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Date: | Mon, 13 Jul 2009 16:35:58 -0500 |
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I wish to extend my thanks to both Marc and Erich for the explanations of
possible causes of vertical columns within sedimentation layers. Geology is
one area that I have never had the opportunity to study. So these
explanations are particularly helpful to me.
Dr Harrub led into this subject matter with a picture of Spirit Lake after
the Mount St. Helens eruption. There were a lot of logs (trees stripped of
their branches) floating in the lake. He claimed that as these trees became
waterlogged and eventually sunk, they did so in an upright position and
remained upright as they settled on the bottom. Since trunks do not last
very long, the sedimentation surrounding the trees could not be millions of
years old. According to him, that proved his claim that all sedimentation
layers are the same age.
Jack Cannon
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