Fracking is in the spotlight once again following a swarm of at least three dozen earthquakes in central Arkansas over the last week, CNN reports. Experts say they believe the quakes—the strongest of which was 3.5 magnitude—are natural, but they haven't ruled out a connection with natural gas exploration involving hydraulic fracturing in the region. Though two dozen of the quakes have hit near Morrilton, Arkansas, four different areas in the state saw activity.
"Right now all we've gotten reports of is shaking stuff and rattling shelves, but people are definitely noticing them," an Arkansas Geological Survey scientist says, describing the chances of so many quakes in the state in such a short time as "Powerball kind of odds," but noting that the closest injection wells to some of the quakes are eight miles away. "I can't say at this time there's not a connection, but given the distance from those wells, it would be pretty amazing." Another swarm of mild earthquakes in the next county over ended abruptly two years ago after a moratorium on new injection wells was imposed.