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Faith  Suspended Member (Idle past 1466 days) Posts: 35298 From: Nevada, USA Joined: |
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Author | Topic: Evidence that the Great Unconformity did not Form Before the Strata above it | |||||||||||||||||||||||||||||||||||||||||||
edge Member (Idle past 1727 days) Posts: 4696 From: Colorado, USA Joined:
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To help move the discussion forward I'm going to attempt to explain the point Edge is making. Edge has in mind a scenario where recently deposited layers are still at the surface (likely a submerged surface) when an object like a rock falls on them. The layers, still unlithified and completely loose in that you could easily dig them up with a trowel, will become deformed in a manner like this image Edge presented earlier:
Yes, the picture shows a point in time where, during sedimentation, a exotic rock dropped out of the water and into soft sediments. If you are careful, you can find the exact point, as recorded by the sediments, when this happened (in a relative sense). The whole reason for bringing up dropstones is that they have a unique interpretation for their motion. Saying that a basement gneiss has moved upward due to some unknown force along some invisible faults or folds, and may or may not have disrupted the upper sediments and created some kind of bedding-plane shear is not a problem with dropstones. They are fairly easy to visualize for most of us. The only force is gravity, and there is no connection to a deep source of uplift. Is this making sense?
The gray rock in the center of the image fell onto already deposited soft sediments and deformed them. Only the layers that are deformed downward were present when the rock fell on them. Sedimentation then continued upon, over and around the rock.
If the sediments draped over the rock were there prior to its emplacement, they would be disrupted. One of the interesting facts here is that this particular event occurred well before the Cambrian Period and is almost certainly due to glacial rafting of the cobble... and we are back to the snowball earth, glacial planation of pre-existing rocks and 'straight, flat unconformities...
The rock could not have been pushed up or down through the layers into this position after they were already there because in that case the layers would be deformed all upward or all downward, including all the layers that the rock would have had to pass through. That the layers are deformed downward for the lower half of the rock and upward for the upward half of the rock conclusively shows what had to have happened.
Yes, during this sedimentation, glaciers were eroding the continents.
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NosyNed Member Posts: 9003 From: Canada Joined: |
I'm still curious about what you meant.
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New Cat's Eye Inactive Member |
I'm still curious about what you meant. Here's what she said in Message 889, in response to me pointing out the consilience of the data:
quote: By "coincidence", she means that scientists have set up the consilience through their subjective interpretations and that it isn't actually real to begin with.
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Admin Director Posts: 13018 From: EvC Forum Joined: Member Rating: 1.9 |
edge writes: If the sediments draped over the rock were there prior to its emplacement, they would be disrupted. It took me a while to arrive at what I think you really meant. Am I correct in thinking that you're describing a hypothetical here? Would it be a correct rephrasing to say, "Had the sediments that in the image are draped over the rock already been in place when the rock fell then they, too, would have been deformed downward. But they're not deformed downward, so therefore they were deposited upon and around the rock after it fell."
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edge Member (Idle past 1727 days) Posts: 4696 From: Colorado, USA Joined: |
It took me a while to arrive at what I think you really meant. Am I correct in thinking that you're describing a hypothetical here? Would it be a correct rephrasing to say, "Had the sediments that in the image are draped over the rock already been in place when the rock fell then they, too, would have been deformed downward. But they're not deformed downward, so therefore they were deposited upon and around the rock after it fell."
Yes, in fact, they would be broken.
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NosyNed Member Posts: 9003 From: Canada Joined:
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I'm still curious as to what you mean by coincidence here.
CatSci thinks that you believe that there isn't any match just that subjective looking at it makes some geologists think that there is one. Is that it? How can measurements made of age of rocks (independently of anything else to do with sea floor motions) be "subjectively" made to match with the positions of formations (like the Hawaiian islands) and the currently measured speed of the ocean floor? Is the speed of the floor measurement wrong?Are the locations of the Hawaiian islands wrong? Did someone change the dates to make the match happen? If any of these happened why haven't the "scientists" of the CRI exposed these errors by measuring correctly? Since it seems crazy to think that any of those things could be wrong and come up with the match I have to assume you mean something else other than what cat sci says. You don't like others saying what you mean so perhaps you can explain in more detail.
