The region on the west side of Yellowstone frequently has several small quakes per month, but on June 13, 2016, the tremor was larger than usual.
Indeed, a M4.3 quake rattled the mountains west of Yellowstone Park Monday morning at 6:14 a.m.
According to USGS, the M4.3 earthquake hit about 32 miles (52.0 km) west of West Yellowstone, Montana.
it was centered down near the Centennial Valley, west of Hebgen Lake over in the Southern Gravelly Mountains.
The main tremor was followed by 6 weaker aftershocks:
M1.3 – 51km W of West Yellowstone, Montana
M0.8 – 52km W of West Yellowstone, Montana
M1.4 – 52km W of West Yellowstone, Montana
M0.7 – 52km W of West Yellowstone, Montana
M0.9 – 52km W of West Yellowstone, Montana
M2.4 – 50km W of West Yellowstone, Montana
The remote area is lightly populated and only 3 residents have been awaken by the unusual tremblor.
An employee at nearby Henrys Lake State Park in Idaho says one worker awoke thinking a bear was shaking his cabin.
Montana’s earthquake activity is concentrated mostly in the mountainous western third of the State which lies within a seismic zone that also includes southeastern Idaho, western Wyoming, and central Utah.