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Author Topic:   Young earth explanations for Angular Unconformities
JonF
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Posts: 4001
Joined: 06-23-2003
Member Rating: 3.1


Message 121 of 202 (796626)
01-01-2017 8:23 PM
Reply to: Message 118 by Faith
01-01-2017 5:19 PM


Re: Siccar Point angular unconformity video
why can't there be both sedimentary and tectonic features at Siccar Point?

There could be. There aren't any.


This message is a reply to:
 Message 118 by Faith, posted 01-01-2017 5:19 PM Faith has not yet responded

  
edge
Member
Posts: 4002
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 3.0


Message 122 of 202 (796627)
01-01-2017 8:49 PM
Reply to: Message 118 by Faith
01-01-2017 5:19 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" ...

A structure is usually a planar feature in a rock mass.

A tectonic structure would be such a feature caused by tectonism.

In this case, it would be a fault plane, that we would describe as a detachment surface that cuts through the rock mass and its various elements (such as bedding planes, clasts, fossils, etc.) There is no such thing at Siccar.

Such a detachment would have to be very obvious if it were involved in the type of deformation that you are describing in the lower block because of the total amount of strain shown by folding.

... and why can't there be both sedimentary and tectonic features at Siccar Point?

Theoretically, we might see a fold axis, but I have never seen it in any photographs of the location.

This is utter gobbledygook, as well as a brand-new subject never mentioned before.

Actually, it makes sense even if it is not commonly used.

Edited by edge, : No reason given.


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 Message 118 by Faith, posted 01-01-2017 5:19 PM Faith has not yet responded

  
edge
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Posts: 4002
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 3.0


Message 123 of 202 (796628)
01-01-2017 8:58 PM
Reply to: Message 119 by Faith
01-01-2017 6:16 PM


Re: Siccar Point angular unconformity video
The sand was scraped into the crevices, AS I SAID, and just as in all my arguments about how this happened, ...

Then please show us the surface formed by scraping. And explain how the layering is concordant with the overlying rocks in every case.

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.

This is not uncommon for photographs at Siccar Point. Unfortunately, no one has been trying to show you the details.

However, I am certain that I have shown you such situations at other locations, some of which were at the Great Unconformity.

When the discussion devolves into irrationality in this way as it so often does with you, I have little interest in continuing it.

I can see that you are, once again, becoming frustrated with your lack of geological knowledge. With that in mind, I will try to refrain from posting responding to you unless you have a direct question.
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 Message 119 by Faith, posted 01-01-2017 6:16 PM Faith has not yet responded

  
Faith
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Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 124 of 202 (796632)
01-02-2017 12:03 AM


No tectonic features?
WHAT ABOUT THE UPRIGHT STRATA FOR PETE'S SAKE?

Good grief.

And once again, what I am frustrated with is your game-playing sabotage of communication.

Edited by Faith, : No reason given.


Replies to this message:
 Message 125 by edge, posted 01-02-2017 5:25 AM Faith has responded

    
edge
Member
Posts: 4002
From: Colorado, USA
Joined: 01-09-2002
Member Rating: 3.0


Message 125 of 202 (796633)
01-02-2017 5:25 AM
Reply to: Message 124 by Faith
01-02-2017 12:03 AM


Re: No tectonic features?
WHAT ABOUT THE UPRIGHT STRATA FOR PETE'S SAKE?

Do you see a fold?

All I see are bedding planes.

Those would be sedimentary structures.


This message is a reply to:
 Message 124 by Faith, posted 01-02-2017 12:03 AM Faith has responded

Replies to this message:
 Message 127 by Faith, posted 01-02-2017 10:40 AM edge has not yet responded

  
Percy
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Posts: 16340
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.4


(1)
Message 126 of 202 (796635)
01-02-2017 8:12 AM
Reply to: Message 112 by edge
01-01-2017 11:39 AM


edge writes:

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.

I'm not so sure that this is what Faith believes. She thinks that buried layers like this:

Can become tilted by tectonic forces to look like this:

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:

Clearly it's impossible for so much material to disappear into thin air, and so her scenario could never happen, and so it could never form a shear zone. If I'm wrong about this please let me know. I just think it important that we all are talking about the same scenario. Faith is often so vague that there's a tendency to fill in the blanks with ideas she never imagined.

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.

I'm still not sure where on the image I should be looking:

Or were you talking about the Siccar Point image?

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.

Faith may not have followed your argument about the degree of mechanical action, and I may not either. You seem to be drawing a contrast between relatively fast erosion (high mechanical action) that leaves a clean and new looking surface, versus weathering which results from long exposure with small scale erosion (low mechanical action) that results in the aged appearance we're familiar with in some rocks such as at Siccar Point. If I have that right then I get it, but I'm not sure Faith does.

