QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6md

Earthquake near Dublin, CA

No earthquake was likely felt in Dublin in the 24 hours to 8:16 am PST (16:16 UTC). The last one was M 1.9, 5 km (3 mi) SW, at 10:32 am PST on 2 November 2026, estimated intensity II (weak) in town. Every earthquake near Dublin

This page: a magnitude 1.6 earthquake was recorded 5 km (3 mi) southwest of Dublin, CA, at 5:22 pm PST on 31 December 2018 (01:22 UTC), 9.4 km deep.

USGS: 5km SW of Dublin, CA

8 km (5 mi) NNE of Union City, CA · 44 km (27 mi) NNW of San Jose, CA

5:22 pm PST, Dec 31, 2018 · · 9.4 km deep · released about 8.7 lb of TNT

10 km30 km60 km120 km N Alameda County 7 kmContra Costa County 28 kmSan Mateo County 45 kmSanta Clara County 56 kmSolano County 66 kmSan Joaquin County 69 kmSanta Cruz County 73 kmMarin County 79 kmStanislaus County 87 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
5:22 pm PST on 31 December 2018 ()
Where
5 km (3 mi) southwest of Dublin, CA · earthquakes near Dublin
Magnitude
M 1.6 (md)
Depth
9.4 km below the surface
Felt
no reports yet
Nearest
Alameda County, 7 km ESE
Nearest mapped fault
Calaveras fault, 5 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 2806 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 7 km (4 mi) from the epicentre. In Dublin, 5 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: Dublin 5 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 8.7 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.7 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 13,000 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. 6.2 Near San Jose, California · 44 km SSE of this epicentre
  2. 6.2 The 1984 Morgan Hill, California Earthquake · 48 km SE of this epicentre
  3. 5.8 The 1980 Livermore, California Earthquake · 27 km NE of this epicentre
  4. 5.7 15 km NE of East Foothills, California · 34 km SE of this epicentre
  5. 5.5 6 km NNE of East Foothills, California · 32 km SE 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 37.6703, -121.9828. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alameda County, CA 7 km (4 mi) ESE earthquakes near Alameda County
Contra Costa County, CA 28 km (17 mi) N earthquakes near Contra Costa County
San Mateo County, CA 45 km (28 mi) SW earthquakes near San Mateo County
Santa Clara County, CA 56 km (35 mi) SSE earthquakes near Santa Clara County
Solano County, CA 66 km (41 mi) N earthquakes near Solano County
San Joaquin County, CA 69 km (43 mi) ENE earthquakes near San Joaquin County

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

Aftershocks so far

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

  1. 1.7 2km NNW of San Leandro, CA
  2. 1.7 3km WNW of Diablo, CA
  3. 1.5 3km S of Loyola, CA
  4. 2.3 8km E of Alum Rock, CA
  5. 1.7 11km SE of Livermore, CA
  6. 2.5 4km WSW of Colma, CA
  7. 1.8 2km E of Berkeley, CA
  8. 1.6 5km SW of Pacheco, CA
  9. 2.7 3km NNE of San Ramon, CA
  10. 2.4 1km N of Vine Hill, CA
  11. 2.8 3km NE of Oakland, CA
  12. 2.4 17km ESE of Livermore, CA
  13. 1.8 8km SSE of Portola Valley, CA
  14. 2.0 1km NNE of Pacheco, CA
  15. 1.5 3km ESE of Berkeley, 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.