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Re: AMPHIBIOUS MOSASAURS?
In a message dated 99-03-03 09:14:50 EST, you write:
Shale (mudstone or any other variant) is nothing more than an
agglomeration of clay-sized particles of clay minerals (phyllosilicates).
True, black shales are generally bear a certain percentage of organic
residue. But only a very small amount (less than 1%) is required to turn a
shale black (see any petrology textbook authored by Harvey Blatt). A qual.
scheme of the Pierre Shale might look some like - 97% clay minerals, 1%
silicate minerals, 1% calcareous nannofossils, and 1% organic hydrocarbon.
Truly "organic-rich" shales are sometimes referred to as oil-shale,
and contain perhaps 3-4% hydrocarbon.
There is absolutely no evidence of which I am aware to support the
notion of a kelp choked seaway.
This is a reply I received from a friend deeply involved in seaway studies.
I hope it's informative. Dan Varner.