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Author Topic:   Evidence that the Great Unconformity did not Form Before the Strata above it
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Message 1367 of 1939 (756530)
04-22-2015 6:54 AM
Reply to: Message 1366 by Faith
04-21-2015 11:33 PM


Re: can loose sediments "drape?"
Faith writes:
OK, to try to simplify: What I have in mind is that IN THE FLUID STATE when depositing, as the Strata appear to have been deposited --- whether that means "liquid" as in water-borne, which I usually assume it means, or "fluid" in some other sense --- anyway, in the FLUID state, or as "loose sediments" which is another term I've used, for the state of being unconsolidated grains...
I'd like to suggest you use more standard terminology. Keeping this simple, sediments are solid grains of material weathered off rock. Sediments have no liquid state, no fluid state. Sediments are solids. But sediments, especially when they're tiny grains, can be suspended in water (and in air and ice, but I'm keeping this simple), and of course the more active the water the larger the grains of sediment can be while remaining in suspension. As water becomes less active sediments will fall out of suspension, the largest grains first, and of course in still water all the sediments will eventually fall out of suspension. Sedimentary material that falls out of suspension accumulates on the bottom.
A loose layer of sediments on the bottom is given the term unconsolidated. The term "unconsolidated" does not apply to sedimentary material that is in suspension.
in THAT state I expect them ALWAYS to deposit horizontally on any surface, any incline, and NOT 'drape" over objects AT ALL.
Sediments will remain where they fall unless the slope of the surface is too steep given friction, shape, adherence, etc.
They should deposit horizontally AROUND objects, they should deposit deeper in depressions and more shallowly where the base surface is higher and always produce a horizontal surface of their own.
No, sediments will not "always produce a horizontal surface of their own." Here's an illustration of an experiment you could carry out in your sedimentation tank. Arrange the sand to slope as shown in (a), with the steeper slope on the left being as steep as can be maintained with sand under water, and the less steep slope on the right. Now sprinkle sand evenly on the surface of the water, preferably a different colored sand. If you don't have different colored sand then trace the original sand height on the glass of the tank with a marker:
What you imagine should happen is shown in (b), a flat horizontal layer of sand on the bottom.
What will actually happen is shown in (c). The sand slides down the steep slope to the lowest point, making the sand deeper there, but the sand on the less steep slope stays precisely where it falls.
I really don't think there is any experiment we could do to try to get loose sediments to drape IN LAYERS, which is what you all think the MacKee diagrams show. But some kind of proof is needed.
Proof shouldn't be hard to come by because you have the means in your possession - Coragyps sent them to you. Sediments falling out of suspension onto some surface will stay put unless the slope of the surface is too steep given friction, shape, adherence, etc. Perform some experiments and you'll see this yourself.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1366 by Faith, posted 04-21-2015 11:33 PM Faith has replied

Replies to this message:
 Message 1368 by Faith, posted 04-22-2015 8:25 AM Admin has seen this message but not replied
 Message 1376 by Faith, posted 04-22-2015 9:33 AM Admin has replied

  
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Message 1380 of 1939 (756549)
04-22-2015 10:35 AM
Reply to: Message 1376 by Faith
04-22-2015 9:33 AM


Moderator Ruling
Faith writes:
Sediments have no liquid state, no fluid state. Sediments are solids.
See Message 1374. When the moderator resorts to pedantic putdowns it's time to give up the position.
I was simply defining terms. There was nothing pedantic about it, and it certainly wasn't a putdown.
The tone of your recent messages tells me that you're passing through one of your "find fault with everyone and everything" phases. I don't think it is a good idea for you to be posting right now and so have suspended you for a very short period, one hour.
My moderator ruling is that it is important to agree upon terminology, and so I will try to encourage that as much as possible.
To everyone else: Please help keep this thread on an even keel by approaching Faith's recent posts in as generous a frame of mind as possible.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1376 by Faith, posted 04-22-2015 9:33 AM Faith has not replied

  
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Message 1391 of 1939 (756562)
04-22-2015 5:03 PM
Reply to: Message 1390 by Faith
04-22-2015 4:48 PM


Faith Suspended One Hour Again
Hi Faith,
Faith writes:
Message 1366
This is really unconstructive, so I'm going to suspend you for an hour again.
There was already a reply to that message. You dismissed it in two separate messages, in one saying, among other things, that the experiment described wasn't about something you wanted to test, and in the other accusing me of "pedantic putdowns".

