Earthquake · reviewed by a seismologist
M 3.0md
6km NNW of Bridgeport, CA
Yes. A magnitude 3.0 earthquake was recorded 6km NNW of Bridgeport, CA, at 8:50 am PST on 17 February 2021 (16:50 UTC), 2.7 km deep. 7 people have reported feeling it to USGS.
- When
- Magnitude
- M 3.0 (md)
- Depth
- 2.7 km below the surface
- Felt
- 7 reports · strongest reported intensity II
- Nearest
- Mono County, 55 km SE
- Nearest mapped fault
- Robinson Creek fault, 9 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2029 days ago
Earthquake alerts for Topaz Ranch Estates, NV
Get a notification in this browser when USGS records an earthquake near Topaz Ranch Estates, NV. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 36 km (22 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
How big was it?
This earthquake released about 920 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 370,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 16,000× the energy of this one
- Magna, Utah 2020 M 5.7 12,000× the energy of this one
- This earthquake M 3.0 about 920 lb of TNT
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
For this area
The largest earthquake within 50 km since 2016 was M 5.6 on 2016-12-28 — about 8,200 times the energy of this one.
Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:
- 5.8 3 km NE of Mono City, California · 30 km SSE of this epicentre
- 5.2 23 km S of Walker, California · 20 km W of this epicentre
- 5.2 31 km ENE of Mono City, California · 43 km ESE of this epicentre
- 5.1 23 km E of Bridgeport, California · 26 km E of this epicentre
- 5.1 19 km W of Bridgeport, California · 19 km WSW of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 38.3032, -119.2660. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mono County, CA | 55 km (34 mi) | SE | earthquakes near Mono County |
| Alpine County, CA | 58 km (36 mi) | NW | earthquakes near Alpine County |
| Tuolumne County, CA | 69 km (43 mi) | WSW | earthquakes near Tuolumne County |
| Douglas County, NV | 73 km (46 mi) | NNW | earthquakes near Douglas County |
| Mineral County, NV | 78 km (48 mi) | ENE | earthquakes near Mineral County |
| Lyon County, NV | 80 km (50 mi) | N | earthquakes near Lyon County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
39 earthquakes have been recorded within 50 km since this one.
- 2.4 31km ENE of Dardanelle, CA
- 2.4 32km SE of Markleeville, CA
- 2.6 30km ENE of Dardanelle, CA
- 3.0 29km ESE of Markleeville, CA
- 2.4 30km ENE of Dardanelle, CA
- 2.9 30km SE of Markleeville, CA
- 3.0 30km SE of Markleeville, CA
- 3.0 32km ENE of Dardanelle, CA
- 2.0 9 km ENE of Coleville, California
- 2.6 33km ENE of Dardanelle, CA
- 3.0 31km SE of Markleeville, CA
- 2.6 31km SE of Markleeville, CA
- 3.4 31km SE of Markleeville, CA
- 3.4 29km ENE of Dardanelle, CA
- 2.5 30km SE of Markleeville, CA
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.