Earthquake · reviewed by a seismologist
M 2.1ml
Earthquake near Calimesa, CA
No earthquake was likely felt in Calimesa in the 24 hours to 3:21 am PST (11:21 UTC). The last one was M 2.0, 7 km (4 mi) WSW, at 10:33 pm PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Calimesa
This page: a magnitude 2.1 earthquake was recorded 6 km (4 mi) west of Calimesa, CA, at 3:52 am PDT on 27 September 2018 (10:52 UTC), 17 km deep.
USGS: 7km W of Calimesa, CA
7 km (5 mi) SE of Redlands, CA · 119 km (74 mi) E of Los Angeles, CA
- When
- 3:52 am PDT on 27 September 2018 ()
- Where
- 6 km (4 mi) west of Calimesa, CA · earthquakes near Calimesa
- Magnitude
- M 2.1 (ml)
- Depth
- 17 km below the surface
- Felt
- no reports yet
- Nearest
- Orange County, 70 km WSW
- Nearest mapped fault
- Crafton Hills fault, 2 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 2942 days ago
Earthquake alerts for Calimesa, CA
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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 4 km (2 mi) from the epicentre. In Calimesa, 6 km away, the estimate is intensity II (weak). 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.
Earthquakes near other towns within 30 km: Mentone, Yucaipa, Redlands, Moreno Valley, Cherry Valley, Loma Linda.
How big was it?
This earthquake released about 51 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 300,000× the energy of this one
- Magna, Utah 2020 M 5.7 210,000× the energy of this one
- Around the size people start to feel M 3.0 19× the energy of this one
- This earthquake M 2.1 about 51 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 4.5 on 2018-05-08 — about 3,200 times the energy of this one.
Before 2016, the USGS record lists 24 earthquakes of M5 or more within 50 km; the five largest:
- 6.7 The 1918 San Jacinto, California Earthquake · 30 km SSE of this epicentre
- 6.3 The 1992 Big Bear, California Earthquake · 35 km NE of this epicentre
- 6.2 3 km SE of San Bernardino, California · 16 km NW of this epicentre
- 6.0 The 1910 Lake Elsinore, California Earthquake · 42 km SW of this epicentre
- 6.0 The 1986 North Palm Springs, California Earthquake · 47 km E 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 33.9993, -117.1230. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Orange County, CA | 70 km (44 mi) | WSW | earthquakes near Orange County |
| Los Angeles County, CA | 107 km (67 mi) | WNW | earthquakes near Los Angeles County |
| Riverside County, CA | 108 km (67 mi) | ESE | earthquakes near Riverside County |
| San Diego County, CA | 113 km (70 mi) | SSE | earthquakes near San Diego County |
| San Bernardino County, CA | 129 km (80 mi) | NE | earthquakes near San Bernardino County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
55 earthquakes have been recorded within 50 km since this one.
- 2.5 3km SW of Morongo Valley, CA
- 2.0 2km ESE of Loma Linda, CA
- 2.0 8km SE of Valle Vista, CA
- 2.1 8km NNE of Beaumont, CA
- 1.6 8km NNE of Beaumont, CA
- 1.8 11km NNE of Running Springs, CA
- 1.5 8km NNE of Beaumont, CA
- 1.6 7km SE of Home Gardens, CA
- 2.1 8km NNE of Beaumont, CA
- 1.8 14km N of Cabazon, CA
- 1.7 14km SSE of Big Bear Lake, CA
- 1.8 9km NNW of Banning, CA
- 1.9 9km SE of Valle Vista, CA
- 2.7 6km SSW of Banning, CA
- 1.8 6km SSE of Mentone, 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.