Marissa Hall | Shale Plays Media
The rise in earthquakes in areas such as Colorado and New Mexico has been directly linked to wastewater injection, a process used frequently in the oil and gas industry during fracking.
The conclusion comes from a group of scientists who conducted a study with the U.S. Geological Survey. The results were published Tuesday in the Bulletin of the Seismological Society of America. According to Emily Atkin for ThinkProgress.org, the study suggests that wastewater disposed underground after drilling is actually finding its way into dormant fault lines, disrupting their current stress levels and ultimately causing the activity.
For their research, the four California-based USGS scientists monitored the 2,200 square mile Raton Basin, which goes from southern Colorado into New Mexico. They pointed out that the Basin had been “seismically quiet” until 1999, when companies began “major fluid injection” deep into the ground. Earthquakes began in 2001 when Colorado wastewater injection rates were under 600,000 barrels per month, and and since then there have been 16 earthquakes that could be considered large (above a magnitude of 3.8, including two over a 5.0 magnitude), compared with only one — a 4.0 magnitude quake — in the 30 years prior.
The sudden change that took place in the frequency of earthquakes in the Raton Basin indicates that the quakes probably were not caused by “random fluctuations underground.” However, the scientists did recognize that, while the date obtained points to a very direct link between the wastewater injection and quakes, the study is not the final, definitive voice on the matter.
For all the details, see Atkin’s full story: Scientists find ‘direct link’ between earthquakes and process used for oil and gas drilling