A PALEONTOLGICAL EXAMINATION OF MIDDLE DEVONIAN BIVALVE MOLLUSCS AT THE COLE HILL OUTCROP IN MADISON COUNTY, NEW YORK

Middle Devonian pelecypods were collected from the Delphi Station Member of the Skaneateles Formation of the Hamlilton Group in Madison County, Central New York. The initial study was done to catalog specific fauna of the Cole Hill Road outcrop for the first time in over a century and to gain a better understanding of the paleoenvironment of the unit (a moderate to active mid-delta/shelf setting). With few exceptions, all of the pelecypod species previously documented were in fact identified during this study.

Bivalves dominated in the mid-level shale layer of the unit. Species collected from the same layer also follow the ecological principle of one species dominant in each environmental niche. A change in the size of the bivalves in the different layes was also noted; smaller fossils were found predominantly in the finer-grained lower layer of the outcrop, while larger specimens were more abundant in the coarser-grained upper layers. Random orientations of the specimens and the preservation of both valves in the pelecypods suggest a sporadic rapid storm deposit cycle. Additional refinements, a complete collection of the faunal asemblage, and more detail study of the stratigraphy are needed to gain a comprehensive depositional and paleoecological history of the formation.