The United States Geological Survey says two earthquakes struck Colorado overnight. The first, with a magnitude of 3.2, was about 20 miles south of Trinidad near the New Mexico border at about 1 a.m. Another quake with a preliminary 4.3 magnitude struck just after 4 a.m. Friday about 24 miles south-southwest of White River City in northwest Colorado.
The epicenter of the second quake was about 41 miles east of Dinosaur National Monument. It was located at a depth of three miles. There was no immediate report of damage or injuries.
USGS is reporting a 4.3 magnitude earthquake in Western Colorado this morning. Residents on Facebook say it shook their houses, and woke many people up @CBSDenver. Mesa County friends, did you feel it?? #CBS4Mornings pic.twitter.com/uA2YQb4gzI— Makenzie O'Keefe (@makenziepokeefe) August 24, 2018
The second quake was not far from an underground nuclear test site in the 1970s. The Kiowa County Press adds some context:
In 1973, three nuclear devices were detonated at a site three miles northeast of Friday's earthquakes as part of a joint research project by the U.S. government and private companies to determine if natural gas could be recovered from sandstone using nuclear explosives. All three 33-kiloton devices were detonated at least one mile beneath the surface. Two test wells drilled in the area later in the year produced over 120 million cubic feet of natural gas over a five-month period. Decommissioning of the site began in 1976.
There's been a number earthquakes in the U.S. of late:
- A magnitude 6.3 earthquake struck Wednesday night in Alaska. The Alaska Earthquake Center says the quake occurred in the remote Andreanof Islands region.
- That same day, USGS reported an initial quake with a preliminary magnitude of 6.2 struck just after 1:30 a.m., more than 170 miles west of Coos Bay, about 220 miles southwest of Portland.