From: Bill Payne (bpayne15@juno.com)
Date: Sun Aug 25 2002 - 01:56:17 EDT
On Thu, 15 Aug 2002 13:43:13 -0500 James Mahaffy <mahaffy@mtcnet.net>
writes:
> I don't really have time to do a lot. I do like the way you
> respond. You did better than I thought you could, but it is still to
> broad and I think fails when you try and apply the model to the
> specifics.
Thanks for your response James, but you managed not to answer the
specifics of my questions. Maybe you just didn't have time, so I'll
repeat them, and some others follow:
Question 1 - Regardless of how this parting was formed (aeolian or
aquatic), it
captures the topography of the top of the organic surface at the moment
of deposition. If this was a swamp, where are all of the vertical trees
that were supposedly growing in the swamp? If there had been trees
growing in the swamp, they would have been preserved (at least the base
of the trunks) in the partings. The absence of the trunks in the blue
band and other partings is evidence [or at least could be interpreted]
that this was not a swamp in the first place. So James, how do you
explain the lack of trees in the swamp
model?
Question 2 - As I recall, the black shale Austin showed us has occasional
pyritized marine fossils. Steve envisioned the black shale as being
deeper-water deposition, with the organic fines settling out last. I'm
not sure where he said the gray shale material came from, but it graded
into black shale as the fine organics settled.
How do you explain this coal-gray shale-black shale sequence within the
swamp model?
Question 3 - I would expect debris to be thicker in the lows. However, I
have seen
coal of a consistent thickness draped over what appeared to be a
contemporaneous slope. How do you explain that with your swamp model,
James? Let me give you a specific example to explain.
In A. T. Cross' "The Geology of the Pittsburg Coal" (Cross, 1952) on p
47, Figure 6 shows a sandstone lens in the upper part of the seam. On p
49 is a photograph of the upper split of coal over the sandstone lens.
The text says: "The roof coal is three feet thick and to the left the
upper 12 inches is seen to split off and pass over a sand lens, which at
its thickest is about 10 feet. The upper split can be traced for about
100 yards where it can be seen to rejoin the main roof coal below."
How does this fit in the swamp model? The 12-inch split sits on an angle
of about 20 degrees where it ramps up on the sand lens. How did the
swamp not deposit more coal around the 10-foot sand lens than it did on
the sides and top of the lens?
> Not bad (I really am impressed by the attempt), but still flawed -
> perhaps fatally. IF your model is right then it would appear as a down
> cutting channel. While they do exist this one ws not. You need to
have
> your turbidity current to be present while the vegetation mat is being
> deposited. You also need to explain why the Herrin coal thickens to
> about 6-8 feet on the flanks of the channel while more distantly it is
> much thinner (about 4 feet). The data on this is excellent (ISGS coal
> section mapping).
>
> Also would a turbidity current cut down through coal. It is fairly
> resistent?
OK. Then why not have the turbidity current pulsing while the mat is
settling? The organics which would have settled in the channel may have
been pushed off to either side, making the coal thicker near the channel.
I really don't understand the topography here though. Were the flanks of
the channel where the Herrin is thicker actually 2 to 4 feet higher (or 6
to 20 feet before compression of 3 to 5x) than the top of the Herrin? Or
was the bottom sloped and the surface below the blue band horizontal? Is
the blue band thickness consistent across the flanks?
> > > And then there are the nasty problems like how do you explain
> > > biostratigraphy to work with your model in the numerous coals in
the
> > > Illinois Basin (Peppers, 1964 and 1970). Some miospores are only
found
> > > in certain coals and their ranges can and are used for the
> > > biostratigraphy of the coal. That for me was one of the main
reasons
> > > why I find the flood model just unusable.
Here in Alabama, we have some coals which are sitting flat on
cross-bedded sandstone and shale, with none of the "paleosol" features.
This area is northwest of Jasper near Carbon Hill, and even Jack Pashin
of the AL Geological Survey says these coals are transported. Other than
the lack of a paleosol, they look just like other banded coals to me.
