QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

Earthquake near Bayside, CA

No earthquake was likely felt in Bayside in the 24 hours to 8:28 pm PST (04:28 UTC). The last one was M 5.0, 137 km (85 mi) WSW, at 8:56 pm PST on 4 November 2026, estimated intensity II (weak) in town; 145 felt reports to USGS. Every earthquake near Bayside

This page: a magnitude 2.0 earthquake was recorded 48 km (30 mi) southeast of Bayside, CA, at 12:27 am PDT on 23 August 2019 (07:27 UTC), 23 km deep.

USGS: 35km W of Hayfork, CA

12:27 am PDT, Aug 23, 2019 · · 23 km deep · released about 33 lb of TNT

10 km30 km60 km120 km N Humboldt County 31 kmTrinity County 41 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
12:27 am PDT on 23 August 2019 ()
Where
48 km (30 mi) southeast of Bayside, CA · earthquakes near Bayside
Magnitude
M 2.0 (md)
Depth
23 km below the surface
Felt
no reports yet
Nearest
Humboldt County, 31 km WNW
Nearest mapped fault
Little Salmon fault, 24 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 2633 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 Bayside, 48 km away, the estimate is intensity I (not felt). 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 33 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.0 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 450,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 320,000× the energy of this one
  3. Around the size people start to feel M 3.0 29× the energy of this one
  4. This earthquake M 2.0 about 33 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 4.8 on 2016-07-21 — about 15,000 times the energy of this one.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.4 The 1954 Eureka-Arcata, California Earthquake · 37 km NW of this epicentre
  2. 5.8 Near Eureka, California · 41 km WNW of this epicentre
  3. 5.6 15 km SW of Burnt Ranch, California · 13 km N of this epicentre
  4. 5.4 3 km NNW of Burnt Ranch, California · 28 km NNE of this epicentre
  5. 5.0 2 km E of Rio Dell, California · 43 km WSW 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 40.5990, -123.5927. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humboldt County, CA 31 km (19 mi) WNW earthquakes near Humboldt County
Trinity County, CA 41 km (25 mi) E earthquakes near Trinity County
Tehama County, CA 127 km (79 mi) ESE earthquakes near Tehama County
Siskiyou County, CA 141 km (88 mi) NE earthquakes near Siskiyou County
Glenn County, CA 150 km (93 mi) SE earthquakes near Glenn County

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

Aftershocks so far

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

  1. 2.9 32km SSW of Hayfork, CA
  2. 2.1 7km SE of Willow Creek, CA
  3. 1.8 10km NE of Hydesville, CA
  4. 2.3 26km WSW of Hayfork, CA
  5. 1.8 19km E of Willow Creek, CA
  6. 1.9 3km NE of Hydesville, CA
  7. 1.8 3km NE of Hydesville, CA
  8. 1.9 4km NE of Hydesville, CA
  9. 1.8 25km N of Redway, CA
  10. 2.6 22km E of Petrolia, CA
  11. 1.9 6km N of Hayfork, CA
  12. 2.2 18km E of Willow Creek, CA
  13. 2.3 36km SSW of Hayfork, CA
  14. 1.6 31km WSW of Hayfork, CA
  15. 2.0 20km SSE of Rio Dell, 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.