Ongoing Yellowstone Earthquake Swarm North of West Yellowstone, MT.
The University of Utah Seismograph Stations (UUSS) is monitoring an earthquake swarm which is currently active on the western edge of Yellowstone National Park. The swarm began on June 12th, 2017 and, as of 10:00 MDT on June 16th, 2017, is composed of 235 events with the largest magnitude of ML 4.4 (MW 4.4) (Figure 1). The swarm consists of one earthquake in the magnitude 4 range, 3 earthquakes in the magnitude 3 range, 41 earthquakes in the magnitude 2 range, 123 earthquakes in the magnitude 1 range, 62 earthquakes in the magnitude 0 range, and 5 earthquakes with magnitudes of less than zero. These events have depths from ~0.0 km to ~14.5 km, relative to sea level. At the time of this report, there were 101 felt reports for the M4.4 event that occurred on June 16, 2017 at 00:48:46.94 UTC (June 15, 2017 at 18:48:46.94 MDT). The M4.4 event has an oblique strike-slip moment tensor solution (Figures 1 & 2).
Earthquake swarms are common in Yellowstone and, on average, comprise about 50% of the total seismicity in the Yellowstone region.
Courtesy of quake.utah.edu