The University of Utah Seismograph Stations (UUSS) continues to monitor the Yellowstone earthquake swarm, with over 1,200 quakes registered this year.
1,284 quakes have been registered as of 9:45 MDT July 19th. 2017. The swarm began June 12th, 2017.
We previously reported a 4.5 magnitude quake rattled West Yellowstone and Gardiner, Montana June 16, 2017. It was the largest quake in the region since March 2014, when a 4.8 magnitude quake struck the same area.
A few days later, we reported over 460 quakes had been registered in and around Yellowstone. Indeed, 2014 saw a noticeable uptick in earthquake activity, similar to the trend this year.
According to a UUSS press release, most of the quakes in the Yellowstone earthquake swarm have been minor in nature. The figures mentioned in the paragraph are below, courtesy of UUSS:
The swarm began on June 12th, 2017 and, as of 09:45 MDT on July 19th, 2017, is composed of 1,284 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, 7 earthquakes in the magnitude 3 range, 105 earthquakes in the magnitude 2 range, 407 earthquakes in the magnitude 1 range, 736 earthquakes in the magnitude 0 range, and 28 earthquakes with magnitudes of less than zero. These events have depths from ~0.0 km to ~14.0 km, relative to sea level. At the time of this report, there were 125 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). In addition, four other earthquakes in the swarm have been reported felt.
In addition, you can see a video of registered earthquake activity at the swarm’s hub below, courtesy of UUSS.
Earthquakes are a common occurrence around Yellowstone National Park, owing to its proximity to a fault line. According to UUSS, quakes “comprise about 50% of the total seismicity in the Yellowstone region.” Indeed, most tremors around Yellowstone go unnoticed. If you do notice any quake activity around Yellowstone, please send a tip to the U.S. Geological Survey.
UUSS will continue to monitor the Yellowstone earthquake swarm and provide updates as needed.