28 Paleozoic Events and Processes: Sedimentary Geology, Paleontology, and Geochemistry

The focus of this session is short- to long-term geologic, paleobiologic, and geochemical events and processes, recorded in Paleozoic sedimentary rocks.

Monday, 23 March 2026
3:25 PM - 5:30 PM
CCC, Room 27

Updates on Stratigraphic Correlation of the Frasnian/Famennian Boundary Interval (Upper Devonian) in New York

Paper number: 28-4
Program: Technical Sessions
Time: 4:30 PM – 4:50 PM

Authors

Abstract

The Late Devonian mass extinction consisted of two pulses, the Lower Kellwasser Event (LKE) in the late Frasnian and the Upper Kellwasser Event (UKE) at the Frasnian/Famennian boundary. At deeper-water sections in western New York, conodont biostratigraphy places the LKE within the Pipe Creek Formation and the UKE (Frasnian/Famennian boundary) at the Point Gratiot Bed in the upper Hanover Formation, just below the contact with the Dunkirk Formation. The stratigraphic placement of these events in shallow-marine strata farther east (e.g., Allegany and Steuben counties) has proved more difficult and controversial due to a paucity of conodonts and ammonoids. Traditionally, correlations with western New York have been established through lithostratigraphy, although brachiopods are useful in correlating among shallow-marine sections.

 

Wiscoy Creek in Wiscoy, New York, is a key stratigraphic section due to its intermediate location and paleoenvironment. At this section, a thick interval of dark gray shale that overlies the Wiscoy Formation has been correlated previously with either the Dunkirk Formation or the Pipe Creek Formation. However, new collections of conodonts (Over 2025, doi: 10.1130/abs/2025NE-407407) indicate that this dark shale is latest Frasnian in age, with the Frasnian/Famennian boundary placed near its upper boundary, making it correlative with the Point Gratiot Bed. A positive carbon isotope excursion is consistent with this interpretation. We discuss the implications of these findings for east-west stratigraphic correlations in New York and for interpretations of the Late Devonian mass extinction. All interpretations of the data pose some difficulty: either (1) the Wiscoy Creek section has been correlated incorrectly with locations farther east, or (2) atrypid brachiopods persisted into the early Famennian in the Appalachian Basin.

Geological Society of America Abstracts with Programs. Vol. 58, No. 2

doi: 10.1130/abs/2026NE-411147

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