Weak mag. 2.1 earthquake - 3km W of Cobb, CA, USA, on Thursday, Mar 11, 2021 at 9:40 pm (GMT -8)


Weak magnitude 2.1 earthquake at 2 km depth
12 Mar 05:42 UTC: First to report: USGS after 2 minutes.
12 Mar 20:16: Magnitude recalculated from 2.2 to 2.1. Hypocenter depth recalculated from 1.7 to 1.9 km (from 1.1 to 1.2 mi).
12 Mar 20:16: Magnitude recalculated from 2.2 to 2.1. Hypocenter depth recalculated from 1.7 to 1.9 km (from 1.1 to 1.2 mi).
Earthquake details
Date & time | Mar 12, 2021 05:40:22 UTC |
Local time at epicenter | Thursday, Mar 11, 2021 at 9:40 pm (GMT -8) |
Status | Confirmed |
Magnitude | 2.1 |
Depth | 1.9 km |
Epicenter latitude / longitude | 38.818°N / 122.76067°W ![]() |
Antipode | 38.818°S / 57.239°E |
Shaking intensity | Weak shaking near epicenter |
Felt | 0 reports |
Primary data source | USGS (United States Geological Survey) |
Nearest volcano | Clear Lake (17 km / 11 mi) |
Nearby towns and cities | 3 km (2 mi) W of Cobb (pop: 1,780) | Show on map | Quakes nearby 18 km (11 mi) W of Hidden Valley Lake (pop: 5,580) | Show on map | Quakes nearby 19 km (12 mi) SSE of Kelseyville (pop: 3,350) | Show on map | Quakes nearby 19 km (12 mi) SW of Clearlake (Lake County) (pop: 15,200) | Show on map | Quakes nearby 22 km (14 mi) E of Cloverdale (Sonoma County) (pop: 8,810) | Show on map | Quakes nearby 25 km (15 mi) NNE of Russian River (Sonoma County) (pop: 11,700) | Show on map | Quakes nearby 25 km (15 mi) NNE of Russian River (pop: 11,700) | Show on map | Quakes nearby 31 km (19 mi) N of Windsor (Sonoma County) (pop: 27,500) | Show on map | Quakes nearby 42 km (26 mi) N of Santa Rosa (pop: 175,000) | Show on map | Quakes nearby 89 km (55 mi) NW of Fairfield (pop: 113,000) | Show on map | Quakes nearby |
Weather at epicenter at time of quake | Clear Sky ![]() |
Estimated seismic energy released | 8.9 x 107 joules (24.8 kilowatt hours) | about seismic energy |
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.
Mag. | Depth | Location | Source |
2.1 | 1.9 km | 3km W of Cobb, CA, USA | USGS |
2.2 | 2 km | NORTHERN CALIFORNIA, USA | EMSC |
User reports for this quake
At magnitude 2.1, such a quake wouldn't normally be felt by people except under very favorable conditions.User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
Earlier earthquakes in the same area
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