The 2001-Present Induced Earthquake Sequence in the Raton Basin of Northern New Mexico and Southern Colorado

Abstract

We investigate the ongoing seismicity in the Raton Basin and find that the deep injection of wastewater from the coal-bed methane field is responsible for inducing the majority of the seismicity since 2001. Many lines of evidence indicate that this earthquake sequence was induced by wastewater injection. First, there was a marked increase in seismicity shortly after major fluid injection began in the Raton Basin in 1999. From 1972 through July 2001, there was one M ≥ 4 earthquake in the Raton Basin, whereas 12 occurred between August 2001 and 2013. The statistical likelihood that such a rate change would occur if earthquakes behaved randomly in time is 3.0%. Moreover, this rate change is limited to the area of industrial activity. Earthquake rates remain low in the surrounding area. Second, the vast majority of the seismicity is within 5 km of active disposal wells and is shallow, ranging between 2 and 8 km depth. The two most carefully studied earthquake sequences in 2001 and 2011 have earthquakes within 2 km of high-volume, high-injection-rate wells. Third, injection wells in the area are commonly very high volume and high rate. Two wells adjacent to the August 2011 M 5.3 earthquake injected about 4.9 million cubic meters of wastewater before the earthquake, more than seven times the amount injected at the Rocky Mountain Arsenal well that caused damaging earthquakes near Denver, Colorado, in the 1960s. The August 2011 M 5.3 event is the second-largest earthquake to date for which there is clear evidence that the earthquake sequence was induced by fluid injection.

Coping with earthquakes induced by fluid injection

“…Nonetheless, there is debate as to whether injected volume is the key factor that limits maximum magnitude ( 6) or whether it is controlled by the size of a nearby fault and its relation to the contemporaneous stress state, as is the case for natural earthquakes. Although faults evidently play at least several possible roles that affect the likelihood of inducing felt earthquakes, most of these faults are only detected when they are imaged by well-located induced earthquakes ( 3,14). SEISMIC HAZARD MODELS.…”

Search for hydraulic connectivity between surface reservoirs and surrounding aquifers in the reservoir-triggered seismic environment (Koyna region, India) using hydrochemical and isotopic signatures

“…and Bredehoeft 1981; Shapiro et al 2006;Rubinstein et al 2014). For all these processes, hydraulic conductivity of geological formation plays a vital role in the movement of fluids, which depends on the secondary features like fractures and fissures and their length, density, orientation, etc.…”

Induced Earthquakes Correlations With Earth’s Crustal Thickness

“…Those two locations in Colorado had an increase activity due not only for the waste water disposal wells, but the heavy coal bed exploration. [6] Texas had three important regions with the increasing of earthquakes one was in Dallas observed since 2009, the main characteristic of those earthquakes is the depth location reported as 5 km. In 2015 it is reported some events with depth ≥ 8 km.…”