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Faith  Suspended Member (Idle past 1466 days) Posts: 35298 From: Nevada, USA Joined: |
It took me a while to arrive at what I think you really meant. Am I correct in thinking that you're describing a hypothetical here? Would it be a correct rephrasing to say, "Had the sediments that in the image are draped over the rock already been in place when the rock fell then they, too, would have been deformed downward. But they're not deformed downward, so therefore they were deposited upon and around the rock after it fell."
Yes, in fact, they would be broken. Not if they were soft enough to stretch, just as the bottom layer did, and the appearance of softness of both top and bottom looks identical. My objection to the interpretation is the usual: loose sediments would not form a layer over the rock but would butt into it.
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edge Member (Idle past 1727 days) Posts: 4696 From: Colorado, USA Joined:
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Not if they were soft enough to stretch, just as the bottom layer did, and the appearance of softness of both top and bottom looks identical.
Except that the rock would have to pass through the upper layers in your scenario, completely disrupting, not bending them. And yes, the various layers were probably comparable in strength. So, what? They are not deformed to the same degree, nor in the same sense of deformation (up versus down).
My objection to the interpretation is the usual: loose sediments would not form a layer over the rock but would butt into it.
Well, clearly they didn't. And you have no argument that the rock went through the upper layers to get where it is. Is this as obscure to most people as it is to Faith?
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herebedragons Member (Idle past 879 days) Posts: 1517 From: Michigan Joined: |
Is this as obscure to most people as it is to Faith? No, in fact it is so glaringly obvious that I keep thinking there must be some weird misunderstanding going on here (from one side or the other), but once again, I can't figure out what it is. HBDWhoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca "Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem. Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.
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Admin Director Posts: 13018 From: EvC Forum Joined: Member Rating: 1.9 |
edge writes: Is this as obscure to most people as it is to Faith? I don't think it's really obscure to Faith, but more that she has a different scenario so firmly in mind that she doesn't see the one you're attempting to describe. It does feel to me that it should be possible to supply sufficient additional clarity to get your point across.
Except that the rock would have to pass through the upper layers in your scenario, completely disrupting, not bending them. It might help to explain what "disrupt" means in this context. What should "disrupted" layers look like? Several times I've been expecting that you might confirm my own expectation that the layers above the rock could not possibly have been deflected upward as the rock passed downward through them, but you haven't done that, instead preferring to describe them only as "disrupted." Is my own understanding at fault? Also, I expected that the layers where the rock passed through the layers above that they would no longer exist in the distinct form that we see in various images. A little ways above the rock the layers appear completely undisturbed, but like a nail fired too fast through layers of plywood or a bullet passing through a book, it seems like there should be a very distinct record of its passage.
And yes, the various layers were probably comparable in strength. So, what? When Faith said that the layers above and below the rock appeared equally soft, I think she meant that in the sense that during the flood the layers were incompletely lithified and still soft, to the point where objects like rocks could pass easily through them.
They are not deformed to the same degree, nor in the same sense of deformation (up versus down). I think some more detail concerning the implications of the differences in deformation of the layers above the rock versus the layers below might be helpful. It might help if Faith were willing to comment on the case where a rock has fallen from a melting glacier, impacting on the sedimentary layers of the sea bottom. How would she tell the difference between these two scenarios:
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edge Member (Idle past 1727 days) Posts: 4696 From: Colorado, USA Joined: |
I don't think it's really obscure to Faith, but more that she has a different scenario so firmly in mind that she doesn't see the one you're attempting to describe. It does feel to me that it should be possible to supply sufficient additional clarity to get your point across.
You think that more information would satisfy Faith, somehow? Or are you talking about everyone else? Normally, I would expect people to ask questions if there is something that they don't understand. Oh, well...
It might help to explain what "disrupt" means in this context. What should "disrupted" layers look like? From MW Online: 1 a : to break apart : ruptureb : to throw into disorder Several times I've been expecting that you might confirm my own expectation that the layers above the rock could not possibly have been deflected upward as the rock passed downward through them, but you haven't done that, instead preferring to describe them only as "disrupted." Is my own understanding at fault?
I will explain things more completely in the future.
Also, I expected that the layers where the rock passed through the layers above that they would no longer exist in the distinct form that we see in various images. A little ways above the rock the layers appear completely undisturbed, but like a nail fired too fast through layers of plywood or a bullet passing through a book, it seems like there should be a very distinct record of its passage.
I'd go with that.
When Faith said that the layers above and below the rock appeared equally soft, I think she meant that in the sense that during the flood the layers were incompletely lithified and still soft, to the point where objects like rocks could pass easily through them.