--Percy
EvC Forum Director

This message is a reply to:
 Message 1390 by Faith, posted 04-22-2015 4:48 PM Faith has not replied

  
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Message 1409 of 1939 (756581)
04-23-2015 6:54 AM
Reply to: Message 1399 by Faith
04-23-2015 12:42 AM


Re: draped sandstone continued
Hi Faith,
I am, as always, reading forward sequentially and responding as I go as needed. In this case I'm seeking clarification. Since I haven't yet read the messages after this one I have no way of knowing if the issues I'm going to raise have already been clarified, but if they have then please just ignore this message.
Another term I remember from soils class is plasticity, where material is not loose sand or gravel, nor is it solidified rock. It behaves in a plastic manner, deforming under stress\pressure and not rebounding when stress\pressure is removed. It also would not flow down slope to level out due to cohesion and internal friction. Wet clay is an example.
Which is the only condition I've been saying could produce "draped" layers over objects, whereas sediments in their original "fluid" form would not do this.
I don't recall you ever saying that compression of layers around a hard object like a rock would cause draped sedimentary layers. I thought your position was that a dropstone falling and embedding itself into sedimentary layers would immediately produce this appearance:
Uh, did you alter the above image? It now has a couple lines through the top three layers, I assume to indicate that the dropstone disrupted them while passing through. I don't recall seeing them before. Perhaps I simply missed them, but now I have to comment that no such disruption appears in the layers above dropstones, indicating that they did not pass through those layers but instead had sedimentary layers deposited above them after they fell:
About this image:
Since you now concede that sedimentary layers can deposit evenly on a slope, what is it you see in this image that leads you to conclude it was originally horizontal and only tilted later?

--Percy
EvC Forum Director

This message is a reply to:
 Message 1399 by Faith, posted 04-23-2015 12:42 AM Faith has replied

Replies to this message:
 Message 1411 by Faith, posted 04-23-2015 7:24 AM Admin has replied
 Message 1412 by Faith, posted 04-23-2015 7:32 AM Admin has seen this message but not replied

  
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Message 1413 of 1939 (756585)
04-23-2015 9:07 AM
Reply to: Message 1410 by Faith
04-23-2015 7:10 AM


Re: McKee diagram in photo?
Faith writes:
From Google Images a photo (below) that I think pictures the area of two of the diagrams by McKee, (b) and (e), which I found by searching on the location references at the bottom of the page. But it's one of those touristy pictures that is more interested in the sunset than the formation so you only get a hint of the Tapeats layers.
If you or anyone can see sloping sedimentary layers following the contours of underlying Archean layers, please describe where to look in this image:

--Percy
EvC Forum Director

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Message 1414 of 1939 (756586)
04-23-2015 9:28 AM
Reply to: Message 1411 by Faith
04-23-2015 7:24 AM


Re: draped sandstone continued
Faith writes:
The fact that it's a FORMED LAYER that had to have sagged AFTER ITS FORMATION. As I've said five billion times already.
I can tell by your insistent tone that you think this answers the question, but I have no idea why. It still leaves me wondering what in the image is telling you that the circled layers had to have sagged only after they were deposited:
All I said was that I don't care and it doesn't interest me whether sediments can deposit on a slope or not,...
But just a short while ago you were insisting that Steno 350 years ago was the final word on horizontality, and you called people who disagreed insane and the science a fraud. You seemed to care a great deal, and it seems very relevant now to how you know those layers weren't already sloped when they formed. I'm not taking a position either way - I'm just explaining that it's important to the discussion that we understand how you know they were originally horizontal and only tilted later.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1411 by Faith, posted 04-23-2015 7:24 AM Faith has replied

Replies to this message:
 Message 1425 by Faith, posted 04-23-2015 2:25 PM Admin has replied

  
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Message 1435 of 1939 (756620)
04-23-2015 8:35 PM
Reply to: Message 1425 by Faith
04-23-2015 2:25 PM


Re: draped sandstone continued
Faith writes:
It's frustrating to keep being dragged back to that basic argument while the issues that concern me get ignored.
Say you really, really want to build a house. You're really anxious to get on with things and build that house, but people keep holding you up and bothering you with details that you don't care about like laying a foundation. Naturally you find it very frustrating, but only until you come to understand the importance of laying a foundation.
It's the same here. You keep getting dragged back to basic points because they're the foundation for the issues you're so concerned about. Naturally you find it very frustrating, but they're as important to your issues as a foundation is to a house.
In this case I've marked some indicators of the deformation of the rocks. The arrows point to the contacts between the layers, showing that the layers are separated from each other, not laid neatly one on top of the other as you see in fresh deposition; and I circled places where the rocks broke at the edge, or "hinge" if you will, of the area to the left that sags away from the central area.
This is a road cut. Any separation of layers and broken rocks are a result of cutting and/or blasting the rock to make the road cut and of any subsequent weathering due to wind, rain, snow and freeze/thaw cycles.
The larger circled area shows the general disturbance that occurred in the stack at that point,...
The larger circled area shows a bush and discolored rock with a more irregular surface, but that's a function of making the road cut. There's nothing to indicate a tectonic disturbance,
...and the smaller circled area shows where the layer itself was broken.
The smaller circled area shows rock that was broken when the road cut was created or maybe by later weathering, and a shadow. Again, nothing to indicate a tectonic disturbance.
So there's no evidence that tectonic activity changed the tilt of the layers, so the original question remains. What leads you to believe the layers must originally have been horizontal?

