Modeling Potential Scenarios for Induced Seismicity in Arbuckle Group Saline Aquifer in Southern Kansas

Abstract

One of the characteristics of the Unconventional Mississippian Lime Play development is high water cuts. The Cambro-Ordovician Arbuckle Group with saline aquifer characterized by stratigraphic isolation, high permeability, and lowered regional hydrostatic pressure served as an excellent resource for waste brine disposal. However, spatial and temporal correlations of high volume brine disposal and seismic events in Harper and Sumner Counties of South-Central Kansas raised concerns that the seismic events in named areas might be anthropogenically induced. The geologic models were created for the Wellington Field and for the current area of increased seismicity (Harper and Sumner County, Southern Kansas) based on available log, 3D and 2D processed seismic, passive seismic, and core data. Permeability models were correlated with available Step Rate Test and Interference Test analyses. Geomechanical and structural models were introduced via seismic data processing, image log analysis, and core examination. Reservoir numerical simulations were performed, where multiple permeability realizations were introduced and flow barriers and preferential flow paths were suggested. Historical injection rates for brine disposal and fluid level changes were correlated in numerical simulations. As a result of numerical and geomechanical modeling it is possible to select several scenarios, where brine disposal could trigger movement in preferably oriented faults.

AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015