CCUS Opportunities in Southwestern Pennsylvania Oil Fields: Case Studies from the Midwest Regional Carbon Sequestration Partnership
The Midwest Regional Carbon Sequestration Partnership (MRCSP) has prepared a focused assessment of carbon capture utilization and storage (CCUS) opportunities in the tri-state area of Ohio, Pennsylvania and West Virginia. This area is home to both shallow and deep depleting oil and gas fields that are still actively produced; fields considered to be depleted; fields that have been converted to natural gas storage; and unconventional shale gas and oil/condensate fields. This mix of activity offers an array of potential options for miscible (approximated by reservoir depths of 2500 ft or more) and immiscible (<2500 ft) enhanced recovery and carbon storage in the Ohio River Valley. As part of this assessment, geologic case studies prepared for the Washington-Taylorstown, Linden and New Freeport fields have identified specific CCUS prospects (including stacked potential) for Washington and Greene counties in southwestern Pennsylvania. These include both miscible and immiscible CO2-enhanced oil recovery (CO2-EOR) and CO2-enhanced gas recovery (CO2-EGR) for Upper Devonian Venango Group reservoirs; carbon storage in the Lower Devonian Oriskany Sandstone; and possible future opportunities for CO2-EGR and carbon storage in the Middle Devonian Marcellus and Upper Ordovician Utica shales. These case study fields are proximal to CO2 point-sources derived from the power and industry sectors, which are located along the Ohio River to the west and Monongahela River to the east. The western flank of the Washington-Taylorstown Field offers miscible CO2-EOR opportunities in the Gordon sandstone (porosities of ~20 percent and permeabilities of 106-145 mD). The field’s eastern flank and adjoining Linden Field offer immiscible CO2-EOR opportunities in the Gantz and Gordon sandstones, and CO2-EGR in the Fifty-Foot sandstone. Like Washington-Taylorstown Field, the New Freeport Field offers miscible CO2-EOR in the Gordon sandstone, but what’s more, the overlying Nineveh and underlying Fourth sandstones also serve as miscible CO2-EOR targets, since the Venango Group is deeper in Greene County. Eastern Washington and Greene counties may offer multiple carbon storage opportunities. The depth to top of the Venango Group is greater here, and given the documented productivity of multiple Venango sandstones, stacked carbon storage may be possible. In addition, the underlying Oriskany Sandstone offers a deeper storage target when some Venango Group sandstones may be in the immiscible depth range. The prospect of applying CO2-EGR methods to shales, although yet untested in the Appalachian Basin, could bring an important nuance to future CCUS applications. Based on certain reservoir engineering and economic considerations, it is recommended that CO2-EOR applications focus on areas of wet gas production and do so at the latter stages of shale gas development, rather than waiting for reservoir depletion.
AAPG Datapages/Search and Discovery Article #90373 © 2019 AAPG Eastern Section Meeting, Energy from the Heartland, Columbus, Ohio, October 12-16, 2019