Using hypocenter-mapped fault structures for regional seismic risk analysis: A case study of Oklahoma County

Quantifying the seismic hazard and the associated risk from anthropogenic earthquakes is challenging due to the short historical record of earthquakes. Most earthquakes in stable continental regions such as Oklahoma occur on previously unmapped faults, and even known faults often have poorly understood characteristics. In this work, we map hidden fault structures from a precisely located earthquake hypocenters. The dimensions of the faults are estimated, and maximum possible earthquake magnitudes are then calculated using fault scaling relationships. These faults and magnitude models can then be used to generate a catalog of scenarios for seismic risk analyses. We generate scenarios for Oklahoma County in this manner and perform a regional seismic risk analysis using adapted Hazus 4.2 methodology. Results highlight the direct financial losses stemming from damage to residential buildings. This approach can be used as a screening tool for further risk analysis and to potentially assist operational and regulatory decision-making.