Earthquake near San Francisco, CA

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 21 km (13 mi) from the epicentre. In San Francisco, 14 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: Daly City 9 km, intensity II · Pacifica 14 km, intensity II · San Francisco 14 km, intensity II · South San Francisco 16 km, intensity II · Bayview-Hunters Point 16 km, intensity II · San Bruno 17 km, intensity II · Tamalpais-Homestead Valley 18 km, intensity II · Millbrae 21 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 220 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 70,000× the energy of this one
2. Magna, Utah 2020 M 5.7 50,000× the energy of this one
3. Around the size people start to feel M 3.0 4.4× the energy of this one
4. This earthquake M 2.6 about 220 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 4.4 on 2018-01-04 — about 520 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

1. 7.9 The 1906 San Francisco, California Earthquake · 4 km NNE of this epicentre Apr 18, 1906
2. 5.3 The 1957 San Francisco, California Earthquake · 9 km SE of this epicentre Mar 22, 1957

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 37.7183, -122.5657. Map © OpenStreetMap contributors.

Nearby places

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

30 earthquakes have been recorded within 50 km since this one.

1. 1.9 5km NNW of San Leandro, CA 18:46 UTC
2. 1.8 14km S of Bolinas, CA 14:32 UTC
3. 2.6 3km NW of Castro Valley, CA 23:28 UTC
4. 2.2 2km WNW of Orinda, CA 11:04 UTC
5. 2.1 2km NE of San Leandro, CA 19:47 UTC
6. 1.6 1km SSE of Palo Alto, CA 19:32 UTC
7. 2.3 2km ENE of San Leandro, CA 02:38 UTC
8. 1.7 3km WSW of San Francisco Zoo, CA 06:22 UTC
9. 2.1 1km ENE of El Cerrito, CA 08:30 UTC
10. 2.4 33km S of Point Reyes, CA 18:21 UTC
11. 1.7 12km WSW of Portola Valley, CA 21:14 UTC
12. 2.5 4km SE of Oakland, CA 15:30 UTC
13. 1.8 5km SSW of Port Costa, CA 06:42 UTC
14. 1.6 8km WNW of San Francisco Zoo, CA 15:37 UTC
15. 1.8 7km SSW of Muir Beach, CA 18:49 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 10:22 UTC. 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.