QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

Earthquake near Big Bear Lake, CA

No earthquake was likely felt in Big Bear Lake in the 24 hours to 4:37 am PST (12:37 UTC). The last one was M 2.6, 7 km (4 mi) NE, at 1:40 am PDT on 6 October 2026, estimated intensity III (weak) in town; 18 felt reports to USGS. Every earthquake near Big Bear Lake

This page: a magnitude 2.7 earthquake was recorded 5 km (3 mi) north of Big Bear Lake, CA, at 8:46 am PST on 9 January 2020 (16:46 UTC), 9.0 km deep. 14 people have reported feeling it to USGS.

USGS: 5km N of Big Bear Lake, CA

30 km (19 mi) NE of Highland, CA · 140 km (87 mi) ENE of Los Angeles, CA

8:46 am PST, Jan 9, 2020 · · 9.0 km deep · released about 340 lb of TNT

Every earthquake near Big Bear Lake Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Bernardino County 92 kmOrange County 104 kmRiverside County 105 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
8:46 am PST on 9 January 2020 ()
Where
5 km (3 mi) north of Big Bear Lake, CA · earthquakes near Big Bear Lake
Magnitude
M 2.7 (ml)
Depth
9.0 km below the surface
Felt
14 reports · strongest reported intensity III
Nearest
San Bernardino County, 92 km NE
Nearest mapped fault
Helendale-South Lockhart fault, 9 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 758 days ago

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 23 km (14 mi) from the epicentre. In Big Bear Lake, 5 km away, the estimate is intensity III (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: Big Bear Lake 5 km, intensity III · Big Bear City 8 km, intensity III · Lucerne Valley 18 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 340 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.8× the energy of this one
  4. This earthquake M 2.7 about 340 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 2018-05-08 — about 480 times the energy of this one.

Before 2016, the USGS record lists 24 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.3 The 1992 Landers, California Earthquake · 45 km ESE of this epicentre
  2. 6.3 The 1992 Big Bear, California Earthquake · 13 km SE of this epicentre
  3. 6.2 3 km SE of San Bernardino, California · 38 km SW of this epicentre
  4. 6.0 The 1986 North Palm Springs, California Earthquake · 43 km SE of this epicentre
  5. 5.6 7km ENE of Running Springs, CA · 12 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 34.2895, -116.9195. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Bernardino County, CA 92 km (57 mi) NE earthquakes near San Bernardino County
Orange County, CA 104 km (65 mi) SW earthquakes near Orange County
Riverside County, CA 105 km (65 mi) SE earthquakes near Riverside County

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

Aftershocks so far

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

  1. 1.7 10km NE of Big Bear City, CA
  2. 1.6 10km NE of Big Bear City, CA
  3. 2.3 5km SE of Loma Linda, CA
  4. 1.5 40km WSW of Ludlow, CA
  5. 2.9 10km NE of Big Bear City, CA
  6. 1.7 10km NE of Big Bear City, CA
  7. 2.4 10km NE of Big Bear City, CA
  8. 1.8 3km SE of Loma Linda, CA
  9. 1.8 16 km NNE of Apple Valley, CA
  10. 1.9 8km NE of Cabazon, CA
  11. 2.1 6km NNW of Big Bear Lake, CA
  12. 1.7 3km SSW of Big Bear City, CA
  13. 1.7 2km WNW of Muscoy, CA
  14. 1.6 2km S of Highland, CA
  15. 1.8 11km NNW of Big Bear Lake, 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.