The United States Geological Survey, or USGS, concludes that fracking is contributing to the rising amount of earthquakes throughout the Midwest. Part of the fracking process causes injection-induced seismicity. This occurs when water, sand and chemicals are pumped underground during hydraulic fracking to extract natural gas and oil. The added pressure can cause long dormant fault lines to begin shifting, resulting in an earthquake.
The USGS shows a strong link between increased seismic activity and regions where fracking wastewater has been disposed of underground. In parts of Oklahoma, it notes that seismic activity has increased by 70 times since fracking activity began. Looking at the central and eastern U.S., the trend toward higher seismic activity continues.
From 1973 to 2008, there was an average of 21 earthquakes of magnitude three or greater. Yet in 2014 alone, there was a recorded 659 magnitude three or greater earthquakes recorded. Most of these earthquakes were between magnitudes three and four, not enough to cause much damage.
However, scientists at the USGS are alarmed that these earthquakes are becoming more powerful. In 2011, Prague, Oklahoma was rocked by a 5.6 magnitude earthquake believed to have been caused by wastewater injection, which left 14 homes destroyed and two people injured. The same year, near Trinidad, Colorado, a 5.3 magnitude earthquake was recorded, which was fortunately in a remote area and caused no damage.