QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

Earthquake near Pacheco, CA

No earthquake was likely felt in Pacheco in the 24 hours to 4:07 am PST (12:07 UTC). The last one was M 2.1, 5 km (3 mi) S, at 4:05 am PST on 8 November 2026, estimated intensity II (weak) in town; 3 felt reports to USGS. Every earthquake near Pacheco

This page: a magnitude 2.0 earthquake was recorded in Pacheco, CA, at 11:55 am PST on 3 March 2019 (19:55 UTC), 17 km deep. 1 person has reported feeling it to USGS.

USGS: 1km NNE of Pacheco, CA

6 km (4 mi) WNW of Concord, CA · 39 km (24 mi) NE of San Francisco, CA

11:55 am PST, Mar 3, 2019 · · 17 km deep · released about 26 lb of TNT

10 km30 km60 km120 km N Contra Costa County 13 kmSolano County 32 kmAlameda County 41 kmMarin County 60 kmNapa County 61 kmSan Mateo County 70 kmSan Joaquin County 70 kmYolo County 78 kmSacramento County 81 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
11:55 am PST on 3 March 2019 ()
Where
in Pacheco, CA · earthquakes near Pacheco
Magnitude
M 2.0 (md)
Depth
17 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Contra Costa County, 13 km SE
Nearest mapped fault
Concord fault, 1 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 2804 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. 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.

Earthquakes near other towns within 30 km: Vine Hill, Concord, Pleasant Hill, Martinez, Contra Costa Centre, Waldon.

How big was it?

This earthquake released about 26 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 5.8 580,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 410,000× the energy of this one
  3. Around the size people start to feel M 3.0 36× the energy of this one
  4. This earthquake M 2.0 about 26 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 4,300 times the energy of this one.

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

  1. 6.0 The 2014 South Napa, California Earthquake · 33 km NW of this epicentre
  2. 5.8 The 1980 Livermore, California Earthquake · 31 km ESE of this epicentre
  3. 5.4 South of Elmira, California · 37 km NNE of this epicentre
  4. 5.4 9 km NE of Livermore, California · 42 km SE of this epicentre
  5. 5.1 11 km E of Blackhawk, California · 33 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 37.9942, -122.0675. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Contra Costa County, CA 13 km (8 mi) SE earthquakes near Contra Costa County
Solano County, CA 32 km (20 mi) NNE earthquakes near Solano County
Alameda County, CA 41 km (25 mi) SSE earthquakes near Alameda County
Marin County, CA 60 km (37 mi) W earthquakes near Marin County
Napa County, CA 61 km (38 mi) NNW earthquakes near Napa County
San Mateo County, CA 70 km (43 mi) SSW earthquakes near San Mateo County

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

Aftershocks so far

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

  1. 1.8 2km ENE of Pleasant Hill, CA
  2. 2.2 3km WSW of American Canyon, CA
  3. 1.9 2km NNW of Crockett, CA
  4. 2.4 11km NNE of Napa, CA
  5. 2.1 2km WNW of Vallejo, CA
  6. 2.7 12km NNE of Napa, CA
  7. 2.1 4km WNW of Mountain House, CA
  8. 3.0 6km WNW of Mountain House, CA
  9. 1.6 8km NNW of Bay Point, CA
  10. 1.5 8km NNW of Bay Point, CA
  11. 2.1 4km ENE of Oakland, CA
  12. 2.1 10km NW of Rio Vista, CA
  13. 1.8 5km NW of Mountain House, CA
  14. 1.9 2km NW of Crockett, CA
  15. 2.1 6km SSW of Yountville, 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.