YELLOWSTONE NATIONAL PARK — According to Mike Poland, scientist-in-charge of the Yellowstone Volcano Observatory, during the month of April there were 168 earthquakes in the Yellowstone Region.
“This is sort of normal, background seismicity for the area,” Poland said.
The University of Utah Seismograph Stations, which operates and analyzes data from the Yellowstone seismic network, located the earthquakes.
The largest event of April was a magnitude 2.5 earthquake that happened on April 15, located below the eastern side of Shoshone Lake. This was one of about 50 earthquakes that occurred in mid-April.
An additional “swarm,” as Poland puts it, of 33 earthquakes happened near West Thumb towards the end of the month.
The rest of the earthquakes were relatively evenly distributed throughout the region with a more concentrated belt between Hebgen Lake and the area of Norris Geyser Basin, which is expected as it’s the most seismically active part of the park. Poland says this concentration is due to the stress changes caused by the 1959 Hebgen Lake earthquake.
Additionally, Poland confirmed that while the seismometer and temperature monitoring network for Steamboat Geyser, the tallest active geyser in the world, are still down, there were no confirmed eruptions in April. The last confirmed Steamboat eruptions were two in January, and it has remained quiet since then.
The Steamboat seismometer and temperature monitoring network are set to be repaired in the coming month as field work becomes possible. However, Poland notes that the amount of snow still present in the park in May could pose problems to planned projects that include strengthening monitoring networks, collecting data and conducting research on Yellowstone volcanic activity.
