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iceage  Suspended Member (Idle past 5187 days) Posts: 1024 From: Pacific Northwest Joined: |
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Author | Topic: Young earth explanations for Angular Unconformities | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
You're just repeating your Siccar Point fantasy without addressing any of the impossibilities that, after all the time you've spent discussing this, you know exist. Rock doesn't form by drying, buried rock layers cannot tilt without affecting the layers above, and rocks will react to weathering according to their composition and length of exposure, with lower rocks being exposed less long than upper rocks.
--Percy Edited by Percy, : Punctuation.
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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There are two problems with this response. One is that the accepted view of Siccar Point contains no impossibilities because, as was said so long ago, in geology the present is the key to the past. The accepted view of Siccar Point employs nothing more than processes we can observe taking place in the present. We know they're possible because we can see them happening. The second problem is that in a thread titled Young earth explanations for Angular Unconformities you're supposed to be presenting your young Earth explanations for angular unconformities. And anyway, as has been explained to you many times, ignorant rejections are not positive evidence.
You don't have a theory. You don't even have a hypothesis. You have a fairy tale.
Your fantasy is impossible.
Someone misunderstood at some point that the context was sedimentary rock, which does not form by drying. Very few types of rock form by drying, and certainly not sedimentary rock. It forms by being buried under great pressure. As pressure increases unconsolidated sediments become more and more consolidated. It isn't a drying process. I invite correction if I'm wrong about this.
You repeated your claim that the strata were "still damp and malleable from the Flood".
What I recall is you abandoning discussion. You've never explained how layers could tilt while leaving overlying layers unaffected. For one thing it's impossible because it requires material from the tilted layers to simply disappear.
Rocks do not form under water according to standard theory. If they did then the deep sea bottom would be rock instead of calciferous ooze.
This defies rational interpretation. "Stripped down?" "Skeletal form?" "Tectonic forces that tilted the lower layers?" It's nonsense.
What things look like to your very uninformed eye carries no weight. --Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
I wasn't sure where to look in the photo, so consequently I didn't understand this:
--Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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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.
I'm still not sure where on the image I should be looking:
Or were you talking about the Siccar Point image?
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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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
Here's your diagram:
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
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
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:
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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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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The degree of tilt doesn't matter. It's the same problem no matter what the degree of tilt. The missing material has to go somewhere. In the view of standard geology the missing material was once at the surface and was removed by the forces of erosion and carried away toward the lowest elevation (most often the ocean where most sedimentary layers originate) by wind, rain, streams and rivers. Erosion tends to level a landscape, and then when deposition begins again sediments are deposited in mostly flat layers upon the older eroded surface. The boundary between the older layers and the new layers is an unconformity.
Your scenario is impossible, and I can explain why. Here are the sedimentary layers as they originally appeared. I've labeled them A through H:
And here are the layers after E through H rotated 90 degrees to become vertical:
I've labeled as X and Y the regions next to layers E through H. What fills regions X and Y now? Your answer is that material scraped and eroded and broken off from layers D through H should fill region X and Y. But the reality is that X and Y are not filled with material from layers D through H. At the Grand Canyon (where the tilt is much less than 90 degrees) X and Y are filled with Vishnu basement rocks. At Siccar Point X and Y are filled with other sedimentary layers. And as Edge has pointed out, there is also no evidence of shear at the boundary. Once tilted vertical, layers E through H have a limited extent, bounded by layers A through D at the top and by other rock at the bottom. In your scenario the miles of extent of layers have become truncated into a very short distance. Where did all the missing material go? --Percy Edited by Percy, : Grammar.
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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This isn't the point that's being made. No one thinks the layers weren't folded by geologic forces. The point is that when the layers were folded the current overlying layers were not present. There were other layers atop the folded layers that were folded along with them and then were later eroded away.
Why do you think tectonic forces generated from within the Earth require some sort of counterweight?
It was eroded and carried away to the lowest geologic point (often the ocean) by wind, rain, streams and rivers. It's the same process we see happening all around the world today. The present is the key to the past. It's amazing that after all your time here you still don't know the basics of geology. To disagree with them is one thing, but to not even know them despite years of discussion is unfathomable. --Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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I'm not sure why there's any confusion about this, so I'll just repeat the point, but first here's the image again:
Of course folding is present. No one said folding isn't present.
