Bill you said:
"Furthermore, had the coal bed come from an organic bed accumulating in
a
swamp, then the thin bedding evident in banded coals would have been
destroyed by the bioturbation of rooting by the trees in the swamp.
"Trees in the mixed peat-swamp forest and pole forest have spreading,
buttressed, and prop roots, which are generally confined to a root mat
50-80 cm thick at the top of the peat and do not penetrate to the deeper
peat or mineral sediments below the thick peat. If the peat beds of
Indonesia were to become coal, they would not look like the banded coals
of the eastern US. The 50 to 80 cm thick root mat would have destroyed
all thin-bedded structure that we observe in banded coal seams."
Do remember though that most of the Carboniferous coals were dominated
by lycopods and most of the trunk was "bark". Those are plants quite
different than the angiosperm trees coalified in Inonesia swamps. This
difference could mean that Carboniferous coals are easier to flatten.
But I am not sure that Carboniferous coal dominated by gymnosperms
(Cordaites) is any less banded. You are right that it is not easy to
account for the uniform widespread thickness and sharp contact of some
of the widespread partings (I have studied one of the more famous of
these, the "blue band" in the Herrin Coal of the Illinois Basin). And
then I wonder if the Western Cretaceous coals generally have less of a
sharp contact? That is true of a small coal in the Dakota fm here south
of Sioux City but I haven't looked at many of them. In your model they
too should be floating vegetation mats. Bill remember all models have
some problems. While coal researchers are not going to quickly change
to a paradigm of floating vegetation, if they tried, I think they would
find more problems with this model. For one it is much harder to
explain intraseam variation in plant material or spores [my area] and
from one coal bed to another (biostratigraphy really works on those
coals in the Illinois Basin). And of course Bill, if you want to
persuade the scientific world you need to find a respected coal
petrologists to think your model works. If I remember right Steve
Austin did some petrology on the coal he studied for his Ph.D., but he
didn't continue this and is NOT respected in the area for his petrology
(he just hasn't published much in the area since then). Petrologists
spend their lives looking at slides of thin sections of coal.
But I have a Zoology test to finish before 8AM so I probably should not
have taken this break.
Keep up the reading on coal literature Bill.
-- James and Florence Mahaffy 712 722-0381 (Home) 227 S. Main St. 712 722-6279 (Office) Sioux Center, IA 51250
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