CO2 Sequestration, Petroleum Accumulation, and Groundwater Flow in Kansas: A Regional Assessment
by Timothy R. Carr and Daniel F. Merriam
There is a growing experience with CO2 disposal in deep saline aquifers. These aquifers hold promise in terms of storage capacity and proximity to emission sources to sequester geologically large quantities of carbon. Large, regional-scale open aquifers with good top seals (very low permeability layers) and extremely low rates of fluid migration can provide effective sequestration through hydrodynamic trapping. The Lower Paleozoic (Cambrian to Mississippian) aquifer systems in Kansas, Missouri, and Oklahoma comprise the Western Interior Plains aquifer system, one of the largest regional-scale saline aquifer systems in North America. Understanding hydrologic conditions and processes of this aquifer system provides insight to evolution of the various sedimentary basins across Kansas, migration of hydrocarbons out of the Anadarko and Arkoma basins, distribution of Arbuckle petroleum reservoirs across Kansas, and a basis to evaluate CO2 sequestration potential.
The Cambrian and Ordovician stratigraphic units form a saline aquifer that is in hydrologic continuity with the freshwater aquifer of the Ozark Plateau, providing an explanation for the under pressure within the Arbuckle Group. However, large-scale fluid movements provided hydrodynamic traps for hydrocarbons, and the opportunity to sequester large quantities of CO2. Using relational databases and geographic information systems estimated sequestration potential is generated for each square mile of the lower aquifer (Arbuckle Group) for the entire state of Kansas. Under any reasonable set of assumptions, the amount that could be stored in the Arbuckle Group by either displacement or dissolution is large and amounts to many years of United States CO2 emissions.