Quake data: Reported (unconfirmed) earthquake: 10.four mi northeast of San Francisco, California, USA, 28 April 2021 07:39 GMT
Although our monitoring service initially determined network activity typical of an earthquake, there was no confirmation from a national or international seismological agency. Because of this, it is highly unlikely that it was caused by an earthquake.
28 Apr 08:00 UTC: First report: VolcanoDiscovery after 22 minutes.
I felt this tremor
I didn’t feel it
Date and time: April 28, 2021 07:39:09 UTC –
Size: unknown
Depth: 10.0 km
Latitude / Longitude of epicenter: 37.85024 ° N / 122.25432 ° W. 
(California, USA)
Nearest volcano: Clear Lake (132 km)
Primary data source: VolcanoDiscovery
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Data for the same earthquake reported by different authorities
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| size | depth | place | source |
| not specified | n / A | Near San Francisco, California, USA | VolcanoDiscovery |
User reports for this quake (1)
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94618 (0 km southwest of the epicenter) [Map] / Weak shaking (MMI III) / 2-5 s : As near, close to the surface. Brief shudder after a slight jolt.
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