Earthquake · reviewed by a seismologist
M 1.7ml
Earthquake near Alpine, CA
No earthquake was likely felt in Alpine in the 24 hours to 9:17 am PST (17:17 UTC). The last one was M 4.9, 155 km (96 mi) ESE, at 10:27 am PST on 3 November 2026, estimated intensity II (weak) in town; 321 felt reports to USGS. Every earthquake near Alpine
This page: a magnitude 1.7 earthquake was recorded 47 km (29 mi) east-northeast of Alpine, CA, at 12:03 am PDT on 18 June 2026 (07:03 UTC), 12 km deep.
USGS: 26 km SSW of Ocotillo Wells, CA
81 km (51 mi) E of San Diego, CA
- When
- 12:03 am PDT on 18 June 2026 ()
- Where
- 47 km (29 mi) east-northeast of Alpine, CA · earthquakes near Alpine
- Magnitude
- M 1.7 (ml)
- Depth
- 12 km below the surface
- Felt
- no reports yet
- Nearest
- San Diego County, 47 km W
- Nearest mapped fault
- Elsinore fault, 7 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 147 days ago
Earthquake alerts for Alpine, CA
Get a notification in this browser when USGS records an earthquake near Alpine, 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 2 km (1 mi) from the epicentre. In Alpine, 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.
Earthquakes near other towns within 30 km: Pine Valley.
How big was it?
This earthquake released about 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
- Around the size people start to feel M 3.0 92× the energy of this one
- This earthquake M 1.7 about 10 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 2025-04-14 — about 190,000 times the energy of this one.
Before 2016, the USGS record lists 15 earthquakes of M5 or more within 50 km; the five largest:
- 6.6 The 1942 Fish Creek Mountains, California Earthquake · 46 km E of this epicentre
- 6.6 The 1968 Borrego Mountain, California Earthquake · 31 km NNE of this epicentre
- 6.6 The 1987 Superstition Hills, California Earthquake · 41 km E of this epicentre
- 6.4 The 1954 San Jacinto Fault, California Earthquake · 43 km NNE of this epicentre
- 6.2 The 1987 Elmore Ranch, California Earthquake · 48 km ENE 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 32.9470, -116.2795. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| San Diego County, CA | 47 km (29 mi) | W | earthquakes near San Diego County |
| Imperial County, CA | 87 km (54 mi) | E | earthquakes near Imperial County |
| Riverside County, CA | 91 km (56 mi) | NNE | earthquakes near Riverside County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
45 earthquakes have been recorded within 50 km since this one.
- 1.8 10 km NE of Ocotillo Wells, CA
- 2.3 14 km ENE of Borrego Springs, CA
- 2.6 28 km SSW of Ocotillo Wells, CA
- 1.6 7 km NNW of Ocotillo, CA
- 1.7 5 km ENE of Ocotillo Wells, CA
- 1.6 14 km ESE of Pine Valley, CA
- 3.0 24 km WSW of Westmorland, CA
- 1.9 9 km S of Borrego Springs, CA
- 1.6 9 km S of Borrego Springs, CA
- 1.5 6 km SE of Ocotillo, CA
- 2.3 20 km SW of Ocotillo Wells, CA
- 1.6 12 km N of Ocotillo Wells, CA
- 2.4 10 km N of Borrego Springs, CA
- 1.9 12 km NNE of Ocotillo Wells, CA
- 2.4 27 km ENE of Pine Valley, 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.