CHARACTERIZATION OF THE HELDERBERG GROUP AS A GEOLOGIC SEAL FOR CO2 SEQUESTRATION

The Midwest Regional Carbon Sequestration Partnership (MRCSP) is one of seven regional partnerships established by the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL) to study carbon sequestration as one option for mitigating climate change. This partnership recognizes that both the Devonian Oriskany Sandstone and the Silurian Salina Group offer potential for subsurface carbon dioxide storage in northern West Virginia. The Siluro-Devonian Helderberg Group lies stratigraphically between these two units. Predominantly a carbonate interval with minor interbedded siliciclastics and chert, the Helderberg was deposited in an ancient epeiric sea. Although most previous investigations of this unit have concentrated on outcrops in eastern West Virginia, new information is available from an injection well drilled along the Ohio River at First Energy's R. E. Burger electric power plant near Shadyside, Ohio. Geophysical, seismic, and core data from this well have been combined with existing outcrop information to evaluate the Helderberg Group's potential as a geologic seal. The data collected have shown that only secondary porosity remains and permeability, if it exists, most likely occurs along faults or within fractures.