring there after they were all in place, from water runoff between layers at the contacts. That must have happened here too, even cutting into the granite. Whatever cut the granite also cut the sandstone, and at the same time, showing both were already there at the time.
Also the granite is surprisingly flat --abe: though tilted? --at the unconformity despite the lumps and depressions. I know you all claim that surface erosion creates flatness. It's never been demonstrated though it's been illustrated from imagination. Abrasion could do it I'd guess. Or maybe it's even possible that the magma welled up after the strata were in place, melting other rocks until it got to this level. Guessing of course, but it's a guess based on the observations above that suggest erosion after deposition of all layers.
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.

This message is a reply to:
 Message 107 by edge, posted 12-31-2016 9:57 PM edge has replied

Replies to this message:
 Message 111 by edge, posted 01-01-2017 11:24 AM Faith has replied

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


Message 109 of 202 (796594)
12-31-2016 11:31 PM
Reply to: Message 106 by edge
12-31-2016 9:28 PM


Re: Siccar Point angular unconformity video
Then why are the breccias found in beds at all,...
Cuz of the layering that would have contained them I would suppose
But it is a layer concordant with the overlying beds.
Of course. The clasts would have been broken off the underlying layers during the movement between the sections caused by the tectonic pressure. The lower upright layers would have slid along underneath the upper horizontal layers, and the broken pieces would have become embedded in those layers, along their horizontal length. This was certainly how the giant boulder of why-can't-I-renenber-its-name,* that translucent hard rock that was one of the layers of the uptilted Supergroup strata beneath the Grand Canyon, the boulder that broke off and got embedded in the Tapeats sandstone above the Great Unconformity, as a result of the tectdonic movement that tilted the Supergroup, according to my creationist explanation, of the movement between the upper and lower sections, a movement that slid something like a quarter of a mile, since that is the distance of the boulder from its source layer. Same process as at Siccar Point, pieces of the lower strata getting embedded in the upper horizontal sand layers.
I'll have to come back to this.
===================================
* Quartzite!
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.

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 Message 106 by edge, posted 12-31-2016 9:28 PM edge has not replied

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.2


Message 110 of 202 (796599)
01-01-2017 7:22 AM
Reply to: Message 107 by edge
12-31-2016 9:57 PM


I wasn't sure where to look in the photo, so consequently I didn't understand this:
edge writes:
This weathering occurred because the granite was exposed for a long time prior to deposition of the Sawatch sandstone was deposited. This is different from the case at Siccar Point where erosion occurred right up to the point where deposition of the sand started.
--Percy

This message is a reply to:
 Message 107 by edge, posted 12-31-2016 9:57 PM edge has replied

Replies to this message:
 Message 112 by edge, posted 01-01-2017 11:39 AM Percy has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 111 of 202 (796605)
01-01-2017 11:24 AM
Reply to: Message 108 by Faith
12-31-2016 11:01 PM


I'm glad you said "ostensibly" because erosion on an exposed surface isn't the only possible explanation. I'd point out for starters how the channels in the granite are capped by similarly eroded sandstone, on their undersides in this case.
Problem is that we see the same granite exposed at the surface elsewhere, without the unconformity present, that do not show such weathering.
If the granite had eroded before the sand was deposited, first the sand would have filled in the depressions, ...
Which, in fact, happens.
Note the irregularities in the unconformity surface in the above image. In detail, the irregularities become even more obvious.
... and second, the underside of the sandstone shouldn't be eroded at that same location. Most erosion between strata can be explained as occurring there after they were all in place, from water runoff between layers at the contacts. That must have happened here too, even cutting into the granite. Whatever cut the granite also cut the sandstone, and at the same time, showing both were already there at the time.
Well, we do have some fractures that cut both the granite and the sandstone but those fractures don't have as severe weathering as the older ones showing spheroidal weathering.
Also the granite is surprisingly flat at the unconformity despite the lumps and depressions. I know you all claim that surface erosion creates flatness. It's never been demonstrated though it's been illustrated from imagination. Abrasion could do it I'd guess. Or maybe it's even possible that the magma welled up after the strata were in place, melting other rocks until it got to this level. Guessing of course, but it's a guess based on the observations above that suggest erosion after deposition of all layers.
The Siccar Point rocks clearly show irregularities that would not be present on a sheared surface.
However, if you want to get technical, the Neoproterozoic was a time of global glaciation and there are many locations where glacial erosion formed nearly flat surfaces. I have shown you some recent glaciated surfaces on the Baltic Shield that look nearly identical to some of the flat surfaces you refer to.
Basically, your problem is that you have no tectonic fabrics to present and you do not explain the geometry of most unconformity surfaces.

