Hi Bill
So you are now a southern Baptist?
Bill Payne wrote:
> On Thu, 07 Jun 2001 20:45:01 +1000 Jonathan Clarke
> <jdac@alphalink.com.au> writes:
>
> When I discussed this w/ Glenn several years ago on the ACG, Glenn tried
> to say that these were treeless bogs covered with grass, until he
> realized that grass didn't evolve until the Cretaceous. According to
> James, the "ancient ones" were different in that the majority of the coal
> consists of tree parts. Gastaldo has documented tree trunks vertically
> over the Mary Lee coal seam. I have seen tree trunks above, below, and
> between coal seams. I think your straw man allegation is a bunch of
> feathers. :-)
Please stick to the point. Your said (Thu, 07 Jun 2001 20:45:01 +1000) "
tree stumps commonly up to 2+ feet in diameter are virtually *never* found in
coal seams in the eastern US". I gave you five references, two from the
eastern US and three from Canada that give examples of just this. Have you
read them? You now write "I have seen tree trunks above, below, and between
coal seams." So you recognise that there are erect I am not surprised you
have seen trees above, below, and between coal seams. The references I
mention give examples of this. Your point is???
>
> > Secondly trees are reported growing from the tops of at least some coals
> in the eastern US. See T. Demko and R. A. Gastaldo "Paludal environments of
> the Mary Lee coal zone, Pottsville Formation, Alabama: stacked clastic
> swamps and mires" (International Journal of Coal Geology 20 (1992): 23-47)
> figure 3 (sketch) and figure 6 (generalised diagram); R. A. Gastaldo
> "Implications on the paleoecology of autochthonous lycopods in clastic
> sedimentaryenvironments of the > Early Pennsylvanian of Alabama"
> (Palaeogeography, Palaeoclimatology, Palaeoecology 53(1986): 191-212)
> figure 1 (generalised architecture) and figure 3 (wall > map). For non-US
> examples (and to show these are not just figments of the imagination of the
> dreaded Gastaldo) see J. W. Dawson "On the coal-measures of the south
> Joggins, Nova Scotia" (Quarterly Journal of
> the Geological Society of London 10 (1854): 1-41) figures 2, 5 and 8 (all
> field sketches); J. H. Calder, M. R. Gibling, C. F. Eble, A. C. Scott,
> and D. J. MacNeil "The Westphalian D fossil
> lepidodendrid forest at Table Head, Sydney Basin, Nova Scotia:
> sedimentology, paleoecology
> and floral response to changing edaphic conditions" (International Journal
> of Coal Geology 31(1996): 277-313) figures 2 & 3 (stratigraphic logs)
> figure 4 (long section), figures 6a & 7b (photographs). What was that
> about being weary of people criticizing ideas but refusing to address the
> data?
>
> Ah, my friend, you are much too ready to accept the opinions of others
> (you should believe me and no one else :-)). A year or so ago I saw a
> Powerpoint presentation of a study by a geologist (OEC) and a friend of
> his (professor in the field of humanities who did the presentation) on
> the Blue Creek/Mary Lee stratigraphic section. The Blue Creek coal
> underlies the Mary Lee and in this mine (Cedrum Mine in Walker County,
> Alabama); they are separated by about 20 feet of shale and/or sandstone.
I give you five published references easily located at a good library and you
mention a your interpretation of powerpoint presentation by unnamed people?
>
>
> The presenter showed photographs of, I'm guessing, more than 50 vertical
> tree trunks in the interval between the Blue Creek and Mary Lee. *None*
> of these trees had roots attached. One photograph in particular was a
> closeup of the base of a tree, and clearly showed that the trunk was
> truncated, not rooted.
Is this your interpretation of the photos or are they the presenter's? Are
the bases of the trees truncated or is presevation such that small structures
like roots are not likely to be preserved? But what is your point exactly?
>
>
> This is the same area and the same Mary Lee interval that Gastaldo
> interpreted as "stacked clastic swamps." I have an abstract which I
> guess is for the article you referenced above. I didn't realize he had
> authored an article; thanks for the references - I'll try to get them.
> You mentioned "figure 3 (sketch) and figure 6 (generalised diagram)."
> Did Bob publish any photographs or only sketches?
Timothy Demko's paper (he is the lead author, not Gastaldo and the work is
based on his Master's thesis) has 8 figures. Figure 1 locality map. Figure
2 stratigraphic section. Figure 3 sketch showing architecture of plant
fossil horizons. Figure 4 photographs of erect trunks (a) loycopod
terminating in Mary Lee coal, (b) erect Calamites above Blue Creek coal
(paper is not clear whether it is some distance above the coal or whether
base actually rests on or in the coal). Figure 5 photographs of leaf litters
from Blue Creek -Mary Lee interval, (a) pteridospherm aerial debris, (b)
prostrate log, (c) sections of siderite replaced log. Figure 6 generalised
lithologic logs showing the two different types of palaeosols in the Blue
Creek-Mary Lee interval. Figure 7 isopach map of Blue Creek coal. Figure 8
Model for alternation of stacked clastic swamp paleosols peat accumulations.
>
>
> > Thirdly, as you should well know, layering in coals can have many
> origins. You have to be specific. I think we have discussed here and on
> the ACG
> list compaction, sediment seams, formed by flooding of swamps, and ash
> falls. Unless you have something new to add I don't see much point
> discussing
> them.
>
> "Sediment seams, formed by flooding of swamps, and ash falls" *prove*
> what I am saying. If these were swamps, and if these swamps had trees
> growing in them, them the sediment seams and ash layers (partings) in
> coal seams would be interrupted by the trunks of the standing trees.
> James, I know you don't accept my interpretation, but will you please
> help me out here and confirm the continuity of the partings?
We discussed this on the ACG list. Flooding of the swamps does not prove your
theory at all. Episodic flooding of coal forming environments is a integral
part of most of the various models proposed (delta crevasse splay, flood
plain, intramontane basin coastal plain). Tonsteins vary greatly in extent,
depending on the deposit. Where they are continuous there was clearly nothing
to interrupt this continuity, whether that continuity is of the order of 10's
of m, km, or 10's of km. So what?
Jon
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