A 5.8-magnitude earthquake struck in western Montana early Thursday morning, waking people up more than 30 miles from its epicenter, and felt as far away as Spokane, Washington. The magnitude 5.8 quake occurred at 12:30 a.m. MDT (local time), about 6 miles (10 km) southeast of Lincoln, Montana, according to the U.S. Geological Survey (USGS). CBS Missoula affiliate KPAX-TV reported no immediate reports of injuries, but said 9-1-1 call centers were swamped with calls and was advising people to only call if they were injured. KMVT-TV in Twin Falls, Idaho reported power outages around the earthquake’s epicenter. USGS gave these details:
Geographic coordinates: 46.899N, 112.586W
Depth: 4 km
Universal Time (UTC): 6 Jul 2017 06:30:16
Time near the Epicenter: 6 Jul 2017 00:30:16
Location with respect to nearby cities:
9.5 km (5.9 mi) SE of Lincoln, Montana
54.1 km (33.6 mi) NW of Helena, Montana
99.6 km (61.8 mi) N of Butte, Montana
107.3 km (66.5 mi) E of Missoula, Montana
111.0 km (68.8 mi) N of Butte-Silver Bow (Balance), Montana
Earthquakes do occur periodically in Montana, but this one was relatively strong – therefore relatively rare – for the region.
Rare 5 8 earthquake strikes western Montana, the area's strongest temblor in at least 20 years https://t.co/xBLnB2ho2I
— Giang (@GiangNews) July 6, 2017
USGS also provided this background:
Western Montana and northwestern Wyoming have experienced at least 16 other M 5+ earthquakes within 300 km of the July 6, 2017 event over the preceding century. The largest was the August 1959 M 7.2 Hebgen Lake earthquake – the largest historic event in the intermountain region – which occurred about 280 km to the south-southeast of the July 6 event. The Hebgen Lake earthquake triggered a large landslide that resulted in significant damage and more than 28 fatalities. A M 6.9 earthquake just over 100 km to the southeast of the July 6th earthquake in June, 1925, caused significant damage, but no fatalities. A M 5.6 earthquake occurred 170 km to the south of the July 6th event in July 2005, and caused minor damage in the surrounding region.
Bottom line: The 5.8-magnitude earthquake in western Montana on Thursday, July 6, 2017, is expected to be followed by aftershocks.
Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.