It's amazing that you don't already understand this. It's very basic geology. Before new layers were deposited atop it, what did you imagine was being eroded away to form the top surface of the angular unconformity? Here's a modified copy of the Siccar Point diagram showing in red where the layers that were eroded away might have been:
All the red layers that I added were eroded away, the sediments carried away to lower elevations like the ocean by wind, rain, streams and rivers. Then the layers visible today atop the angular unconformity were deposited.
Ah, okay. I don't think "counterweight" was the word you were looking for. All it takes is one area being uplifted or subsided more than another to bend or fold layers. That could mean different amounts of force in different areas, or it could mean different amounts of overlying layers, or a combination.
It *does* "form a surface riddled by cracks," but not in the way you're thinking. Erosion and weathering, especially things like rising/falling temperatures and freezing/thawing water, cause minute cracking and flaking of rock, gradually wearing it away particle by particle.
The eroded material is carried away to the lowest elevations, often the ocean, but on its journey it will encounter many local low elevations, and there the eroded material will remain until it piles high enough to continue toward even lower elevations. Any landscape eventually erodes away, and the eroded material it contains eventually reaches a low elevation.
I think we should appreciate all the help we can get from Edge. Hopefully he can confirm what I've told you about angular unconformities, that basic geology believes they form when the higher portions of the tilted layers are eroded away. --Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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What was it you imagined was eroded away when people described the surface of an angular unconformity as forming due to erosion of the higher portions of the tilted layers? This understanding of angular conformities has been around forever and is what everyone has been saying. This is from a 1985 geology textbook in a paragraph describing angular unconformities: quote: Nothing new about it. It's what Hutton surmised when he first saw Siccar Point. Regarding my drawing where I completed the layers of the angular unconformity that had been eroded away:
You included an extremely similar diagram from James Lyle on your blog page titled Angular Unconformities, Part 3: Lyell on how the rocks were tilted:
You had obviously read about geology's very long understanding that the upper portions of tilted layers erode away to form angular unconformities back in 2011 when you wrote that blog page. --Percy Edited by Percy, : Typo.
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
I'm not sure what is meant by "lower sequence", so Faith might not know what is meant, either.
--Percy Edited by Percy, : Grammar.
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
Calling them the lower sequence is fine, but in that case I don't know what you meant by "a whole lot of the lower sequence has been somehow removed." If the lower sequence is the portion below the unconformity, none of it has been removed. I still have a feeling there may still be a terminology issue in play, either that or I'm missing something. --Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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No, Faith, I never said anything like that, and until just now you never said that was your understanding of what I said. You might at least try keeping to a consistent story. Summarizing the big problems with your fantasy scenario, cubic miles of strata cannot disappear without a trace (meaning no remains of rubble or signs of shearing), disturbances to buried strata cannot fail to disturb overlying strata, rocks weather to form the appearance of age according to their composition and length of exposure and not how long ago they formed, and sedimentary rocks do not form by drying. --Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6
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Oh, I see what you're saying. I thought that by "lower sequence" you meant only what exists today, but I see what you mean now. --Percy
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Percy Member Posts: 20833 From: New Hampshire Joined: Member Rating: 2.6 |
The scenario you describe can and does happen. As soon as some strata has been uplifted above the nearby landscape, sediments from the uplifted region will be deposited upon the lower elevations. If the region remains uplifted long enough then even the lower elevations will erode away, potentially leaving no signs of the eroded material in the area. But if the region subsides again before that can happen then the sedimentary deposits may well be preserved, possibly to be exposed again in the future for us to find. Perhaps Edge knows of some examples.
In your scenario the material pushed to the "front" of the formation while buried is unlikely to be the same part that erosion just happens to reveal.
That's scree and has nothing to do with the deformation of strata. It forms after exposure due to erosive and weathering forces.
This contradicts what you said just before about the rubble being at the "front...in all the pictures," but regardless this is just the kind of evidence you need to find, cubic miles of broken off rubble from the strata of the angular unconformity. I liked the label Edge had for it, the "room" problem. Basically it means that everything has to be somewhere - it can't just disappear. --Percy
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