Re: Roots in coal?

From: Kevin and Birgit Sharman <ksharman@pris.bc.ca>
Date: Fri Jan 09 2004 - 11:14:28 EST

----- Original Message -----
From: "Bill Payne" <bpayne15@juno.com>
To: <ksharman@pris.bc.ca>
Cc: <asa@calvin.edu>
Sent: Saturday, January 03, 2004 6:57 AM
Subject: Re: Roots in coal?

  This is why I say I don't see how we can get banded
> coals from this structureless mass of peat. Does your model include
> transformation of structureless, intensely root-penetrated peat into
> banded coal? I think you said the structure of cells may be lost during
> coalification, but the formation of bands from a root mat seems to
> require some fundamental reorganization

  Are you saying that
> this tangled mass of roots could become banded coal through
> coalification? If so, this is the process I need to understand.

Bill, here is a paper by Cohen and Bailey (1997) on artificial coalification
of peat. Quotes from the abstract:

"Petrographic changes during coalification of three peat samples were
investigated by artificial coalification experiments using a semi-open
reactor system. Compressions of from 83 to 88% produced dark brown to black,
shiny, flattened pellets exhibiting microscopic banding......The planar,
root-dominated, Rhizophora facies showed the greatest change in microbanding
character during coalification; in that, the numerous lens-like bands
produced by the compressed roots were very distinct at the 60/2100 psi
(121.4 kg/cm2) stage but nearly disappeared at the 175/5000 psi (289.1
kg/cm2)) stage. This is explained as a result of differences in rates of
coalification of the different telinitic precursors in the roots
(multilinear vitrinization) and could explain why roots are significant
components of many modern peats (and ancient coal ball concretions) but are
difficult to recognize in bituminous coals......The above petrographic
results, along with previously reported chemical results, all suggest that
the methods that we have used in these experiments have produced changes
that might reasonably be expected to occur during natural coalification
(despite the fact that we have speeded up the process)."

Does this, along with my previous comments, explain it well enough? You
have expressed skepticism that roots in modern peats can transform into
banded coal. Just because you can't conceive of how this could happen
doesn't mean it can't happen (argument from incredulity).

Kevin

Arthur D. Cohen, Alan M. Bailey (1997) Petrographic changes induced by
artificial coalification of peat: comparison of two planar facies
(Rhizophora and Cladium) from the Everglades-mangrove complex of Florida and
a domed facies (Cyrilla) from the Okefenokee Swamp of Georgia. International
Journal of Coal Geology, v. 34, issues 3-4, p. 163-194.
Received on Fri Jan 9 11:15:23 2004

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