Have any biostratigraphic studies of miospores been done on obviously
transported coals? If so, I would like to have the references, please.
> Your model forces you to something like this but often it is not the
> dominant spore that differs and I would think with different vegetation
> mats you would be more apt to get a lot of spores out of place and not
> found only lower or higher in the coal section.
That's what you think, but do you have any data to back this up? Have
you studied obviously transported coals and shown that the spores are
more mixed up?
> > A) General lack of stigmarian axial root systems beneath the coal
> seams;
>
> This is just not true. Yes historically at one time this was thought
to
> be true and is still true of some coals or in some places. But their
> are clearly many that do have Stigmaria rootlets in the underclay.
When
> I was at the University of Illinois I glanced at all the MS and Ph.D.
> theses and a number dealt with this problem. The lack of roots in many
> places may still be something not easily explained but it in a number
of
> places their are rootlets penetrating the underclay. Bear in mind too
> that lycopod roots are different than angiosperm roots so they may have
> had difficulty penetrating some harder substrate. However they do a
good
> job of penetrating rotting vegetation as is clearly demonstrated in
> preserved peat in coal balls where the vegetation where stems are often
> full of rootlets that have grown into them.
You may be missing an important point here. I said "stigmarian axial
root systems", and you responded with "rootlets". I have seen rootlets -
apparently not associated with an axial root system, and the rootlets are
usually all crinkled up, not straight as when I have seen them attached
to an axial root. Crinkled rootlets are not what I would expect from
trees with trunks several feet in diameter. These rootlets appear (to
me) to have been transported and crinkled during burial/compression.
How do you explain the general absence of _axial root systems_? And the
absence of any roots at all beneath some coals (as you mentioned above)?
> > B) General lack of either tree stumps or roots in partings;
>
> In at least the "Blue Band" Not sure it is generally true.
OK. Let's start with the blue band. Why no stumps from below or roots
from above in the blue band?
> > C) General lack of vertical tree stumps/trunks in the sediment
overlying
> > coal seams;
>
> Too broad a statement. I brought back a big stump from a coal
(probably
> the Black Oak coal) near Pella. It was sitting right on top of the
> seam. There was a second one (obviously sigillaria) that also appeared
> to be sitting on the top of the coal and extending perhaps 20 feet up
> into the siltstone. I also believe both Bill DiMichele and Aureal
Cross
> describe areas of coal seams where there are numerous upright casts
> right at the top of the coal.
>
> Remember in underground mines you would never see them.
Oh yes you do too, and the miners call them "kettles" or "pots". They
are dangerous because they can break loose from the roof of an
underground mine and mess up your whole day.
If you have seen Steve Austin's "Mt. St. Helens" video, then you know
that a vertical trunk does not an in situ tree make. Many transported
trees float vertically because the root end soaks up more water and they
settle out standing vertical on the bottom. If you read the unpulished
paper I sent to you, then you saw a case for transported vertical trees.
What evidence do you have that these trunks you refer to are in situ?
Just because they were sitting on top of a coal does not make them in
situ.
> > D) General lack of change in total coal seam thickness between areas
> > containing splits and those that contain no splits;
>
> Not true at all of the Herrin. It is much thicker in the vicinity of
the
> Washville channel.
You win that one. :-)
> > E) Commonly extensive, continuous nature of thin partings;
>
> Grant you that one.
Whoa there. Please explain within the swamp model how this can be.
> > F) Generally consistent thickness of coal seams draped over
> > contemporaneous slopes.
>
> Only is some cases. Some coals in Illinois are widespread and fairly
> universal in their thickness but there are others that are restricted
to
> topography. Only deposited in lows. The assumption is that the
> widespread coals were deposited on a flat floodplain. In other words
> sediments deposited before the coal flattened the topography. But I
> would have to refresh myself on the specific stratigraphy before I went
> further.
How is it that "coal flattened the topography"? And within the swamp
model, how do you explain a constant thickness of some coals over hills?
I appreciate the time you are taking here James. However, before you can
say the allochthonous (transported) model is fatally flawed, I think you
need to address the issues I have raised here.
Bill
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