Forecasts of Induced Seismicity and its Hazard from a Hydromechanical Earthquake Nucleation Model

Justin L. Rubinstein, Jack H. Norbeck, & Andrew J. Barbour

Submitted August 12, 2019, SCEC Contribution #9448, 2019 SCEC Annual Meeting Poster #033

We apply a seismicity model based on a rate-and-state friction framework to study the induced earthquakes in Oklahoma and Kansas. This model uses fluid pressures computed following the assumption that pressure changes are dominated by reservoir compressibility effects. Using data from all of the injection wells in the Arbuckle group, we compute the stressing conditions over the 24-year period of January 1995 through 2018. Subsequently, we calculate seismicity rate forecasts over a broad range of spatial scales. The forecasts replicate many of the important characteristics of earthquake behavior including the timing of the onset and peak of seismicity, as well as the reduction in seismicity following decreased disposal rates. This forecast outperforms an observational seismicity rate forecast model for one-year forecast durations over the period 2009 - 2018. We also use these rate forecasts to compute the 1-year induced earthquake hazard over the same time-frame. We find that the observed ground shaking is consistent with hazard forecasts based both on the hydromechanical model described above as well as a statistical model. The hazard forecasts based upon the hydromechanical earthquake rate model outperforms those from the statistical model. This demonstrates that future USGS induced seismicity hazard forecasts should include earthquake rate models that consider the physics underpinning induced seismicity.

Citation
Rubinstein, J. L., Norbeck, J. H., & Barbour, A. J. (2019, 08). Forecasts of Induced Seismicity and its Hazard from a Hydromechanical Earthquake Nucleation Model . Poster Presentation at 2019 SCEC Annual Meeting.


Related Projects & Working Groups
Earthquake Forecasting and Predictability (EFP)