Fracking’s seismic impact

Geologists are warning that fracking may be leading to an increase in seismic activity. A recent advisory from the U.S. Geological Survey warns that activities related to hydraulic fracturing—or fracking, extracting oil and natural gas from subterranean rock formations—has likely contributed to the recent spike in earthquakes in Oklahoma, and experts warn that the chances for a major quake in the region may be dramatically higher. The state averaged just two magnitude-3 or greater quakes per year between 1978 and 2008, but had recorded hundreds of quakes during a six months span alone in 2016. Arkansas, Ohio, Texas, and Colorado have also experienced higher numbers of earthquakes after fracking activities increased. Researchers believe that disposing of wastewater through high-pressure injections deep into the earth may be lubricating fault lines, resulting in a process known as injection-induced seismicity. “We haven’t seen this before in Oklahoma,” Robert Williams, a i USGS geophysicist, tells NBCNews.com. “But we know from other cases around the world that if you have an increasing number of small earthquakes, the chances of a larger one will go up.”