Earthquake near Willow Creek, CA

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Willow Creek, 22 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.

How big was it?

This earthquake released about 400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

1. Mineral, Virginia 2011 M 5.8 38,000× the energy of this one
2. Magna, Utah 2020 M 5.7 27,000× the energy of this one
3. Around the size people start to feel M 3.0 2.4× the energy of this one
4. This earthquake M 2.8 about 400 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 2019-02-06 — about 290 times the energy of this one.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

1. 6.4 The 1954 Eureka-Arcata, California Earthquake · 46 km WSW of this epicentre Dec 21, 1954
2. 5.6 15 km SW of Burnt Ranch, California · 41 km SSW of this epicentre Aug 20, 1927
3. 5.6 26 km NNW of Willow Creek, California · 33 km WNW of this epicentre Feb 13, 2012
4. 5.4 3 km NNW of Burnt Ranch, California · 25 km SSW of this epicentre Apr 30, 2008
5. 5.0 4 km NE of Fieldbrook, California · 49 km W of this epicentre Jun 3, 1935

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 41.0497, -123.4158. Map © OpenStreetMap contributors.

Nearby places

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. 2.4 11km WSW of Willow Creek, CA 08:12 UTC
2. 2.6 5km SW of Somes Bar, CA 03:09 UTC
3. 2.2 24km NW of Hayfork, CA 11:29 UTC
4. 2.8 7km W of Weitchpec, CA 03:10 UTC
5. 2.9 29km ENE of Willow Creek, CA 00:36 UTC
6. 2.3 10km SE of Willow Creek, CA 04:56 UTC
7. 2.2 9km ESE of Willow Creek, CA 06:18 UTC
8. 2.4 21km SSE of Willow Creek, CA 09:26 UTC
9. 2.5 16km SSE of Somes Bar, CA 11:45 UTC
10. 2.5 8km E of Willow Creek, CA 15:03 UTC
11. 2.0 18km ESE of Willow Creek, CA 04:05 UTC
12. 2.3 20km ENE of Willow Creek, CA 02:35 UTC
13. 2.3 18km E of Willow Creek, CA 16:05 UTC
14. 2.4 12km SE of Weitchpec, CA 08:54 UTC
15. 2.3 15km W of Weaverville, CA 13:26 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 07:47 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.