Insurance Information Institute
- …Hydraulic fracturing, commonly known as fracking, is a drilling technique used to extract natural gas and oil from the ground. The process involves injecting large amounts of drilling fluids into wells. Critics charge that the wastewater produced by the process can cause drinking water to be polluted. But some energy companies, state authorities and environmentalists contend that poor construction of wells, rather than the process itself, is the cause of the pollution. There is, however, some evidence that fracking has contributed to an increase in the number of earthquakes. In March 2013 researchers at the University of Oklahoma, Columbia University and the U.S. Geological Survey determined that the 5.7 magnitude earthquake that hit Oklahoma in 2011 was caused by the disposal of wastewater from oil production. The findings were published in the journal Geology. In April 2012 the U.S. Geological Survey released a study that concluded that a series of earthquakes in the middle of the U.S. was the result of human activity and that fracking could be the cause.
- In March 2015 the U.S. Geological Survey released a report showing that the recent small earthquakes across Oklahoma, which have been linked to fracking, are reactivating long dormant fault lines that are 300 million years old. The new research concludes that the faults could produce quakes with far higher magnitudes than the more than 3,600 small tremors that were recorded in central Oklahoma from 2009 through 2014. The report will be used to develop a new earthquake hazard map for Oklahoma that the survey will issue later in 2015.