Apparently. But I'm not sure why that makes any difference. ABE: I think some more detail concerning the implications of the differences in deformation of the layers above the rock versus the layers below might be helpful.
I think HBD explained this pretty well. The lower layers are folded downward, while the upper layers are folded upward. How does this happen? Did the rock grow in place? If so, why more deformation downward when up would be the best way to relieve over-pressures of a growing rock? Edited by edge, : No reason given.
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herebedragons Member (Idle past 879 days) Posts: 1517 From: Michigan Joined:
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I just want to make sure we are all talking about the same thing. Here is the order of events we see in this dropstone image:
Sediment was deposited to the level of the red line in roughly horizontal layers.
A stone fell from above, distorting the layers that were already there.
Finally, the red layers were deposited on top of the older layers and the stone. The layer marked with yellow "X"s was not there at this time.
Not if they were soft enough to stretch You are not suggesting they were elastic are you? So they would go back to their original shape after deforming? They stretched down and then sprang back up over the stone?
the appearance of softness of both top and bottom looks identical. This doesn't really have much meaning. What does "soft" stone look like? The bottom is deformed down, the top is deformed up.
loose sediments would not form a layer over the rock but would butt into it. So what would you do to demonstrate this is true? I have shown you how and why loose sediment will stick to an incline. We know it happens in sand dunes, even in underwater dunes. Why would it NOT form small slopes on either side of the stone that is projecting above the present layers? HBD Edited by herebedragons, : typoWhoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca "Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem. Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.
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Tangle Member Posts: 9504 From: UK Joined: Member Rating: 4.7
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Here's another one that seems even more obvious.
I'm struggling to think of any way that doesn't represent a heavy object falling into semi-solid layers of sediment, then new layer forming above it. The layer denoted by the arrow seems to have been almost liquid. One thing that is certain - that object was not pushed up from below. It's the sort of thing you could easily model using layers of different coloured sand and dropping a marble into it, then adding more layers.Je suis Charlie. Je suis Ahmed. Je suis Juif. 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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Faith  Suspended Member (Idle past 1466 days) Posts: 35298 From: Nevada, USA Joined: |
Since so many have been denying the original horizontality of strata, which I had thought was a well-established principle of Geology (and still do -- the denials are absurd and so destructive of reason it is painful), here's a page that defines strata , and makes clear that Steno's laws were all addressing strata and only strata, and no other kind of geological formation, strata being that stack of originally-horizontal rocks of various sediments we've mostly been discussing on this thread:
STENO'S PRINCIPLES OF STRATIGRAPHY
THE PRINCIPLE OF SUPERPOSITION * In a sequence of strata, any stratum is younger than the sequence of strata on which it rests, and is older than the strata that rest upon it. "...at the time when any given stratum was being formed, all the matter resting upon it was fluid, and, therefore, at the time when the lower stratum was being formed, none of the upper strata existed." Steno, 1669. [Of course I disagree with today’s Old Earth timing of the deposition of the layers, but I certainly agree with the principle itself. It's interesting that he sees them all as fluid]. PRINCIPLE OF INITIAL HORIZONTALITY * Strata are deposited horizontally and then deformed to various attitudes later. "Strata either perpendicular to the horizon or inclined to the horizon were at one time parallel to the horizon." Steno, 1669. PRINCIPLE OF STRATA CONTINUITY * Strata can be assumed to have continued laterally far from where they presently end. "Material forming any stratum were continuous over the surface of the Earth unless some other solid bodies stood in the way." Steno, 1669 PRINCIPLE OF CROSS CUTTING RELATIONSHIPS * Things that cross-cut layers probably postdate them. "If a body or discontinuity cuts across a stratum, it must have formed after that stratum." Steno, 1669
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JonF Member (Idle past 189 days) Posts: 6174 Joined:
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Yup, that's what Steno came up with. And they still are mostly true, but not in all cases. As geologists have learned in the centuries since Steno.
But strata are not defined as horizontal today, because we know better. Stratum Definition & Meaning - Merriam-Webster:
quote: Stratum Definition & Meaning | Dictionary.com:
quote: Just a moment...:
quote: Stratum - Wikipedia:
quote: and there's lots more. So your "I'm saying the definition of strata is that it deposits horizontally" is false. It's your own private and erroneous definition, and you are insisting that the geologists who use their definition are wrong. (Not even going into the fact that "horizontal" is poorly defined and never strictly seen in the field).
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