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I've been saying from the point I entered this thread that the upper and lower segments of the Siccar unconformity look about equally weathered. The appearance of weathering (or erosion or whatever is the cause of the obvious breakdown of the rocks into their splintery form) is the only comparison I've commented on
Aside from the subjectivity (and failing to check that the rocks are equally hard) it does seem very clear that you are looking at an exposed cross-section rather than the surface.
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The point has been from the beginning that I see no evidence of the usual interpretation of angular unconformities, that there is a difference of millions of years between the tilted lower portion and the upper horizontal portion of such formations.
You are the only one who fails to see it. The evidence that there has been major erosion between the folding and the deposition of the strata above the unconformity is quite clear.
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If that were the case, I argued, the lower section should be utterly reduced to a small pile of splintery rock at a location like Siccar Point with the constant battering of the elements. MILLIONS of years.
Given the fact that quite large amounts of rock were lost between the folding and deposition starting - and that you would need to know that the conditions causing the erosion were so harsh that we should expect more - that really doesn't seem to be much of an objection. Without good estimates of how much has been lost and how much should have been lost you are just guessing.
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The upper segment is identified as Devonian, the lower as Silurian, the usual difference in age between these time periods being in the millions.
The age of the fold would seem far more relevant than the time the greenwacke was deposited. Exposure time is what matters, not age.
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How long does it take? How long has the upper section been there? Even that section should have been reduced to rubble by now according to the usual time spans proposed by standard geology.
As I point out above, that is no more than a wild guess. (However I will note that an inability to account for observed erosion in the Biblical timescale was one of the earliest clues to the fact that the Earth was much older than the Bible suggested)
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The topic is still pretty confused it seems to me.
The confusion is mostly yours.