--Percy
EvC Forum Director

This message is a reply to:
 Message 1425 by Faith, posted 04-23-2015 2:25 PM Faith has replied

Replies to this message:
 Message 1446 by Faith, posted 04-24-2015 6:52 AM Admin has replied

  
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Posts: 13046
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Message 1450 of 1939 (756638)
04-24-2015 10:12 AM
Reply to: Message 1446 by Faith
04-24-2015 6:52 AM


Re: draped sandstone continued
Hi Faith,
I was just trying to be a facilitator when I asked you to clarify why you believed you saw evidence of tectonic disturbance in that road cut. You replied by stating that the shape of the broken rocks of the road cut were evidence of tectonic disturbance. I'll continue to try to facilitate on simple issues, but before getting into this issue further I just want to be sure you're aware that you've taken a position that will seem to most people to be wrong, irrational and perverse, similar to your position on the appearance of the exposed layers at Siccar Point that were just a result of weathering but that you thought told you something more.
So just to be safe I want to caution everyone to remain civil and focused on the topic.
Faith writes:
This is a road cut. Any separation of layers and broken rocks are a result of cutting and/or blasting the rock to make the road cut and of any subsequent weathering due to wind, rain, snow and freeze/thaw cycles.
Nope. The actual evidence I've been discussing does not support that idea. The separation or overhang as JonF says it really is, without offering evidence or reasoning, occurred to SOFT rock that sagged due to its softness, and any blasting or cutting would have been done in lithified rock and shattered it, not separated it.
When you say the layers were separated, do you mean that while still buried and before the road cut was made that the layers were no longer immediately adjacent to each other, that there was a space between them? Or do you mean they were no longer bound to each other?
Here is the image again:
Do you see the evenly spaced vertical channels? These are the drill holes into which explosive charges like dynamite were placed. Here's a video of blasting for road cuts:
The rock was blasted away, then the loose rock was picked up and carted away by heavy equipment that must have repeatedly banged into the rock face, then weathering set in on the exposed rock. The shape of the surface of the rock left behind cannot tell you anything about tectonic forces.
Discolorations that spans multiple rock layers are usually due to chemicals leaching out of the rocks and/or soil above when it rains and staining the rock surface as it runs down (Edge's comments on the discoloration in the larger circled area would be helpful).

--Percy
EvC Forum Director

This message is a reply to:
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(1)
Message 1458 of 1939 (756646)
04-24-2015 11:56 AM
Reply to: Message 1457 by edge
04-24-2015 11:37 AM


Drag Folds Defined
The recent discussion about drag folds indicates that some participants may not be aware that drag folds are associated with faults. I thought a definition might be helpful, so just to help things along, here's a definition from About.com:
About.com writes:
Folding is a deep and complex subject in geology. Drag folds are one of the simpler types of fold. They occur in conjunction with faults, and they represent the bending of rock before it breaks. In this example the fault is a thrust fault with the top side (the hangingwall) moving to the right, and the bottom side (the footwall) displays drag folding. Probably the folding occurred when the rock was deeply buried. Later, when the rock was being uncovered during its rise to form the Oakland Hills in the San Francisco Bay area, further movement on the fault shattered the rock in the hangingwall and destroyed its drag folds.
It may seem, intuitively, that the rock in a drag fold is bent by being dragged along the fault surfacehence the namebut in fact drag folding must precede the actual breakage of the rock in a fault. Like everything else, rocks prefer to bend first before they break. In most cases, the direction of folding is toward the direction of movement on the fault.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1457 by edge, posted 04-24-2015 11:37 AM edge has replied

Replies to this message:
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Message 1467 of 1939 (756660)
04-24-2015 2:20 PM
Reply to: Message 1466 by Faith
04-24-2015 1:51 PM


Moderator Facilitation
Faith writes:
No, it's your memory that's bad. I have never mentioned drag folds in relation to the road cut layers,. There are none there. They are very prominent in the McKee drawings, however, and that is what I was talking about.
I think you and Edge are both talking about this diagram:
Because it's so easy to include an image in a message and entails almost no overhead, I encourage everyone to include images under discussion in every message.
Edge can correct me if I have this wrong, but I believe he's saying that since you think you see drag folds in one or more of the diagrams in this image, and since drag folds are associated with faults, where do you see the faults that should be present if indeed there are drag folds.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1466 by Faith, posted 04-24-2015 1:51 PM Faith has not replied

