KELLWASSER BED (HIGH FRASNAIN, UPPER DEVONIAN) EQUIVALENTS IN THE APPALACHIAN BASIN

In Europe and North Africa the Lower and Upper Kellwasser beds consist of organic-rich shales or carbonates within and interbedded with lighter carbonate strata. In the Appalachian Basin, the Kellwasser equivalents, correlated by conodont biostratigraphy, are currently recognized as discrete pyritic black shale or silty-shale beds within green-gray and lighter shales and siltstones. Both lower and upper equivalents are recognized in outcrop and in the subsurface. In western New York State the beds reach a maximum thickness in the Buffalo Creek Valley, thinning westward distal from the source area as indicated by scour marks and current aligned cephalopods, as well as thinning eastward toward the source area before grading into lighter colored strata.

The Pipe Creek Shale, the Lower Kellwasser equivalent, overlies the Angola Shale and the Nunda Sandstone. The Upper Kellwasser equivalent is a bed in the upper Hanover Shale. This bed is thin to the west (20 cm thick), reaching 70 cm thick in the valley of Buffalo Creek, and thinning to 24 cm in the Genesee River Valley. Westward the base of the shale is sharp and unbioturbated; the top is marked by 1 cm wide compacted burrows that occur in the lowest Famennian. The easternmost bed is very silty, bioturbation at the base decreases upward, laminations are thicker and less distinct. The Upper Kellwassser equivalent overlies green-gray shales to the west and siltstones of the Wiscoy Sandstone. The Kellwasser beds are not recognized in the Illinois and Michigan basins in equivalent strata, indicative of regional differences in depositional conditions.