This message is a reply to:
 Message 108 by Faith, posted 12-31-2016 11:01 PM Faith has replied

Replies to this message:
 Message 131 by Faith, posted 01-02-2017 11:43 AM edge has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 112 of 202 (796606)
01-01-2017 11:39 AM
Reply to: Message 110 by Percy
01-01-2017 7:22 AM


I wasn't sure where to look in the photo, so consequently I didn't understand this:
The issue was an apparent lack of weathering below the unconformity at Siccar Point. Faith thinks that because the rocks are not so weathered that they were never exposed at the surface. This is support her idea that the unconformity is actually some kind of a shear zone.
My point is that, because erosion was strongly mechanical (wave action) the more weathered rock was being constantly removed right up to the point of deposition of the Red Sand. Consequently, there is little evidence of a long period of erosion.
To emphasize this point, I tried to find a location where erosion was not so mechanical and weathered rock might not be removed by the time the overlying sediments were deposited on the unconformity. The image I showed was of the Pikes Peak Granite just below the Great Unconformity. It shows deep spheroidal weathering (creating rounded boulders) due to long exposure at the surface of the earth. If that granite were not exposed to weathering, this feature would not be present.
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.
Sorry that I was not more clear in my reasoning. Let me know if you want more explanation.
Edited by edge, : No reason given.
Edited by edge, : No reason given.

This message is a reply to:
 Message 110 by Percy, posted 01-01-2017 7:22 AM Percy has replied

Replies to this message:
 Message 126 by Percy, posted 01-02-2017 8:12 AM edge has replied
 Message 128 by Faith, posted 01-02-2017 10:50 AM edge has not replied
 Message 129 by Faith, posted 01-02-2017 11:00 AM edge has not replied

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


Message 113 of 202 (796607)
01-01-2017 11:52 AM
Reply to: Message 106 by edge
12-31-2016 9:28 PM


