Department of Physics and Astronomy
University of Alabama
Tuscaloosa, Alabama
The New River Mine is a
surface mine which was spotted by Jim Lacefield in early February
this year, and shortly thereafter Jim and I scouted the site out. As
expected, the site included plant fossils, but one difference compared
to other sites that Jim noticed was an abundance of fossils of
Artisia, the pith of the gymnospermous tree known as Cordaites. The
only other sites where I have seen Artisia fossils are the Kimberly
surface mine (see
BPS report for May 29, 1999), and another mine near
Eldridge that the BPS visited with Wayne Canis's class in March
1998.
Figure 2 View of a rock wall roughly on the east side of the site. |
Bruce Relihan was the first to find an interesting specimen of Artisia, shown in the picture here. Artisia is characterized by horizontal ridges along the pith, which can be found in cast form as well as impressions, much like a Calamites pith. The specimen Bruce found appears to be either an impression or a highly flattened cast. The ridged area is framed by a larger area obviously affected by the plant. This frame must indicate the true extent of the trunk. |
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Figure 3 Artisia specimen found by Bruce Relihan. |
Other types of fossils found were bark impressions of arborescent lycopods. I show pictures of two different types here. One appears to be of the type Lepidodendron obovatum, with very large leaf scars. I am not certain about the type of the other piece shown, other than it is also likely to be a Lepidodendron. |
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Figure 4 Bark impression of Lepidodendron obovatum, with large, distinct leaf scars. |
Figure 5 Bark impression of another likely type of Lepidodendron. |
The last pieces I illustrate are ones I found in February during my scouting visit with Jim Lacefield. One appears to be a mostly unflattened cast of a branch of Calamites. The piece shows 15 strong, indented nodes, and I must say it resembles a petrified tootsie roll! I am not sure of the species of this Calamites, but I did find a type of Calamites at this site that I was able to identify. I found highly compressed cast pieces of what I think is Calamites suckowi, one of the more common species of this genus. |
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Figure 6 Cast fossil of a branch of Calamites, with 15 clear nodes. |
After a couple of hours of searching with limited results,
trip
attendees decided to return to Union Chapel Mine, about 30 miles east
of the New River site. Union Chapel Mine is so rich that it continues
to yield good specimens even though many people have visited the site
the past 4 months. It is a good site to fall back on when other sites
do not live up to expectations. See the reports for January 23, March
19, and May 28, 2000 for information on this mine.
Department of Physics and Astronomy
University of Alabama
Tuscaloosa, Alabama
The field trip on March 27,
1999 was the second
organized BPS trip to a construction site near Warrior. The
trip was attended by about 25 people, mainly from Birmingham,
Huntsville, Tuscaloosa, the Florence area, and the University of North
Alabama. Attendees included BPS members, guests, children, professors,
and students, and the day was sunny, clear, and warm.
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Fossil hunters at the main rock pile where Lepidodendron and Sigillaria specimens were abundant. |
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The site was
first
identified as being a source
of Carboniferous-period plant fossils by BPS member Gerry Badger, and
the first BPS field trip to the site took place on November 15, 1997.
Although various BPS members and probably others have visited the site
at various times during the past year, the site has changed so much
that on March 27, the site was better than it had ever been before as
far as numbers and quality of plant fossils are concerned.
The most abundant plant
fossils found during
our most recent visit were bark impressions of the giant arborescent
lycopods Lepidodendron and Sigillaria. These were mainly found in rock
piles around the area of a northeast wall of rock. Large slabs showed
the familiar Lepidodendron leaf scars, which look like fish scales. In
many cases the scars were clear and well-defined, making the specimens
extremely beautiful examples. On close inspection, the leaf scars show
characteristic bundle and parichnos scars representing leaf attachment
points, and many of the pieces are probably of the same species.
However, after checking various books I have not yet identified the
exact species at Warrior. It is clear also that more than one species
of Lepidodendron is present at this site. It is also interesting that
specimens of Lepidodendron at Warrior came in both direct and inverse
impressions. In direct impressions, the leaf scars are raised, and are
more like molds of the original object. In most pieces, however, the
leaf scars are simply inverse impressions of the original raised scars,
and therefore appear as depressions in the fossil.
The |
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Also abundant at this site,
but not necessarily
found in the rock piles, were several types of seed ferns
characteristic of the period. These were found at a specific level of
the east rock wall less than a foot above the ground level and about 20
feet from the rock piles. The ferns found included beautiful examples
of Eusphenopteris, Mariopteris, Neuropteris, and Alethopteris form
genera, but I have not yet determined exact species. Because many of
these were found in situ, they were still beautifully preserved with
dark carbonaceous remains of the original plant material and fine
details of vein systems in individual pinnules. Several attendees spent
much of their time searching for ferns at the rock wall, and many were
found. According to Dave Kopaska-Merkel, one young person, whose first
name was Jonathan, split a large slab and found some very nice large
ferns inside. Although I am not aware of any examples found during this
trip, the site also is known for having Lyginopteris ferns which are
distinctly different from the others. Several different species of
Sphenopteris ferns have also been found in the past.
View of rock wall on east side of site where ferns were found in situ. |
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Typical example of a set of ferns extracted from the above part of the wall. |
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Fossils
of the well-known
horsetail, Calamites,
have also been found in abundance at this site. Several attendees
(including myself) found three-dimensional Calamites stems further down
the same rock wall where the ferns were found. Dave Kopaska-Merkel
found a nearly foot-long Calamites specimen embedded in a larger rock.
Also found were excellent specimens of the foliage of Calamites,
including a fine small piece of (probable) Asterophyllites
equisetiformis shown to me by Gerry Badger. At least three different
species of Asterophyllites have been found at this site.
There
was
In summary, this field trip |
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Group working on Stigmaria fossil near road to upper level of site. |
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