Seismicity in the Northern Delaware Basin

Abstract:

Investigation of seismicity in the northern Delaware Basin began in the early 1970s when the seismic activity of the region was assessed for the location of the future Waste Isolation Pilot Plant (WIPP), a storage facility for transuranic waste. While this area has a relatively sparse history of tectonic seismic activity, the Delaware Basin has long been the site of significant oil and gas extraction that has been tied to induced seismicity in the region. The New Mexico Tech Seismological Observatory (NMTSO) began monitoring the area around the WIPP site on a continuous basis in the 1990s, and the network was upgraded several times in the intervening years to reach its current configuration of 11 mixed short-period and broadband stations. Temporary seismic networks, including the 3-component broadband SIEDCAR campaign, have also been used to study seismicity in the region. Additionally, stations installed in recent years by the USGS and TexNet provide improved coverage of the area.

The most significant cluster of seismicity in the New Mexico portion of the Delaware Basin occurred between 2000 and 2012 in the Dagger Draw oil field, northwest of Carlsbad. Until very recently, seismic activity in the northern Delaware Basin outside this cluster remained low compared to the rise in seismic activity in the southern Delaware Basin in Texas. However, in the past year seismic activity in the New Mexico portion of the Delaware Basin has risen sharply, with 304 earthquakes larger than M1.5 located by the NMTSO in this region the first half of 2020, compared to 18 for the same period in 2019. These events were predominantly located in 2 clusters, one near Hobbs, NM about 50 km northeast of the WIPP site with the largest event a M3.3 that occurred on June 28, 2020, and one in southeastern Eddy county about 35 km south of the WIPP site, which includes several M2.7 events. In response to this rise in activity, the NMTSO has begun efforts to install additional seismic monitoring stations in the area. Here we present a summary of historic and current seismic monitoring efforts and seismicity in the northern Delaware Basin, and how this data can be understood in the broader context of Permian Basin seismicity.