Yellowstone caldera volcano (Wyoming, USA): elevated seismic activity, but within normal activity range

November 3, 2012 – MONTANA – Yellowstone earthquake activity remains at background levels. During October 2012, 128 earthquakes were recorded in the Yellowstone National Park region. The largest were a pair of magnitude 3.1 events on October 14 at 8:55 PM and 9:21 PM MDT, located about 18 miles south southwest of West Yellowstone, MT. These events were part of a swarm of 55 quakes recorded October 14 -16, with magnitudes ranging from M 0.9 to M 3.1. The swarm resumed briefly on October 26 with an additional 8 events, M 1.4 to M 2.3 located in the same area on the western edge of the Madison Plateau. Slow subsidence of the caldera, which began in early 2010, continues. Current deformation patterns at Yellowstone are well within historical norms. –Volcano Discovery