SPORE ZONATION THROUGH THE LATE DEVONIAN (STRUNIAN) CATTARAUGUS AND OSWAYO FORMATIONS OF NEW YORK AND THE HUNTLEY MOUNTAIN FORMATION OF PENNSYLVANIA: A BASIS FOR PALEOCLIMATIC INTERPRETATION

Palynologic and sedimentologic analyses of samples from 3 cores and 20 exposures of Latest Devonian diamictite-bearing strata of the central Appalachians and their apparent stratigraphic equivalents disclose a range of facies within 4 “Strunian” (uppermost Famennian) palynozones.

Relative appearances of zonal spore taxa in New York State compared with European “Strunian” sequences show discrepancies. In New York there is a thick sequence with variants of Vallatisporites at its base but the lepidophyta-literatus[LL] palynozone which directly overlies this zone in Europe is not seen in NY where variants of Vallatisporites are common. Outcrops of the Huntley Mountain Formation at Blossburg, PA however, disclose lepidophyta in possible LL [LE?] zone strata.

Possible LL Zone species occur below the Cattaraugus/Oswayo boundary in NY, and in the Huntley Mountain Formation at Blossburg. R. lepidophyta s.s. has not been found with certainty below the Oswayo Formation. The species does occur in PA sections but some of these belong to the LE Zone. Samples associated with diamictite are usually poorly preserved but are dominated by R. lepidophyta and in samples from 4 locations, explanatus [LE] occurs. In these latter occurrences small varieties of R. lepidophyta also occur. K. literatus, R. lepidophyta var. lepidophyta (and vars. tener and minor) are present in the Huntley Mountain Formation at Blossburg [LL,LE?] and the Oswayo [LE] and Kushequa Formations [LN] only.

Poorly preserved, highly carbonised spore assemblages from sequences in southern- and central-Pennsylvania belong to a broad PL (pusillites – lepidophyta) Zone with possible LE assemblages in sequences below the Murrysville Sandstone at Cramer, PA. The spores are often compared with those from northwest PA and western NY.

Spore diversity increases through the Latest Devonian in these regions and the number of spore taxa ranges from 23-31 (Lower Cattaraugus [V Zone]) to 46 – 62 taxa (Kushequa [LN Zone]). The assemblages from NY and PA are apparently unlike Western Europe because of the early abundance and variety of Vallatisporites and the apparent late appearance of lepidophyta and literatus. Statistical analysis of Vallatisporites variants is presently underway to provide additional stratigraphic resolution and to reduce the reliance on relatively few index species used in other regions.