A magntiude 3.0 earthquake struck on the Arizona-New Mexico border just before 7 am this morning, and residents in both states report feeling it. The preliminary epicenter calculated by the USGS is about 3-4 miles south of Duncan Highway - US70 between Lordsburg and Safford. [right, orange star marks epicenter. Credit, USGS]
AZGS has a temporary seismic station in the area following the Duncan M-5.3 earthquake of 2014, so we should be able to provide a more accurate location once those data are analyzed. We are still seeing numerous aftershocks from that event.
Today's quake is roughly 10 miles south-southeast of Duncan and near the eastern edge of the aftershock zone from the 2014 main quake. [Below, location of the 2014 Duncan main shock and aftershocks through September 2014. Credit, Jeri Young, AZSG]
I speculate that today's event is yet another in the ongoing aftershocks of that M=5.3 quake.
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