Replies to this message:
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Message 1468 of 1939 (756662)
04-24-2015 2:28 PM
Reply to: Message 1463 by Faith
04-24-2015 1:25 PM


Re: draped sandstone continued
Here's your version of the image:
TAD, HBD and everyone else can see that to the left the lighter colored layers above your red line tilt downward, and to the right they are mostly level. The question concerns what you see in the diagram that leads you to believe that the layers were originally horizontal.
Looking at this message and the next one, I'm going to help you save your eyes and your sanity by suspending you for a couple hours.

--Percy
EvC Forum Director

This message is a reply to:
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(1)
Message 1472 of 1939 (756672)
04-24-2015 6:10 PM


Why the Circled Rock is Different
I think I know why the rock in the larger circled area (excluding the bush) seems more irregular and extends outward more than the rest of the rock of the road cut. Here's the image:
The blast holes extend all the way down to the top of the light colored sandstone layer everywhere except in that area. For some reason they just didn't drill the holes as deep there. Note that the light colored standstone layer also extends out further from the rest of rockface in this area.
Here's the distance view that clearly shows the blast holes extending all the way down to the top of the light colored sandstone layer everywhere on the road cut except in that area:
The image doesn't show any drill holes in the light colored sandstone layers, but my guess is that the drill holes extended through them also (except in the aforementioned area), but that because it is softer the holes were completely obliterated there.

--Percy
EvC Forum Director

Replies to this message:
 Message 1474 by edge, posted 04-24-2015 6:17 PM Admin has replied
 Message 1477 by Faith, posted 04-25-2015 7:35 AM Admin has replied

  
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Message 1476 of 1939 (756682)
04-24-2015 9:04 PM
Reply to: Message 1474 by edge
04-24-2015 6:17 PM


Re: Why the Circled Rock is Different
edge writes:
If we were there, it would all be much clearer. Time for a field trip...
It's a few miles east of Alexandria Bay, NY, on Route 12. I found it using street view with Google Maps. If someone lives up that way I can give them the exact location.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1474 by edge, posted 04-24-2015 6:17 PM edge has not replied

  
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Message 1481 of 1939 (756697)
04-25-2015 9:09 AM
Reply to: Message 1477 by Faith
04-25-2015 7:35 AM


Re: Why the Circled Rock is Different
Of course it would be much better to be there, but I placed blue lines slightly to the right of every outline of a blasting hole that I could make out:
Although Google Street View is low resolution, it does allow you to view this feature from further to the left and right, and it appears possible that the bump upward of the red line in the right hand third of the image is misdrawn. It should perhaps remain straight at that point. But again, it would be better to be there.
But there's a more fundamental question. The rock face is the result of dynamite blasting. Why should how the rock face looks after being blasted indicate anything about tectonic forces and movements? This seems like just another one of those absurd ideas that you insist upon when you want to stop discussing something else.
I just suspended you for 24 hours for Message 1480.
AbE: Faith asked me to change the lines I drrew on the image to yellow, so I did.
Edited by Admin, : AbE.

--Percy
EvC Forum Director

This message is a reply to:
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Replies to this message:
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 Message 1488 by edge, posted 04-25-2015 11:03 AM Admin has seen this message but not replied
 Message 1495 by JonF, posted 04-25-2015 3:16 PM Admin has seen this message but not replied

  
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Posts: 13046
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Message 1482 of 1939 (756698)
04-25-2015 9:22 AM
Reply to: Message 1478 by Faith
04-25-2015 8:43 AM


Faith Suspended 24 Hours
Faith writes:
Then you are missing one of my main points. Nothing new there of course, and I'm too exhausted and discouraged by this excuse for a debate to care much what sort of mess you make of my arguments any more. The distinction is huge and central to my point. Figure it out or don't.
I'm asking everyone in this thread to patiently explain their points as many times as necessary.
Not that you could possibly consider anything I say as meaning anything since you are the only one here, along with your little gaggle of sycophants of course, who knows anything about anything.
Another suspension coming up no doubt.
I hadn't read this message yet when I suspended you for Message 1480, but very good forecasting by you here.
But I do hope someone will post the picture of the road cut with drill or blast holes circled whether or not I return.
Your wish has been granted. See Message 1481.

--Percy
EvC Forum Director

This message is a reply to:
 Message 1478 by Faith, posted 04-25-2015 8:43 AM Faith has not replied

  
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