A new study out in Science by US Geological Survey scientist William Ellsworth links earthquakes to wastewater injection sites. These earthquakes, thought to be caused by pressure changes due to excess fluid injected deep below the surface, are being dubbed “man-made” earthquakes.
It's not the first time scientists have used that moniker, as earthquakes have been associated with other industrial operations that mess with underground formations such as surface and underground mining or dams that impound water into reservoirs.
Yet, in more recent years, we're seeing more and more of them,
“The number of earthquakes has increased dramatically over the past few years within the central and eastern United States. More than 300 earthquakes above a magnitude 3.0 occurred in the three years from 2010-2012, compared with an average rate of 21 events per year observed from 1967-2000.”
Many likely know that “wastewater” is a byproduct of many fossil fuel processes. It can come from raw material itself or is a leftover from purification steps during the extraction and processing phases of fuel production.