Re: The Thickness of Richard Forrest


John Harshman wrote:
Seanpit wrote:

Ernest Major wrote:

In message <1149718388.844218.202410@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Seanpit <seanpitnospam@xxxxxxxxxxxxxxxxxxxxxxxxxxx> writes

No Sean. We're talking about the sedimentary structures.
That's what you get when you put all the layers together.
If you push them together so that they occupy a smaller lateral
distance they get thicker.

I am talking about the layers Richard. The sedimentary *layers* do not
get thicker when you reduce the lateral distance in a way that causes
WW-shaped warping of the layers. Again, try it with your pieces of
paper.

But the amount of material to be removed by erosion depends on the
vertical thickness of the ensemble, not the perpendicular thickness of
the strata.


Not when the perpendicular distance of the strata should have been
removed long ago by erosion from atop the underlying crystalline base
rock. I'm not talking about how long it takes to erode the whole
mountain away - only the sedimentary skin that surfaces the underlying
crystalline base rock. Why isn't this basement crystalline rock naked
by now? Why is it still covered by it's layered sedimentary "skin"
coating?

Several problems here. The rocks below the sediment are not associated
with it in origin, and they're mostly metamorphic, not igneous. They
came into contact about 16ma. At some point, they were buried to a depth
of at least 15km. The sedimentary rock at the peak has a different
history, so calling it a "skin" on the underlying rock seems odd. The
rocks of Everest have a very complicated history of faulting,
metamorphism, burial, exhumation, and intrusion. Your simple little
scenario is so naive as to be laughable, but it does make a nice
strawman for you, which is I suppose why you continue to cling to it.

None of this matters. It doesn't matter if the crystalline base rock is
metamorphic or whatever. The question is, why is the overriding
sedimenatary skin still there? According to Searle, this "skin" that
used to overly the Ordovician that currently tops Mt. Everest was only
6 km thick. It has not had a complicated history of multiple burials
and exposures. It has been uplifted as an erosional surface,
supposedly, for some 60 million years. Beyond this, according to
Harutaka Sakai, Mt. Everest was about 15,000 meters tall some 20
million years ago just before about half of it slid off at this time,
exposing the Ordovician sediments that currently top Mt. Everest - or
at least close to it.

Sean Pitman
www.DetectingDesign.com

.

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