Earthquake · reviewed by a seismologist
M 3.5mw
12km N of Delta, B.C., MX
Yes. A magnitude 3.5 earthquake was recorded 12km N of Delta, B.C., MX, 62 km (38 mi) W of Yuma, AZ, at 3:31 am MST on 18 October 2020 (10:31 UTC), 20 km deep. 19 people have reported feeling it to USGS.
62 km (38 mi) W of Yuma, AZ
- When
- Magnitude
- M 3.5 (mw)
- Depth
- 20 km below the surface
- Felt
- 19 reports · strongest reported intensity IV
- Measured shaking
- intensity VI (ShakeMap)
- Nearest
- Imperial County, 66 km NNW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2104 days ago
Earthquake alerts for San Luis, AZ
Get a notification in this browser when USGS records an earthquake near San Luis, AZ. 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 60 km (37 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.
Likely felt in: Calexico 38 km, intensity II · Holtville 43 km, intensity II. Estimated for each town centre; each link is that town's own record.
How big was it?
This earthquake released about 2.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 63,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 2,800× the energy of this one
- Magna, Utah 2020 M 5.7 2,000× the energy of this one
- This earthquake M 3.5 about 2.7 tons of TNT
- Around the size people start to feel M 3.0 this one released 5.6× more
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 in our catalogue was M 4.8 on 2018-11-19 — about 95 times the energy of this one.
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 32.4648, -115.1780. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Imperial County, CA | 66 km (41 mi) | NNW | earthquakes near Imperial County |
| Yuma County, AZ | 124 km (77 mi) | ENE | earthquakes near Yuma County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
52 earthquakes have been recorded within 50 km since this one.
- 2.4 5km NNE of Delta, B.C., MX
- 2.5 4km ENE of Delta, B.C., MX
- 2.3 8km N of Delta, B.C., MX
- 2.4 3km ENE of Delta, B.C., MX
- 2.9 4km ENE of Delta, B.C., MX
- 3.4 10km NNE of Delta, B.C., MX
- 2.3 9km N of Delta, B.C., MX
- 2.1 8km N of Delta, B.C., MX
- 1.8 8km N of Delta, B.C., MX
- 1.6 20km W of Delta, B.C., MX
- 2.1 9km W of Alberto Oviedo Mota, B.C., MX
- 1.6 20km W of Delta, B.C., MX
- 1.7 7km SW of Progreso, B.C., MX
- 3.3 18km W of Delta, B.C., MX
- 2.5 5km SW of Alberto Oviedo Mota, B.C., MX
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.