Record Oklahoma Earthquakes Caused By Deep Fracking Wastewater: Study

Oklahoma has been experiencing a record number of earthquakes and a new study says that deeply injected fracking wastewater may be to blame. The research comes from the University of Bristol, which says that wastewater injection depth is "strongly linked" to the number of earthquakes the state has experienced. These man-made earthquakes have been called a national security threat due to the risk they pose.

Oklahoma is something like an earthquake hotspot, but humans are to blame. That has been the case for the better part of a decade, but more recently the state has experienced a huge uptick in these tremors. As the University points out, Oklahoma has seen the number the number of man-made earthquakes since 2011 increase 800-fold.

It's no secret fracking is linked to man-made earthquakes — in fact, the USGS has an entire web page dedicated to the topic — but the reasons for the rapid increase in the past several years has been without a clear answer. That may have changed thanks to this newly published study, though.

The USGS explains that the majority of induced earthquakes are not the result of hydraulic fracking, but rather the wastewater disposal wells. Oklahoma is the biggest victim of these earthquakes, but only between 1% and 2% of them result from hydraulic fracking. The rest, says the USGS, are caused by wastewater injection.

According to the newly published study, which also comes from Resources for the Future and Delft University of Technology, the wastewater's injection depth has a huge role in the number of man-made earthquakes that result. As well, the research indicates that decreasing the injection depth so that it is above basement rocks may "sinifically reduce" how much energy these earthquakes release every year.

SOURCE: University of Bristol