The southwest side of Yellowstone Lake, the largest body of water in Yellowstone National Park, is experiencing quite an uptick in seismic activity today, Thursday, September 10.
According to the United States Geological Survey (USGS), Yellowstone experiences about 1,500 to 2,500 located earthquakes per year, many occurring in swarms, or earthquakes that cluster in time and space. Most swarms are small, containing 10-20 earthquakes, and short, lasting for one to two days.
Today's seismic activity is a little abnormal in that as of 4 pm Thursday, 93 earthquakes, and counting, have occurred all within this area of Yellowstone Lake since Wednesday night, according to USGS data. All but seven of the earthquakes have been under 2.5 magnitude. None have reached 3.0 magnitude.
In the same area depicted in the map below, 108 earthquakes have been recorded over the past 30 days, including today's activity. That means only 15 earthquakes were recorded in the area before today.