paleonet More on KY mystery fossil

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Folks,

Thanks for the responses to date. A bit more information on the Borden and 
New Albany formations.

The Mississippian Borden formation consists of a series of red-green-gray 
shales and siltstones deposited generally in a prodelta setting. The Nancy 
Member, the most likely unit from which the specimen is derived, is 
primarily a greenish-gray to light olive-gray silty shale with few fossils 
(mostly scarce crinoid columnals and a few bryozoan impressions).

The Devonian New Albany is a thin laminated, fissile, black carbonaceous 
pyritic shale. Fish plates, conodonts, a few brachiopods, and plant 
fragments are the most common fossils. In general, the New Albany is 
generally considered to have been deposited in an anoxic basin. The 
equivalent Ohio shale in the Appalachian Basin eastward seems to be much 
deeper water, while the Chattanooga shale to the southwest along the 
Cincinnati Arch seems to be shallower water.

Nautiloids are possible in both formations, but are very rare.

Currently the responses seem to favor:
1) an orthoconic nautiloid that has been squished
2) an arthropod (guesses include eurypterid and cruiziana)

Brandon C. Nuttall

BNUTTALL@KGS.MM.UKY.EDU Kentucky Geological Survey
(859) 257-5500                  University of Kentucky
(859) 257-1147 (fax)                    228 Mining & Mineral Resources Bldg
http://www.uky.edu/KGS/home.htm Lexington, Kentucky 40506-0107