From: Bill Payne (bpayne15@juno.com)
Date: Thu Mar 27 2003 - 21:45:48 EST
On Thu, 27 Mar 2003 17:16:02 -0500 "bivalve"
<bivalve@mail.davidson.alumlink.com> writes:
> But your reference gives no evidence that it was a high energy
> environment in which the 10-15 cm of diatoms were deposited. On the
> contrary, it suggests that these were deposited on the beach
> ("formed on the Oregon coast"), where the flow consistently goes to
> zero. Like Michael, I had missed your intended point from the quote
> and thought you were citing it as evidence of high depositional
> rates.
It looks like we all see what we want to see. I have re-copied from my
original post and put the references to high-energy environments in blue:
"Tidal channels lined with coral rubble between the Florida Keys have
been oberved to accumulate a much as 10 cm of lime mud during such
events, in spite of the fact that these are areas of high energy where
normally only rubble and sand accumulate." "Deposits of lime mud as
thick as 20 cm and abundant lime mud intraclasts are interbedded with
ooid and in a tidal channel in the Exuma Islands (Dill and Steinen 1988),
where tidal currents as high as 100 cm/sec occur daily (Dill et al.
1986)." (from Whitings, A Sedimentologic Dilemma, by Shinn et al,
Journal of Sed Pet, v 59, no 1, Jan 1989, p159)
Just because the velocity may momentarialy go to zero on a beach is not
rational support, as far as I can envision, for rapid accumulation in
otherwise high-energy environments of very fine-grained sediment.
"Geologists often assume that the accumulation of thick layers of tiny
microscopic organisms such as the White Cliffs of Dover in England
required lengthy periods of time. But such accumulation can occur
rapidly. Along the coast of Oregon a three-day storm of high winds and
rain deposited 10-15 cm of microscopic diatoms for a distance of 32 km.
[Campbell, AS. 1954. Radiolaria. In: Moore RC, eidtor. Treatise of
invertebrate paleontology, Part D (Protista 3). NY: Geol. Soc of Amer.,
and Lawrence, Kans.: Univ of Kansas Press, p. D17.] I have seen a
well-preserved fossil bird and many fish in thick beds of microscopic
diatoms near Lompoc, California. A whale was also found in this deposit.
Such preservation would require rapid burial before disarticulation of
the organism would occur. Evidently microscopic organisms can be
deposited rapidly." (_Origins, Linking Science and Scripture_, Ariel
Roth, p 201)
Here again, a 3-day storm deposited microscopic particles. The last
quote is, as you said, evidence for rapid deposition of microscopic
particles.
>
> Having no experience with the particular beds around the Grand
> Canyon that you are citing on paraconformities, I do not know what
> the conventional explanations are in those specific cases. However,
> all my experience in geology has consistently confirmed that
> conventional geologic views are a better match for physical reality
> than young-earth ones, so I am not strongly motivated to look this
> up. You should be able to find helpful references, e.g on Georef,
> if you want an answer.
I wouldn't want to deprive Michael of the pleasure.
> I have seen a relatively flat contact
> between upper Cretaceous and Pliocene strata that had a trace of
> middle Eocene at the contact. Flat layers had been deposited and
> eroded, more flat layers were deposited and eroded, etc. with the
> end result of an unspectacular unconformity representing nearly 70
> million years.
How do you know what was deposited and eroded if the "deposited" strata
are now gone? Why do you assume strata were "deposited and eroded"?
What evidence do you have for this assertion?
> The color contrast between the Cretaceous and
> Pliocene deposits makes the change obvious, but the relief of the
> contact was very low. Homogenous flat layers should erode
> relatively eve!
> nly.
What is your modern analog? I would think homogenous flat layers would
be cut by river channels. Are you saying that the erosion was due to
sheet flow (as in a Flood)?
Bill
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