Re: Siccar Point angular unconformity video
And it consists of a matrix identical to the sandstone, but not fragments of the red sandstone. In other words, they are actually a part of the red sand deposition.
Not getting this. Isn't the matrix the red sandstone itself? The rock pieces are the greywacke sandstone of the lower section embedded in the red sandstone.
Furthermore, there are layers and channels of older rocks cobbles within the red sand sequence.
You'd have to show me this, I don't get your point.
Why are there not fragments of the upper beds found within the lower?
Because it was the lower strata that folded and got broken as a result of being forced upward and along the lower surface of the upper. The upper didn't break, but were rather lifted by the folding lower layers which would have scraped the sediment of the bottommost layer at the unconformity.
The problem here is that the unconformity is not planar. It is highly irregular due to variable resistance to erosion of different layers in the older sequence.
In other words it is so eroded it's hard to tell what its original form was; it might even have been planar but after thousands of years of battering by wind and sea water from all sides and even through the upper section as these erosive processes broke it down, it's become irregular and the upper section has sort of settled into it in an irregular way. But it could have broken off irregularly and its pieces been embedded in the upper section in the same way anyway.
I have seen plenty of sheared surfaces, some of them parallel to bedding and they are not so irregular. Irregularities of the type visible at Siccar Point forbid the possibility of shear.
That's rather a pedantic point. It's possible for the action I'm describing to have occurred as described and left a more irregular contact. Pieces would still have broken off and been embedded in the upper section which settled into the lower. Besides, if the upper had been deposited long after the lower was eroded, shouldn't we see the red sandstone filling all the spaces in the lower instead of sitting on it as a horizontal formation?
I should say the lower were folded rather than tilted, but their upper surfaces would have broken off in that case too. Some pictures from that same area some distance from Siccar Point itself do show a bending of the lower layers where you can still see the fold itself, ....
Actually, I'm not talking about the large-scale folds. I'm discussing the drag folds along your shear plane.
They don't exist. If you hole a deck of cards vertically and then drag the top edge, you form drag folds in the cards that tell you the direction of movement. There are no such drag folds in the older sequence.
I don't get your card analogy, but there had to be quite a bit of material from the lower section that was either sheared or broken away, so I'm not sure drag folds would be left from all that.
... but in any case there's no need to assume a very high degree of ductility, and also, the tectonic pressure should have had the effect of hardening the rock at the same time it folded it.
It doesn't have to be high. But if the rocks are folded in a semi-ductile state (as you profess), one would think that drag folds would be prominent.
Even if the shearing process took off quite a depth of material? Even after thousands of years of erosion? If you say so, I'll chalk that one up on your side of the argument for now.
Here is an example of drag folding:
I can barely make it out but I think I get the gist.
The observable evidence at Siccar Point is that there is no visible difference between the degree of weathering of upper and lower sections.
You are simply repeating an irrelevant point.
Rather relevant I'd say.
As I tried to say, the very time the sand was being deposited was just after the underlying rocks were exposed by erosion. There is virtually no difference in this case. That is because the action was all occurring at the shoreline where erosion and deposition both occur.
That imaginary sort of "shoreline" that geologists are always finding by small clues I suppose? Possibly a water line formed during the receding Flood. In which case there wouldn't be a clear difference, as you are saying, just as there wouldn't if it was caused by the Flood, which of course it was. But doesn't that fly in the face of the standard theory that assigns millions of years to layers of rock? How would it happen that these particular sections aren't to be assigned such hugely different ages?
Which to my mind is evidence for a young earth there as well as at Siccar Point, because in the enormous time spans described by standard theory the lower section of Siccar and Mt. Rushmore too, shouldn't be holding up well at all.
Well, that's the point. Those rocks, while being highly resistant to erosion are also the most recently exposed.
Uh huh, how pat, how convenient. It's got all the earmarks of Flood formation but those earmarks can be rationalized somehow to fit the enormous age spans of standard theory -- by simply defining these rocks as deposited closely in time, eliminating all the other layers that would have had at some point to have been part of the formation. Where did those ancient layers go by the way?
Also, what makes the lower rocks "highly resistant?" In the film the Hutton party calls them "schistus" but they aren't schist, they are greywacke, which is a sandstone mixed with a small proportion of clay, making them somewhat harder or more resistant than the upper red sandstone but not as resistant as schist would be. And really, by standard theory they WOULD have been deposited much earlier than the upper. The Hutton group pictures them under water, not at a shoreline, and the upper sand being deposited much later. That would fit the usual scenario of the standard theory.
You are creating a straw-man argument.
Really?
Creationists have shown that what you call evidence of weathering is chemically different from what you get with weathering.
I'll need a reference on that.
As I recall it was in the video of the lecture on the Grand Canyon by Paul Garner of the British creationist society. I'll ahve to track it down. Sigh.
Abraded sediment perhaps but not weathered rock. And I'm sorry but I don't see the relevance of paleosols.
I'm guessing that my explanation above covers this. The process does not include long times between erosion of the lower sequence and deposition of the upper rocks in the case of Siccar Point.
That Likely Story again.

This message is a reply to:
 Message 106 by edge, posted 12-31-2016 9:28 PM edge has replied

Replies to this message:
 Message 114 by edge, posted 01-01-2017 12:14 PM Faith has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 114 of 202 (796609)
01-01-2017 12:14 PM
Reply to: Message 113 by Faith
01-01-2017 11:52 AM


Re: Siccar Point angular unconformity video
That's rather a pedantic point. It's possible for the action I'm describing to have occurred as described and left a more irregular contact. Pieces would still have broken off and been embedded in the upper section which settled into the lower. Besides, if the upper had been deposited long after the lower was eroded, shouldn't we see the red sandstone filling all the spaces in the lower instead of sitting on it as a horizontal formation?
That is what we see. Here is a detailed drawing.
Fig.1. The angular unconformity at Siccar Point, one of the key outcrops for Hutton to demonstrate the validity of his theory. This illustration was made by Sir James Hull in 1788, during an excursion lead by Hutton.
Explain the deposition of layered sediments in the crevices cut in the lower section.
Then tell me which way the upper block moved relative to the lower block.
Here is another image showing similar relationship.
And, in even more detail:

