Comparison between potential induced seismicity in the Raton Basin, Colorado and New Mexico, 2008-2010, and seismicity above the Socorro magma body, New Mexico

Jenny Nakai (1,2), Anne Sheehan (1,2), Matthew Weingarten (1), Susan Bilek (3)

Abstract
The rate of seismicity in the Raton Basin of Colorado and New Mexico has increased dramatically since 2000, and the region has been the locus of intense hydrocarbon extraction and fluid waste injection during that same time period. Detailed aftershock surveys were conducted by the USGS following the 2001 magnitude 4.6 and 2011 magnitude 5.3 earthquakes, and a private seismic network has been deployed since 2012. In this study we focus on the time period that the EarthScope USArray seismic network was deployed in the region from 2008-2010, supplemented by data from the coincident PASSCAL CREST experiment. A catalog of 1,884 earthquakes complete to local magnitude ML 1.2 in the Raton Basin in Colorado and New Mexico was located using P and S wave arrivals for the time period May 1, 2008 to February 28, 2010. A cluster of earthquakes is located at the center of five high volume injection wells and align on an apparent fault surface. The temporal evolution of earthquake epicenters is compared to the relative volume of injection at nearby wells. The seismicity rate and distribution will be compared to the Socorro magma body, a seismically active region in which fluid flow or pressure induced triggering are likely causes of earthquakes. To present a complete picture, historical seismicity of the two sites will be examined to 1973.