Streamflow modulation of earthquake swarms in central Oklahoma
The Jones earthquake swarm in central Oklahoma contributes to a significant portion of the sharply increased seismicity in the central US since 2009. The spatial distribution of seismicity closely follows the curves of the Canadian River. The correlation between daily seismicity rate and river gage height/discharge rate is statistically significant, with a mean time delay of 167 days. For 9 individual earthquake swarms within the Jones region, two sets of independently measured hydraulic diffusivities – from seismicity migration and time delay between peak discharge rate and seismicity rate, are consistent. Five swarms have significantly different diffusivities measured from the two methods, and two are located within close proximity to disposal wells. A wide range of diffusivities and seismicity orientations are observed, which suggest strong heterogeneous fault zone structure. The observed spatial-temporal distribution of seismicity clusters suggests seismic responses to localized stress perturbations within critically stressed fault zone. Further analysis with high-resolution earthquake locations and localized stress histories will help to illuminate details of the earthquake triggering processes.
AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015