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Hundreds of earthquakes per day: The 2014 Guthrie, Oklahoma, Earthquake Sequence

Harley M. Benz·Nicole D McMahon·R Aster·Daniel E. McNamara·David J. Harris
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Abstract

A remarkable increase in seismic activity in Oklahoma since 2009 has been shown to correlate closely with enhanced hydrocarbon extraction and associated wastewater disposal; 99% of this recent Oklahoma earthquake activity has occurred within 15 km of a call II injection well (Ellsworth, 2013). In response to this increase in seismic activity, the U.S. Geological Survey (USGS) partnered with the Oklahoma Geological Survey (OGS) to exchange waveform data from permanent and temporary seismic stations to improve the cataloging of earthquake source parameters for a broad region of north-central Oklahoma. For a particularly persistent earthquake sequence near Guthrie, Oklahoma, a subspace detection method is applied to data from nearby seismic stations. This approach documents the occurrence of hundreds of readily detectable, highly similar, earthquakes per day, with rates occasionally exceeding 1000 earthquakes per day. Time-varying changes in b-value appear episodic, suggesting a correlation with periods of reversible fault weakening and associated failure.

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Seismological Research LettersArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 35.776043045943254° to 35.94465937365276° latitude; -97.58537292480469° to -97.27020263671875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Harley M. Benz, Nicole D McMahon, R Aster, Daniel E. McNamara, David J. Harris. 2015-07-22. Hundreds of earthquakes per day: The 2014 Guthrie, Oklahoma, Earthquake Sequence. https://doi.org/10.1785/0220150019

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