A 2.7 magnitude earthquake occurred in eastern South Dakota early Thursday morning just before 4 am, marking the 52nd such instance in the state since 1872.
The earthquake, centered near Humboldt, was relatively shallow and unlikely to be felt by those on the lower floors of buildings.
South Dakota’s seismic activity is attributed to smaller faults and tectonic plate movements, with the strongest recent earthquake registering a magnitude 4 in 2011.