Arthrophycus
Sunday, August 26, 2007
Friday, October 13, 2006
Tuesday, October 10, 2006
Final stop of the New York State Geological Association field trip B3: North Evans / Genundawa. This locality is an overpass on Route 20 near Bethany Center. Professor Gordon Baird, SUNY Fredonia explains the stratigraphy. Dr. Bill Kirchgasser, SUNY Potsdam is on the left and Dr. Kym Pocius, Rochester Academy of Science Fossil Section, looks on from the right. The top section is the Genundawa Limestone and the black shale beneath is the Penn Yan. One layer within the Genundawa contains numerous steinkerns of the goniates ammonoid, Koenenites. We collected some of these from blocks off the Route 20 northside berm a few hundred yards to the east of here.
Monday, October 09, 2006
NYSGA 2006 Field Trip B3, stop 3 at an unnamed tributary of Cayuga Creek. This trip explored the end of the Hamilton Group and the start of the Taghanic wierdness that leads to unconformities, time-compressed lag deposits (two million years represented in a couple of inches of rock) and nearly anoxic black shales. Professor Gordon Baird, SUNY Fredonia, pulls out a block of Penn Yan shale looking for a styolinid layer called the "Linden Bed." Professor Bill Kirchgasser, SUNY Potsdam, loupe at the ready, may have found it. Professor Andrew Bush, University of Connecticut, gets his stratigraphic bearings.
On the NYSGA 2006 B3 field trip, geologists get the lowdown on the statigraphy of this unnamed tributary of Cayuga Creek. Professor Jeff Over of SUNY Geneseo, world-famous conodont expert, stands ready with a laminated strat column chart. Joe Sullivan is on the left, Dan Krisher is on the right. Both are members of the Rochester Academy of Science Fossil Section, among other affiliations. Joe is an awesome amateur collector who is making rapid progress academically in paleo and is a voracious consumer of the literature. Dan is head geologist with Ward's Natural Science, a dream job for sure. Ask him about Silurian reefs!
NYSGA 2006 field trip B3, Stop 3. Photo taken an unnamed tributary of Cayuga Creek. The lip of these falls is a calcareous layer of the Geneseo Shale. Below that is a Leicester Pyrite lag deposit lens and below that is the Windom shale. At this locality, there is a lot going on between the Leicester and the North Evans Limestone.
Professor Gordon Baird points out the "grotesque" concretion layer on a strat column while standing directly in front of it. This is unit "h" from the NYSGA 2006 field trip B3 guide book, stop 3. Going up the statigraphic column, this unit is followed by the North Evans Limestone, a resistant layer of the Genundawa Limestone and then the West River Shale. This section is on an unnamed tributary of Cayuga Creek.
A ledge of the Leicester Pyrite, a prominent and resilient lag deposit containing reworked pryritic concretions from the underlying Windom shale, conodonts and fish bones. This photo was taken at Cazenovia Creek. The Leicester Pyrite is separated from the Genundawa Limestone by a layer of black shale.
This is the type section of the North Evans Limestone along Eighteenmile Creek, just downstream of the Amtrak bridge. The Genundawa Limestone lies at the water's edge. Owing to a particularly rainy fall, the North Evans is just below the water. A fisherman and Professor Over have a quiet conversation on this warm autumn morning
Exploring the Genundawa and North Evans Limestone at Eighteenmile Creek downstream of the Amtrak bridge. The shelf at thigh level is the Genundawa. The underlying North Evans has been throughly mined out here. From left to right, Dan Krisher, Kym Pocius, Bill Kirchgasser, Joe Sullivan, Andrew Bush and Jeff Over.
New York State Geological Association 2006 field trip B3, stop 1. From left to right, Dr. Bill Kirchgasser, SUNY Potsdam; Dan Krisher, Ward's Natural Science; Dr. Jeff Over, SUNY Geneseo; Dr. Gordon Baird, SUNY Fredonia; and Dr. Andrew Bush, University of Connecticut. Professor Baird explains that the North Evans Limestone is comprised of two million years of conodont zones, numerous fish spines, teeth, and plates. It extends eastward nominally to Taunton Gully in the Genesee Valley.
Professors Over and Baird display stratigraphic columns to explain the stratigraphy of the transition of the Hamilton Group to the Upper Devonion of New York. Seen in the background above the chart is the Genundawa Limestone, a deep water styolinid limestone that overlies the North Evans Limestone. Kym Pocius of the Rochester Academy of Science pays close attention.
Sunday, October 08, 2006
James Zambito / University of Cincinnati explains his final conclusions to a rapt audience of SUNY New Palz and Vassar students at the Lake Erie shore, where Eighteenmile Creek dumps out into the lake. This was followed by furious collecting in the trilobites beds of the exposed Wanaka Formation. Several nice Phacops rollups were found by a local youth donning a "Slayer" T-shirt and mullet.
Standing on the Tichnor limestone at Cazenovia Creek near the Route 20 bridge. The stream bed is comprised of Tichnor limestone. Above is the Windom formation. The whitish horizon in the middle of the picture is the Smoke Creek trilobite bed. Students from SUNY New Palz and Vassar pay close attention to a lecture by James Zambito (off camera to the right).
Lower Windom Formation exposed at Buffalo Creek. Students from SUNY New Palz and Vassar check out the sixth order deposition cycles in this local basin. This was part of an NYSGA field trip led by James Zambito. Of particular interest here were Ambocoelia horizons indicating dysoxic and low diversity enviroments. Mr. Zambito tracked these biofaces to test the hypothesis of coordinated stasis.