Earthquake risk drops for the central and eastern U.S., USGS report says

By Jennifer Hiller of The San Antonio Express-New. Excerpts:

"About 3.5 million people live in areas with increased risk of earthquake damage tied to the oil and gas industry, according to the latest U.S. Geological Survey of quakes linked to human activity.

A large swath of Oklahoma, including Oklahoma City, and southern Kansas continues to face an earthquake risk on par with California’s.

Overall, though, the earthquake hazard risk is lower than 2016, when the forecast placed more than 7 million people in the central or eastern U.S. in areas with potential for damaging earthquakes caused by human activity — the same portions of Oklahoma and Kansas at risk this year, plus the Dallas-Fort Worth metroplex.

Because there were no damaging quakes in the Dallas-Fort Worth region in 2016, it was removed from the hazard list for this year. South Texas, where the Eagle Ford Shale oil field stretches 400 miles, also doesn’t face any increased risk of earthquake damage this year, according to the report."

"“The story is generally good in terms of potential damage,” said Mark Petersen, chief of the USGS National Seismic Hazard Mapping Project."

"The Oklahoma Corporation Commission, that state’s oil and gas regulator, has placed limits on wastewater injection in some areas, and the USGS said those limits may have contributed to the drop in earthquakes last year."

"A 2016 study from researchers at the University of Texas at Austin and Southern Methodist University showed that oil and gas activity has triggered most of the earthquakes in Texas for decades. The study linked earthquakes to the energy industry for nearly as long as there has been oil drilling in Texas."