QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Redway, CA

No earthquake was likely felt in Redway in the 24 hours to 12:55 am PST (08:55 UTC). The last one was M 5.0, 153 km (95 mi) WNW, at 8:56 pm PST on 4 November 2026, estimated intensity II (weak) in town; 145 felt reports to USGS. Every earthquake near Redway

This page: a magnitude 2.1 earthquake was recorded 19 km (12 mi) north-northeast of Redway, CA, at 7:39 am PDT on 29 June 2018 (14:39 UTC), 27 km deep.

USGS: 19km NNE of Redway, CA

7:39 am PDT, Jun 29, 2018 · · 27 km deep · released about 38 lb of TNT

10 km30 km60 km120 km N Humboldt County 52 kmTrinity County 66 kmMendocino County 96 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
7:39 am PDT on 29 June 2018 ()
Where
19 km (12 mi) north-northeast of Redway, CA · earthquakes near Redway
Magnitude
M 2.1 (md)
Depth
27 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 52 km NNW
Nearest mapped fault
Bartlett Springs fault system, 20 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 3057 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Redway, 19 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 38 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.

  1. Mineral, Virginia 2011 M 5.8 390,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 280,000× the energy of this one
  3. Around the size people start to feel M 3.0 25× the energy of this one
  4. This earthquake M 2.1 about 38 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 4.5 on 2016-08-28 — about 4,300 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.2 The 1992 Petrolia, California Earthquake · 44 km W of this epicentre
  2. 6.0 Near Rio Dell, California · 48 km WNW of this epicentre
  3. 6.0 30 km SSW of Scotia, California · 48 km W of this epicentre
  4. 5.5 7 km ESE of Shelter Cove, California · 38 km SW of this epicentre
  5. 5.4 30 km NW of Shelter Cove, California · 49 km W 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 40.2702, -123.7175. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 52 km (32 mi) NNW earthquakes near Humboldt County
Trinity County, CA 66 km (41 mi) NE earthquakes near Trinity County
Mendocino County, CA 96 km (60 mi) SSE earthquakes near Mendocino County
Glenn County, CA 135 km (84 mi) ESE earthquakes near Glenn County

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

Aftershocks so far

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

  1. 1.9 29km NNE of Redway, CA
  2. 2.5 14km SE of Petrolia, CA
  3. 2.0 34km SW of Hayfork, CA
  4. 2.5 20km SE of Rio Dell, CA
  5. 1.8 7km ENE of Petrolia, CA
  6. 2.4 3km NW of Redway, CA
  7. 1.9 16km SE of Petrolia, CA
  8. 2.0 14km WNW of Hayfork, CA
  9. 2.5 4km SE of Petrolia, CA
  10. 2.7 5km ENE of Petrolia, CA
  11. 1.9 30km SW of Hayfork, CA
  12. 1.9 13km WSW of Rio Dell, CA
  13. 2.1 3km NNE of Redway, CA
  14. 2.5 30km N of Redway, CA
  15. 2.1 9km ENE of Petrolia, 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.