The Oklahoma Geological Survey Statewide Seismic Network

Abstract

The Oklahoma Geological Survey (OGS) monitors seismicity throughout the state of Oklahoma utilizing permanent and temporary seismometers installed by OGS and other agencies, while producing a real-time earthquake catalog. The OGS seismic network was recently added to the Advanced National Seismic System (ANSS) as a self-supporting regional seismic network, and earthquake locations and magnitudes are automatically reported through U.S. Geological Survey and are part of the ANSS Comprehensive Earthquake Catalog. In Oklahoma, before 2009, background seismicity rates were about 2 M 3.0+ earthquakes per year, which increased to 579 and 903 M 3.0+ earthquakes in 2014 and 2015, respectively. After seismicity peaked, the rate fell to 624, 304, and 194 M 3.0+ earthquakes in 2016, 2017, and 2018, respectively. The catalog is complete down to M 2.2 from mid-2014 to present, despite the significant workload for a primarily state-funded regional network. That astonishing uptick in seismicity has been largely attributed to wastewater injection practices. The OGS provides the Oklahoma Corporation Commission, the agency responsible for regulating oil and gas activities within the state, with technical guidance and earthquake products that inform their “traffic-light” mitigation protocol and other mitigating actions. We have initiated a citizen-scientist-driven, educational seismometer program by installing Raspberry Shake geophones throughout the state at local schools, museums, libraries, and state parks. The seismic hazard of the state portends a continued need for expansion and densification of seismic monitoring throughout Oklahoma.

Cross Validation of Stress Drop Estimates and Interpretations for the 2011 Prague, OK, Earthquake Sequence Using Multiple Methods

“…(2017) (5,262 earthquakes, Mc M L ‐0.8 from November 4, 2011 to December 4, 2011). The magnitudes of these two catalogs are calculated differently with the OGS catalogs magnitudes being the Richter magnitude (J. I. Walter et al., 2020), while the subspace‐detected catalog uses detection magnitudes, which are magnitudes estimated based upon nearby reference catalog earthquakes (McMahon et al., 2017). We refer to both of these magnitudes using M L .…”

“…The catalogs for earthquake and fault plane solutions are obtained from OGS which can be downloaded from https://www.ou.edu/ogs/research/earthquakes/catalogs (J. I. Walter et al., 2020). The aftershock catalog of McMahon et al.…”

“…The catalogs for earthquake and fault plane solutions are obtained from OGS which can be downloaded from https://www.ou.edu/ogs/research/earthquakes/catalogs (J. I. Walter et al, 2020). The aftershock catalog of McMahon et al (2017) are available at the U.S. Geological Survey ScienceBase website (https:// www.sciencebase.gov/catalog/item/595276c6e4b062508e3c7650 last accessed August 2020).…”

An Analysis of Abandoned Oil Well Characteristics Affecting Methane Emissions Estimates in the Cherokee Platform in Eastern Oklahoma

“…HF to induce production from unconventional wells is a common practice in the Cherokee Platform and has been known to cause seismic disturbances in the area (Bills Walsh, 2017). However, no abandoned wells surveyed during this study were located <1 km of an earthquake epicenter (Table S3) (Walter et al, 2020). The closest earthquake, which occurred in 2016, was a magnitude 2.4 on the Richter scale and was 3.2 km away from the nearest surveyed well.…”

rsudp: A Python package for real-time seismic monitoring with Raspberry Shake instruments

“…The uses of low-cost seismographs in science and education are becoming more widely known as these devices become more popular (Anthony et al, 2018;Diaz et al, 2020;Lecocq et al, 2020;Subedi et al, 2020;Walter et al, 2019;Winter et al, 2021). Raspberry Shake seismographs are commonly used in schools, by Shake community members, and other individuals having no formal training in seismology.…”