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

Robert Skoumal·Joern Ole Kaven·Jake Water
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Abstract

Oklahoma is one of the most seismically active places in the United States as a result of industry activities. In order to characterize the fault networks responsible for these earthquakes in Oklahoma, we relocated a large-scale template matching catalog between 2010-2016 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 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 which 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.

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Seismological Research LettersArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 33.616567° to 37.002206° latitude; -103.002434° to -94.431215° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Robert Skoumal, Joern Ole Kaven, Jake Water. 2019-05-29. Characterizing seismogenic fault structures in Oklahoma using a relocated template matched catalog. https://doi.org/10.1785/0220190045

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