CARBON SEQUESTRATION POTENTIAL OF THE ORISKANY SANDSTONE IN PENNSYLVANIA REVISITED

With greenhouse gas mitigation remaining a legislative priority in Pennsylvania and renewable generation technologies still unable to provide electric power at efficient quantities and rates, coal and gas fired power plants with carbon capture and sequestration (CCS) could serve much of the state’s and countries electricity need in the near future. CCS is a technology that provides a near-term solution to reduce anthropogenic CO₂ emissions to the atmosphere and reduce our impact on the climate system. CCS involves a set of technologies for CO2 capture, transport, and sequestration. The last step in this chain, geologic carbon sequestration, is the placement of CO₂ into an appropriate geologic formation in such a way that it will remain permanently sequestered from the atmosphere. This research continues earlier work on estimating carbon storage capacity in the Oriskany sandstone formation of PA using stochastic methods to determine parameters for input into a volumetric equation meant for saline formations. The prior work developed a method to determine the thickness, depth, porosity (as a function of depth), and density of CO₂ (as a function of temperature and pressure). Porosity, pressure, and temperature were determined using the depth to the top of the Oriskany formation plus half the thickness in that location. While the outcomes could be representative values for subregions where the Oriskany sandstone is thin, in areas where it is thick the values are average estimates. In this research, a GIS approach is used to divide the depth of the Oriskany formation into sub-layers and each layer is valued at its respective depth. Considering that depth is the independent variable for the mass storage of CO₂ a more robust estimation is offered by discretizing the depth of the Oriskany formation. The methods used in this research are generalized and can be applied elsewhere in similar geologic settings. If CCS is to be utilized at a wide level, accurate estimation of carbon storage potential is necessary to provide guidance for government and industry leaders to plan for its development.