A Geochemical Assessment of the Utica Shale in the Mohawk Valley of New York Evidence for Diachronous Deposition and Ramifications for Potential Hydrocarbon Systems

William Thompson-Butler
Harvard University, Department of Earth and Planetary Sciences, 2013

Utilizing carbon isotope and uranium/lead geochronological data sampled from two river outcrops in the Mohawk Valley, Canajoharie and Nowadaga Creek, I propose a diachronous deposition model for the Utica Shale unit deposited in the foredeep of the Taconic Orogeny. Additionally, the variable nature of the Total Organic Carbon (TOC) content throughout the unit as well as the lack of covariance between ^TM13C values for organic and carbonate carbon are investigated.

The Mohawk Valley of New York contains numerous outcroppings of deposits from the Middle to Late Ordovician phase of the Taconic Orogeny. Existing work on the region has utilized these outcrops to perform biostratigraphic analyses correlating fossil zones and ash beds between outcrops. Although low-resolution, these techniques have laid the foundation for further work in the area by creating well-documented, lithostratigraphy- based organizational models. The advent of higher-resolution geochemical techniques for the analyses of rock units and ash beds has led to an influx of data and opportunities to build on or recreate these older basin formation and deposition models.

By improving current basin models, producers will be better suited for the economic exploitation of current reserves as well as the discovery of new reservoirs. Continued carbon isotope and geochronological analyses of the Utica Shale will provide insights with important ramifications for the hydrocarbon potential of the unit.

AAPG Search and Discovery Article #90182©2013 AAPG/SEG Student Expo, Houston, Texas, September 16-17, 2013