Earthquake · reviewed by a seismologist
M 2.1ml
Earthquake near Julian, CA
No earthquake was likely felt in Julian in the 24 hours to 8:33 pm PST (04:33 UTC). The last one was M 4.9, 151 km (94 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 Julian
This page: a magnitude 2.1 earthquake was recorded 5 km (3 mi) west-northwest of Julian, CA, at 11:22 pm PDT on 1 August 2017 (06:22 UTC), 15 km deep.
USGS: 5km WNW of Julian, CA
56 km (35 mi) NE of San Diego, CA · 40 km (25 mi) E of Escondido, CA
- When
- 11:22 pm PDT on 1 August 2017 ()
- Where
- 5 km (3 mi) west-northwest of Julian, CA · earthquakes near Julian
- Magnitude
- M 2.1 (ml)
- Depth
- 15 km below the surface
- Felt
- no reports yet
- Nearest
- San Diego County, 15 km SW
- Nearest mapped fault
- Elsinore fault, 8 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 3303 days ago
Earthquake alerts for Julian, CA
Get a notification in this browser when USGS records an earthquake near Julian, 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 10 km (6 mi) from the epicentre. In Julian, 5 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.
Likely felt in: Julian 5 km, intensity II. Estimated for each town centre; each link is that town's own record.
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 5.2 on 2016-06-10 — about 36,000 times the energy of this one.
Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:
- 6.0 16km WSW of Oasis, CA · 50 km NE of this epicentre
- 5.5 1km ENE of Borrego Springs, CA · 32 km ENE of this epicentre
- 5.4 20km NNW of Borrego Springs, CA · 38 km NNE of this epicentre
- 5.3 18km ESE of Anza, CA · 44 km NNE of this epicentre
- 5.2 10km ESE of Anza, CA · 48 km N 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 33.1033, -116.6473. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| San Diego County, CA | 15 km (9 mi) | SW | earthquakes near San Diego County |
| Riverside County, CA | 92 km (57 mi) | NE | earthquakes near Riverside County |
| Orange County, CA | 123 km (76 mi) | WNW | earthquakes near Orange County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
59 earthquakes have been recorded within 50 km since this one.
- 1.5 9km NE of Aguanga, CA
- 2.0 7km NW of Ocotillo Wells, CA
- 1.6 7km NW of Ocotillo Wells, CA
- 1.6 9km ESE of Palomar Observatory, CA
- 1.7 9km NE of Aguanga, CA
- 1.6 3km SE of Lake Henshaw, CA
- 3.0 2km SSE of Lake Henshaw, CA
- 1.8 23km ESE of Anza, CA
- 1.7 9km NE of Aguanga, CA
- 1.9 8km NE of Aguanga, CA
- 1.8 8km NE of Aguanga, CA
- 1.7 8km NE of Aguanga, CA
- 2.3 10km NE of Julian, CA
- 1.6 9km NE of Aguanga, CA
- 1.6 7km S of Borrego Springs, 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.