Outside experts were split in their opinions about the report, which is not yet published but is due to be presented at a meeting later this month.
The study said a relatively mild increase starting in 2001 comes from increased quake activity in a methane production area along the state line between Colorado and New Mexico. The increase began about the time that methane production began there, so there’s a “clear possibility” of a link, says lead author William Ellsworth of the USGS.
The increase over the nation’s midsection has gotten steeper since 2009, due to more quakes in a variety of oil and gas production areas, including some in Arkansas and Oklahoma, the researchers say.
It’s not clear how the earthquake rates might be related to oil and gas production, the study authors said. They note that others have linked earthquakes to injecting huge amounts of leftover wastewater deep into the earth.
There has been concern about potential earthquakes from a smaller-scale injection of fluids during a process known as hydraulic fracturing, or fracking, which is used to recover gas. But Ellsworth said Friday he is confident that fracking is not responsible for the earthquake trends his study found, based on prior studies.
Study ties oil, gas production to earthquakes in the Midwest but experts are split over report
