Moderate mag. 3.9 earthquake - 9.5 mi south of Stanley, Custer County, Idaho, USA, on Thursday, 31 Dec 2020 10:26 pm (GMT -7) -

Moderate mag. 3.9 earthquake - 9.5 mi south of Stanley, Custer County, Idaho, USA, on Thursday, 31 Dec 2020 10:26 pm (GMT -7)

Moderate magnitude 3.9 earthquake at 10 km depth

1 Jan 05:41 UTC: First to report: USGS after 15 minutes.
Update Fri, 1 Jan 2021, 05:45
Small tremor of magnitude 3.9 just reported 9 miles south of Stanley, Idaho, United States
3.9 quake 31 Dec 10:26 pm (GMT -7)
3.9 quake 31 Dec 10:26 pm (GMT -7)
Just 19 minutes ago, a 3.9-magnitude earthquake struck near Stanley, Custer County, Idaho, USA. The tremor was recorded late at night on Thursday 31 December 2020 at 10:26 pm local time, at a shallow depth of 6.2 miles below the surface.
The event was filed by the United States Geological Survey (USGS), the first seismological agency to report it.
Our monitoring service identified a second report from the European-Mediterranean Seismological Centre (EMSC) which listed the quake at magnitude 3.9 as well.
Based on the preliminary seismic data, the quake should not have caused any significant damage, but was probably felt by many people as light vibration in the area of the epicenter.
Weak shaking might have been felt in Stanley (pop. 68) located 9 miles from the epicenter.
Other towns or cities near the epicenter where the quake might have been felt as very weak shaking include Challis (pop. 1000) located 46 miles from the epicenter, Idaho City (pop. 470) 47 miles away, and Hailey (pop. 8,100) 50 miles away.
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Earthquake data:

Date & time: 1 Jan 2021 05:26:07 UTC -
Local time at epicenter: Thursday, 31 Dec 2020 10:26 pm (GMT -7)
Magnitude: 3.9
Depth: 10.0 km
Epicenter latitude / longitude: 44.081°N / 114.9533°W (Custer County, Idaho, United States)
Nearest volcano: Shoshone (111 km / 69 mi)
Nearby towns and cities:
15 km (9 mi) S of Stanley (pop: 68) --> See nearby quakes!
81 km (50 mi) NW of Hailey (Blaine County) (pop: 8,130) --> See nearby quakes!
113 km (70 mi) ENE of Boise (pop: 146,000) --> See nearby quakes!
120 km (75 mi) ENE of Eagle (Ada County) (pop: 23,600) --> See nearby quakes!
127 km (79 mi) ENE of Meridian (pop: 90,700) --> See nearby quakes!
135 km (84 mi) ENE of Kuna (Ada County) (pop: 17,200) --> See nearby quakes!
143 km (89 mi) ENE of Nampa (pop: 89,800) --> See nearby quakes!
147 km (91 mi) ENE of Hamburg Siding (pop: 51,700) --> See nearby quakes!
173 km (108 mi) NNW of Twin Falls (pop: 47,500) --> See nearby quakes!
244 km (152 mi) WNW of Idaho Falls (pop: 59,200) --> See nearby quakes!
Weather at epicenter at time of quake:
Broken Clouds -6°C (21 F), humidity: 85%, wind: 1 m/s (2 kts) from SSE
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 4.5 x 1010 joules (12.4 megawatt hours, equivalent to 10.7 tons of TNT) More info
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Data for the same earthquake reported by different agencies

Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.
MagnitudeDepthLocationSource
M 3.910 km15 Km S of Stanley, Idaho, USAUSGS
M 4.03 kmSOUTHERN IDAHO, USAEMSC

User reports for this quake (3)

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
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10 miles north of soda springs (247.6 km ESE of epicenter) [Map] / Weak shaking (MMI III) / rattling, vibrating / 5-10 s : Our house has been shaking for the last couple of days shaking the walls for about 10 seconds about a minute apart.
Caldwell Idaho (146.1 km WSW of epicenter) [Map] / Weak shaking (MMI III)
twin falls / Very weak shaking (MMI II) / horizontal (sideways) swinging / very short
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