--Percy


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 Message 112 by edge, posted 01-01-2017 11:39 AM edge has responded

Replies to this message:
 Message 130 by Faith, posted 01-02-2017 11:27 AM Percy has responded
 Message 133 by petrophysics1, posted 01-02-2017 3:08 PM Percy has responded
 Message 139 by edge, posted 01-02-2017 10:39 PM Percy has acknowledged this reply

    
Faith
Member
Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 127 of 202 (796643)
01-02-2017 10:40 AM
Reply to: Message 125 by edge
01-02-2017 5:25 AM


Re: No tectonic features?
Do you see a fold?

All I see are bedding planes.

Those would be sedimentary structures.

I'm sorry, you are making absolutely no sense.

Please explain how you think the lower section at Siccar Point got into its upright position. How did the layers get broken off as they did, and where did the excess material go?

Edited by Faith, : No reason given.


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Faith
Member
Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 128 of 202 (796645)
01-02-2017 10:50 AM
Reply to: Message 112 by edge
01-01-2017 11:39 AM


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.

This makes no sense to me. First of all I did not say there is a LACK of weathering below the unconformity, I said the opposite, I said both upper and lower sections look equally weathered to me, which is to argue that the usual old-earth interpretation doesn't work. You answered that they were deposited close enough together to eliminate that problem, on the basis of some "shoreline" theory, for which you gave no evidence.

I did argue that the apparent lack of difference in weathering is an argument for my tectonic formation/shearing theory because the layers both above and below the unconformity would have already been in place at that time.


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Faith
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Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


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 yet responded

    
Faith
Member
Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


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 responded

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

    
Faith
Member
Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


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 responded

Replies to this message:
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Percy
Member
Posts: 16340
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.4


Message 132 of 202 (796654)
01-02-2017 2:47 PM
Reply to: Message 130 by Faith
01-02-2017 11:27 AM


Faith writes:

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.

Here's your diagram:

First, the strata below the unconformity happen to be straight upright at Siccar Point, not tilted as you've illustrated,...

This is incorrect. As you can see in your own diagram, some of the layers are nearly upright, some are tilted, 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 because it requires cubic miles of material to simply disappear into thin air.

--Percy


This message is a reply to:
 Message 130 by Faith, posted 01-02-2017 11:27 AM Faith has responded

Replies to this message:
 Message 135 by Faith, posted 01-02-2017 7:40 PM Percy has responded
 Message 138 by edge, posted 01-02-2017 10:33 PM Percy has acknowledged this reply

    
petrophysics1
Inactive Member


Message 133 of 202 (796655)
01-02-2017 3:08 PM
Reply to: Message 126 by Percy
01-02-2017 8:12 AM


Edge's photo of the GC
Percy,

Google "spheroidal weathering images", now look at Edge's photo. The lower pinkish rocks are the granite, do you see the spheroidal weathering in the granite now? The granite was being weathered chemically but the weathered material was not being removed.

To weather a granite this deeply requires a substantial amount of time. It is an interesting photo because it is a picture of an unconformity that clearly shows a prolonged period of weathering before the later deposition. If everything weathered has been removed this is not as clearly shown.


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

Replies to this message:
 Message 134 by Percy, posted 01-02-2017 4:37 PM petrophysics1 has not yet responded

  
Percy
Member
Posts: 16340
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.4


Message 134 of 202 (796661)
01-02-2017 4:37 PM
Reply to: Message 133 by petrophysics1
01-02-2017 3:08 PM


Re: Edge's photo of the GC
petrophysics writes:

Google "spheroidal weathering images", now look at Edge's photo. The lower pinkish rocks are the granite, do you see the spheroidal weathering in the granite now? The granite was being weathered chemically but the weathered material was not being removed.

Oh, yes, I could see the eroded granite boulders, but I think I didn't ask the question clearly enough, didn't quote enough or say enough. Trying again, here's Edge's image from Message 107:

This is the passage from Edge where I didn't know where to look in the image:

edge writes:

Note the weathering rinds that formed along fractures in the Pikes Peak Granite, ostensibly before the overlying Cambrian sandstone was deposited.

Is Edge referring to those granite boulders when he says, "weathering rinds"? What fractures is he referring to, the ones between layers, or the fracture in the layer to the right of the boulders? Anyway, because I didn't understand this paragraph, I wasn't sure how to interpret the next one either.

--Percy


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Faith
Member
Posts: 26759
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


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.


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 Message 132 by Percy, posted 01-02-2017 2:47 PM Percy has responded

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