Jeffrey Johnson quoted in National Geographic article

Photo of Storm clouds hover over a field in Oklahoma. Geologist there have been chasing down unusual signal in their seismic data that grew in frequency and spread as the summer wore on.

Jeffrey Johnson, an associate professor of geosciences, was quoted in a recent National Geographic article titled, “Mysterious waves have been pulsing across Oklahoma.”

It begins: “IT ALL STARTED when a wave swept across Oklahoma on June 24, just before 11:11 a.m. local time. It buzzed one seismometer after another, seeming to ping-pong hundreds of miles across the state. This wave didn’t just breeze by—it pulsed like a geologic heartbeat for about 10 minutes.”

In the piece, Johnson posits that seismometers are picking up unidentified sound waves.