That sure sounds wonderful but is a generalization that does not address
the specific sitution. Just one example: What of the tephra layers that
are so clearly identifiable in the sediment cores. During rapid
sedimentation how did such distinct tephra layers get deposited. The 70 cm
tephra at 21 meters contained a good bit of pollen itself of which the vast
majority was Carpinus pollen. Carpinus (hornbeam - Betulaceae) is a spring
flowering understory tree/shrub that would have carpeted the forest floor.
It would seem reasonable to suggest that the ash fell at a time in the
early spring when Carpinus and oaks which flower before the leaves appear
and thus before many other taxa released their pollen. Why these pollen
types to the exclusion of other pollen types if all of this is still in a
flood environment?? In additon, above the tephra are high amounts of grass
pollen followed by pine pollen and then oak. This is what one would expect
if we had succession following the destruction of a forest by ash.
BTW please don't feel that I would be upset if you read the original
papers. There was a reason for providing references.
>On Mon, 3 Nov 1997, David Campbell wrote:
>> >If one were to core the lake and pond sediments, one would find a
>> >surprising stratification of a variety of pollen zones.
>> Has this been done? I doubt that stratification is good enough to resolve
>> changes on such a fine temporal scale-bioturbation mixes things very
>Bioturbation may well be a problem today, however, in a multi-event
>Flood catastrophe, bioturbation would be unlikely to occure because of
>the quick succession of burial of each layer. We find multiple layers of
>sediments which reveal no bioturbation, but if today is the sample of the
>past we should find multiple lyares of sediments fully bioturbated.
I might be wrong but it seems that nearly all the ODP (Ocean drilling
project) papers I have looked all refer to portions of cores which exhibit
evidences of bioturbation and so exclude any botanical and
paleoclimatological intepretation in many cases.
Joel and Dawn Duff / | ' \ Spell Check?
Carbondale IL 62901 ( ) 0
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