This message is a reply to:
 Message 113 by Faith, posted 01-01-2017 11:52 AM Faith has replied

Replies to this message:
 Message 115 by Faith, posted 01-01-2017 1:03 PM edge has not replied
 Message 116 by Faith, posted 01-01-2017 1:23 PM edge has replied

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


Message 115 of 202 (796612)
01-01-2017 1:03 PM
Reply to: Message 114 by edge
01-01-2017 12:14 PM


Re: Siccar Point angular unconformity video
OK, you've shown that there's red sandstone in the crevices. Now I have a different take on it. It would have been the scraping of the lower section, irregular as it is now, against the underside of the upper section, that caused the sand to fill those spaces. For one thing it looks like it came off a horizontal layer that was already there, rather than being deposited as loose sediment into the crevices originally, which would de-emphasize the layered effect, which it didn't
Edited by Faith, : No reason given.

This message is a reply to:
 Message 114 by edge, posted 01-01-2017 12:14 PM edge has not replied

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


Message 116 of 202 (796614)
01-01-2017 1:23 PM
Reply to: Message 114 by edge
01-01-2017 12:14 PM


Re: Siccar Point angular unconformity video
Another point: if you want to argue that the layering in the crevices proves deposition occurred after the lower irregular section had been there for a while, I'd point out that some time ago, a couple years by now maybe, HBD proved that sand depositing on an irregular surface would drape over the protuberances and not settle in the crevices in layers as I had supposed.
However, the layers don't fit my scenario either since they would have been disturbed by the scraping of the "picket" shapes illustrated in your drawing.
That suggests that neither explanation works.
However, the drawing is just a drawing, and nothing in the photos corroborates its presentation of layers in the crevices anyway.

This message is a reply to:
 Message 114 by edge, posted 01-01-2017 12:14 PM edge has replied

Replies to this message:
 Message 117 by edge, posted 01-01-2017 1:48 PM Faith has replied

  
edge
Member (Idle past 1706 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


Message 117 of 202 (796615)
01-01-2017 1:48 PM
Reply to: Message 116 by Faith
01-01-2017 1:23 PM


Re: Siccar Point angular unconformity video
Another point: if you want to argue that the layering in the crevices proves deposition occurred after the lower irregular section had been there for a while, ...
I'm not, I'm just saying that things are not as you described them.
... I'd point out that some time ago, a couple years by now maybe, HBD proved that sand depositing on an irregular surface would drape over the protuberances and not settle in the crevices in layers as I had supposed.
I don't think anyone proved that it has to be that way. It depends on the thickness of the materials, how much they compact and what the currents are doing.
You cannot dispute that these are sedimentary structures.
However, the layers don't fit my scenario either since they would have been disturbed by the scraping of the "picket" shapes illustrated in your drawing.
Exactly. The irregularities prevent slip.
That suggests that neither explanation works.
Once again the structures are demonstrably sedimentary and not tectonic.
However, the drawing is just a drawing, and nothing in the photos corroborates its presentation of layers in the crevices anyway.
The other photos do demonstrate irregular surfaces, infilling of crevices and the lack of a tectonic structure through the sequence of rocks.
Added from your previous post:
OK, you've shown that there's red sandstone in the crevices. Now I have a different take on it. It would have been the scraping of the lower section, irregular as it is now, against the underside of the upper section, that caused the sand to fill those spaces. For one thing it looks like it came off a horizontal layer that was already there, rather than being deposited as loose sediment into the crevices originally, which would de-emphasize the layered effect, which it didn't.
So, the upper plate rocks just happened to fall into the crevices while just happening to maintain their original orientation compared to their source beds above in every case?
Sure, Faith ...
Edited by edge, : No reason given.

