Earthquake · reviewed by a seismologist
M 1.8md
Earthquake near Mammoth Lakes, CA
No earthquake was likely felt in Mammoth Lakes in the 24 hours to 1:31 pm PST (21:31 UTC). The last one was M 2.9, 26 km (16 mi) SSE, at 3:54 am PDT on 24 October 2026, estimated intensity II (weak) in town. Every earthquake near Mammoth Lakes
This page: a magnitude 1.8 earthquake was recorded 47 km (29 mi) northeast of Mammoth Lakes, CA, at 11:39 pm PST on 11 March 2021 (07:39 UTC), 4.5 km deep.
USGS: 41km NNE of Toms Place, CA
- When
- 11:39 pm PST on 11 March 2021 ()
- Where
- 47 km (29 mi) northeast of Mammoth Lakes, CA · earthquakes near Mammoth Lakes
- Magnitude
- M 1.8 (md)
- Depth
- 4.5 km below the surface
- Felt
- no reports yet
- Nearest
- Mono County, 28 km W
- Nearest mapped fault
- White Mountains fault, 6 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 2067 days ago
Earthquake alerts for Mammoth Lakes, CA
Get a notification in this browser when USGS records an earthquake near Mammoth Lakes, CA. 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 minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth, people at rest would likely notice it out to about 13 km (8 mi) from the epicentre. In Mammoth Lakes, 47 km away, the estimate is intensity I (not felt). 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 16 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 930,000× the energy of this one
- Magna, Utah 2020 M 5.7 660,000× the energy of this one
- Around the size people start to feel M 3.0 59× the energy of this one
- This earthquake M 1.8 about 16 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 5.2 on 2020-04-11 — about 130,000 times the energy of this one.
Before 2016, the USGS record lists 56 earthquakes of M5 or more within 50 km; the five largest:
- 6.4 The 1986 Chalfant Valley, California Earthquake · 43 km SSE of this epicentre
- 6.3 The 1934 Excelsior Mountains, Nevada Earthquake · 44 km NNE of this epicentre
- 6.1 Near Tonopah Junction, Nevada · 49 km E of this epicentre
- 6.1 11 km WNW of Aspen Springs, California · 44 km SW of this epicentre
- 6.1 8 km W of Aspen Springs, California · 46 km SSW 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 37.9187, -118.5538. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Mono County, CA | 28 km (18 mi) | W | earthquakes near Mono County |
| Mineral County, NV | 68 km (42 mi) | N | earthquakes near Mineral County |
| Esmeralda County, NV | 82 km (51 mi) | E | earthquakes near Esmeralda County |
| Mariposa County, CA | 125 km (78 mi) | WSW | earthquakes near Mariposa County |
| Madera County, CA | 132 km (82 mi) | SW | earthquakes near Madera County |
| Alpine County, CA | 134 km (83 mi) | NW | earthquakes near Alpine County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
38 earthquakes have been recorded within 50 km since this one.
- 2.2 24 km S of Mina, Nevada
- 1.6 24 km S of Mina, Nevada
- 1.7 California-Nevada border region
- 1.6 38km NNE of Toms Place, CA
- 1.6 39km NNE of Toms Place, CA
- 1.9 40km NNE of Toms Place, CA
- 1.7 39km NNE of Toms Place, CA
- 2.1 27 km SSW of Mina, Nevada
- 2.8 39km NNE of Toms Place, CA
- 2.8 28 km SSW of Mina, Nevada
- 1.8 9km W of Toms Place, CA
- 1.5 13 km NW of Benton, California
- 1.6 41km NNE of Toms Place, CA
- 1.8 9km WSW of Toms Place, CA
- 1.5 28 km S of Mina, Nevada
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.