Characterizing seismogenic fault structures in Oklahoma using a relocated template-matched catalog

Abstract

Oklahoma is one of the most seismically active places in the United States as a result of industry activities. To characterize the fault networks responsible for these earthquakes in Oklahoma, we relocated a large-scale template-matching catalog between 2010 and 2016 using the GrowClust algorithm. This relocated catalog is currently the most complete statewide catalog for Oklahoma during this seven year window. Using this relocated catalog, we identified seismogenic fault segments by developing an algorithm (FaultID) that clusters earthquakes and then identifies linear trends within each cluster. Considering the large number of earthquakes in Oklahoma, this algorithm made the process of identifying previously unmapped seismogenic faults more approachable and objective. We identify approximately 2500 seismogenic fault segments that are in general agreement with focal mechanisms and optimally oriented relative to maximum principle stress measurements. We demonstrate that these fault orientations can be used to approximate the maximum principle stress orientations.