>Yes, everyone is convinced. Have you read
>
>CROSS-IDENTIFICATION OF RING SIGNATURES IN EOCENE TREES (SEQUOIA-MAGNIFICA)
>FROM THE SPECIMEN RIDGE LOCALITY OF THE YELLOWSTONE FOSSIL FORESTS
>
>AMMONS R, FRITZ WJ, AMMONS RB, AMMONS A
>PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
>60: (1-2) 97-108 JUL 1987
Hmmm, looks like the case wasn't as closed as you thought in 1984. At
least Fritz and Ammons'es have continued working on it. When you are
trying to test whether there is a match between trees in different layers,
finding trees that match in the same layer is not a very good criterion for
establishing your hypothesis. And no, their 60 ring match is orders of
magnitude less certain than Arct's analysis, in which not only do the ring
sizes match one for one, but the earlywood rings match and the multiple
latewood rings match as well. And Fritz' work says nothing to the
possibility that the trees were all growing somewhere else and brought in
by the same kind of forces that were effecting the same kind of process in
spirit lake. Those papers looked pretty weak to me.
>And from the first page:
>"All workers agree that most of the layers of petrified trees on Specimen
>Ridge, an area representing deposition in lower-energy lowland facies, are
>most likely preserved in place"
Since most of the work on the forests was done by myself and my students
for a period of 15 years, and by Coffin and others who do not agree, I
don't know what his reference is based upon. He was a student of my
student Lanny Fisk, who also certainly doesn't agree, unless he too has
changed his position. Here is one worker that does not agree.
>They found a 60-year signature pattern that they found in the 15-25m level,
>but they only tested it on like three trees (which were clearly buried
>in situ).
I can tell you that there is no such thing as "Clearly buried in situ" in
the yellowstone forests. What kind of criteria would you apply? The trees
look superficially like they grew there, but all of the other features of a
"forest" are sadly lacking. Roots? All over the place, just as is the case
for the trees transported by the lahars at Mt. St. Helens.
>Collinson discusses the Yellowstone Specimen Ridge site on p.56-58 as
>during a discussion of community reconstructions of ecology in the Eocene
>as follows:
>
> The petrified forests of Yellowstone National Park, USA, have long been
>regarded as examples of Eocene forests preserved in situ (Dorf, 1964).
>Numerous levels containing upright tree stumps can be observed in an
>exposure at Specimen Ridge. However, following the recent eruption of
>Mount Saint Helens many observations were made concerning tree stump and
>trunk depsition in comparable modern volcanogenic sediments (e.g. Fritz,
>1980; Fritz, 1983; Fritz and Harrison, 1985). These showed that upright
>tree stumps could be transported and re-deposited so as to appear as if
>they had been buried in situ. A palaeoecological analysis of the woods and
>pollen from the sediments at Yellowstone (Chadwick and Yamamote, 1984)
>emphasized earlier observations of "mixed" floras in single levels. Growth
>ring evidence and leaf and pollen floras all implied that mixtures of
>tropical and temperate plants existed at individual stratigraphic horizons
>(see also Fritz, 1981). These factors seemed to support suggestions that
>the "fossil forests" were not perserved in situ. Retallack (1981) and
>Yuretich (1984) responded to these observations by demonstrating that some
>stumps were unquestionably in place as shown by fine roots embedded in
>fine grained sediments below conglomerates which flowed around the trunk
>bases. Furthermore, well-differentiated soil profiles were developed at
>these horizons.
There are lots of roots and rootlets. There are large roots that end
abruptly in a fracture, but otherwise appear to be eminating from upright
trees. There are roots attached to upight trees that are fractured and
broken in the layer below the tree. That well differentiated "soil
profile" in thin section reveals perfect preservation of the organic level
materials, with graded beds of ash underneath the profiles of broadleaves.
Try doing that in a soil. I have examined over 100 thin sections of the
organic horizons, and never have I seen anything like a soil or a soil
profile.
>
>The consensus by people involved seems to be that while most of the
>levels represent in situ-buried trees which grew contemporaneously
>and form "fossilized forests," there is also transported material present
>as well, which I'm not sure anyone has figured out where it came from.
I thought the work on the forests was pretty well finished and moved on to
other areas 10 years ago. If you have read my paper on the paleoecology,
you will see what proponents of in situ growth are up against. I would
agree that there is no good easy explanation for all the features of the
deposits. Suffice to say that viewing them as successive forests as Dorf
did was hopelessly simplistic. There is geochemical data available now that
will shut the door on the in situ interpretations of the Yellowstone trees.
I guess I will start urging its publication.
Art
http://chadwicka.swau.edu