This message is a reply to:
 Message 116 by Faith, posted 01-01-2017 1:23 PM Faith has replied

Replies to this message:
 Message 118 by Faith, posted 01-01-2017 5:19 PM edge has replied
 Message 119 by Faith, posted 01-01-2017 6:16 PM edge has replied

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


Message 118 of 202 (796618)
01-01-2017 5:19 PM
Reply to: Message 117 by edge
01-01-2017 1:48 PM


Re: Siccar Point angular unconformity video
At this point I just want to ask, What on earth do you mean by a "tectonic structure" and why can't there be both sedimentary and tectonic features at Siccar Point? This is utter gobbledygook, as well as a brand-new subject never mentioned before.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 117 by edge, posted 01-01-2017 1:48 PM edge has replied

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


Message 119 of 202 (796619)
01-01-2017 6:16 PM
Reply to: Message 117 by edge
01-01-2017 1:48 PM


Re: Siccar Point angular unconformity video
Another point: if you want to argue that the layering in the crevices proves deposition occurred after the lower irregular section had been there for a while, ...
I'm not, I'm just saying that things are not as you described them.
I'm aware of all those features, I see them mostly as the result of extreme erosion, the photos however do NOT show layering, infilling yes but not layering.
... I'd point out that some time ago, a couple years by now maybe, HBD proved that sand depositing on an irregular surface would drape over the protuberances and not settle in the crevices in layers as I had supposed.
I don't think anyone proved that it has to be that way. It depends on the thickness of the materials, how much they compact and what the currents are doing.
There is no reason to consider Siccar Point different from the examples discussed there.
You cannot dispute that these are sedimentary structures.
Why would I want to?
However, the layers don't fit my scenario either since they would have been disturbed by the scraping of the "picket" shapes illustrated in your drawing.
Exactly. The irregularities prevent slip.
That isn't what I had in mind. I assume slip still, the tectonic force would be strong enough to cause the same movement I've been describing even in this case, but now the effect of the rough upper edges has to be taken into account, and what that would do is dig into the sand layers above, cause sand to fall into the crevices etc.
That suggests that neither explanation works.
Once again the structures are demonstrably sedimentary and not tectonic.
There is no evidence of layering in the crevices in the photos.
However, the drawing is just a drawing, and nothing in the photos corroborates its presentation of layers in the crevices anyway.
The other photos do demonstrate irregular surfaces, infilling of crevices and the lack of a tectonic structure through the sequence of rocks.
They do not demonstrate layering. And if what you mean by "tectonic structure" is drag folds, I'm taking back my tentative concession, which I intended as politeness more than agreeing with your point. I don't agree with it. The way the friction would have worked the part that would have folded would have been filed down.
Added from your previous post:
OK, you've shown that there's red sandstone in the crevices. Now I have a different take on it. It would have been the scraping of the lower section, irregular as it is now, against the underside of the upper section, that caused the sand to fill those spaces. For one thing it looks like it came off a horizontal layer that was already there, rather than being deposited as loose sediment into the crevices originally, which would de-emphasize the layered effect, which it didn't.
So, the upper plate rocks just happened to fall into the crevices while just happening to maintain their original orientation compared to their source beds above in every case?
The sand was scraped into the crevices, AS I SAID, and just as in all my arguments about how this happened, yes the upper section would maintain its horizontal orientation just as it would if the broken off lower surface was flatter and smoother -- {abe: WHICH I BELIEVE WAS THE CASE AT SICCAR POINT AS IN EVERY OTHER ANGULAR UNCONFORMITY AT THE TIME OF THE TECTONIC MOVEMENT. What is seen now is the result of thousands of years of erosion breaking down the upper ends of the broken lower section along with the upper layers. There is no reason for Siccar to be any different from other similar formations at that point/abe) And as usual, there would have been an enormous weight of strata above, as I've pointed out many times over the course of this discussion from thread to thread, and that resistance to the tectonic movement would maintain the horizontality of the upper section.
Sure, Faith ...
When the discussion devolves into irrationality in this way as it so often does with you, I have little interest in continuing it.
Edited by Faith, : No reason given.

This message is a reply to:
 Message 117 by edge, posted 01-01-2017 1:48 PM edge has replied

Replies to this message:
 Message 123 by edge, posted 01-01-2017 8:58 PM Faith has not replied

  
Tangle
Member
Posts: 9489
From: UK
Joined: 10-07-2011
Member Rating: 4.9


Message 120 of 202 (796620)
01-01-2017 6:38 PM


I've tried really hard but I can't make 'ad hoc' an anagram of 'theory'.

Je suis Charlie. Je suis Ahmed. Je suis Juif. Je suis Parisien.
"Life, don't talk to me about life" - Marvin the Paranoid Android
"Science adjusts it's views based on what's observed.
Faith is the denial of observation so that Belief can be preserved."
- Tim Minchin, in his beat poem, Storm.

  
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