Earthquakes used to be uncommon in Middle America. But in the last decade, quakes numbers have skyrocketed in Oklahoma and Kansas. The major uptick in seismic activity has risen alongside the growth of oil and gas production in the area. When fossil fuel companies dispose of wastewater by injecting it into underground wells, the increased pressure deep in the earth can trigger tremblors.
Now, in a new study, researchers say that not only have earthquakes in Oklahoma grown more frequent, they have also gotten deeper, as oilfield wastewater sinks and creates high pressure environments deep underground where earthquakes start. The research suggests wastewater may continue to sink and increase pressure that can trigger earthquakes for another 10 years even after oil and gas companies eventually stop injecting wastewater into underground wells.
“Our study implies that simply turning off the injection wells will not immediately stop the earthquakes,” said Virginia Polytechnic ...
