GREENBRIER, AR (AP) - Several more small earthquakes have been recorded by the U.S. Geological Survey in the Greenbrier and Guy areas.
The largest is a 3.8 magnitude quake recorded at 3:49 a.m. Thursday about four miles northeast of Greenbrier.
At least five other quakes with magnitudes of 2.3 to 2.6 have been recorded since shortly after 11 p.m. Wednesday.
No injuries or damage is reported. Geologists say quakes of magnitude 2.5 to 3.0 are generally the smallest felt by humans.
The U.S.G.S. has recorded more than 30 quakes in the area since Sunday, and 700 quakes have hit the region in the past six months. The cause remains somewhat of a mystery.
However, some experts say it's likely either a naturally occurring swarm or possibly related to natural gas exploration in the area.