The earthquake swarm continues in northwest Arizona near the Nevada border. There were more than a dozen events during the past week, with the largest being a magnitude 2.7 yesterday (Sunday) just after noon. A magnitude 1.9 event just one minute later. [Right, epicenters of last weeks quakes shown by yellow dots. The orange dots are from Sunday's quakes. Credit, USGS]
The swarm began on March 28 and more than 50 earthquakes have been recorded so far. Swarms in other areas have lasted for months in some cases.