>I don't think this guy, whoever he is, knows what he is talking about<
Actually, the problem was a failure to make sure that my audience
knew what I was talking about. I was cited anonomously because I had
replied off-list.
Obviously, I was not very clear in my initial reply. A large meteor
impact can produce earthquakes, but not ones that will produce the
motion necessary for the model Mike seems to be envisioning. A large
impact will leave evidence such as a crater, unusual isotopes,
tektites, and killing local organisms. At best, a region that was
already precariously poised (e.g., the south end of Hawaii today or
the edge of the continental shelf around the Gulf of Mexico at the
end of the Cretaceous) could have been triggered to fall by a large
enough impact, but the magnitude of such an impact must be compared
with the magnitude that would have destroyed the ark. However, there
is no evidence that such a situation existed near the Persian Gulf a
few thousand years ago. Earthquakes in tectonically active settings
can produce abrupt rising or lowering of a region (e.g., Chile, with
the series of terraces observed by Darwin), but I know of no example
of lowering and raising of the same !
region following each other so quickly. Over the past 2000 years,
the vicinity of Naples has gradually moved up and down, but that will
not drown anyone. Theoretically, I suppose that it is possible to
have a region drop over 20 feet and come back up about a year later,
but I know of no reason to support the idea that it happened in the
Persian Gulf region at the time needed by this model.
A second impact will not reverse the effects of the first one.
Compressional tectonics is the only cause I know of for rapid
elevation of a region.
Dropping a large region of land into the ocean will produce large
waves, unlikely to have a desirable effect on the ark (e.g., turning
upside down; washing it either miles inland or out to sea).
Dr. David Campbell
Old Seashells
University of Alabama
Biodiversity & Systematics
Dept. Biological Sciences
Box 870345
Tuscaloosa, AL 35487 USA
bivalve@mail.davidson.alumlink.com
That is Uncle Joe, taken in the masonic regalia of a Grand Exalted
Periwinkle of the Mystic Order of Whelks-P.G. Wodehouse, Romance at
Droitgate Spa
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