A 4.7-magnitude earthquake that researchers described as the largest in Arkansas in 35 years was recorded late Sunday night near Greenbrier. It was the latest in a swarm of quakes that has bedeviled the region since early last fall.
Sunday’s quake, which occurred around 11 p.m. and was felt in at least five states, surpassed all others recorded in this or any of the previous swarms, said Scott Ausbrooks, a state geological survey researcher.
He said that the fault along which the quakes were occurring could yield an earthquake measuring up to 5.5 magnitude if it were to erupt all at once. But he said that was unlikely.