QuakeIndex

Earthquake · reviewed by a seismologist

M 2.0md

Earthquake near Aromas, CA

No earthquake was likely felt in Aromas in the 24 hours to 5:57 am PST (13:57 UTC). The last one was M 2.0, 11 km (7 mi) SE, at 2:11 am PST on 11 November 2026, estimated intensity II (weak) in town. Every earthquake near Aromas

This page: a magnitude 2.0 earthquake was recorded 5 km (3 mi) east-southeast of Aromas, CA, at 12:24 pm PDT on 12 August 2018 (19:24 UTC), 5.1 km deep. 4 people have reported feeling it to USGS.

USGS: 5km ESE of Aromas, CA

52 km (32 mi) SSE of San Jose, CA · 16 km (10 mi) S of Gilroy, CA

12:24 pm PDT, Aug 12, 2018 · · 5.1 km deep · released about 26 lb of TNT

10 km30 km60 km120 km N Santa Cruz County 40 kmSanta Clara County 41 kmSan Benito County 53 kmMonterey County 74 kmMerced County 86 kmAlameda County 91 kmSan Mateo County 92 kmStanislaus County 94 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
12:24 pm PDT on 12 August 2018 ()
Where
5 km (3 mi) east-southeast of Aromas, CA · earthquakes near Aromas
Magnitude
M 2.0 (md)
Depth
5.1 km below the surface
Felt
4 reports · strongest reported intensity III
Nearest
Santa Cruz County, 40 km WNW
Nearest mapped fault
San Andreas fault, 2 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 3008 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 15 km (9 mi) from the epicentre. In Aromas, 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: Prunedale 12 km, intensity II. Estimated for each town centre; each link is that town's own record.

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 4.6 on 2017-11-13 — about 8,500 times the energy of this one.

Before 2016, the USGS record lists 28 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.9 The 1989 Loma Prieta, California Earthquake · 32 km NW of this epicentre
  2. 6.5 Near Morgan Hill, California · 28 km N of this epicentre
  3. 6.1 Near San Jose, California · 42 km NNW of this epicentre
  4. 5.9 10 km SE of Tres Pinos, California · 36 km ESE of this epicentre
  5. 5.8 Near Watsonville, California · 13 km NW 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 36.8650, -121.5937. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Santa Cruz County, CA 40 km (25 mi) WNW earthquakes near Santa Cruz County
Santa Clara County, CA 41 km (25 mi) NNW earthquakes near Santa Clara County
San Benito County, CA 53 km (33 mi) ESE earthquakes near San Benito County
Monterey County, CA 74 km (46 mi) SSE earthquakes near Monterey County
Merced County, CA 86 km (53 mi) ENE earthquakes near Merced County
Alameda County, CA 91 km (57 mi) NNW earthquakes near Alameda County

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

Aftershocks so far

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

  1. 1.6 15km NW of Pinnacles, CA
  2. 1.5 6km NNW of Pinnacles, CA
  3. 1.6 14km SSE of Tres Pinos, CA
  4. 1.7 11km S of Tres Pinos, CA
  5. 3.8 5km SW of Tres Pinos, CA
  6. 2.2 12km NW of Pinnacles, CA
  7. 1.6 9km SSW of Tres Pinos, CA
  8. 1.5 8km E of Chualar, CA
  9. 1.5 7km NW of Pinnacles, CA
  10. 2.4 8km SSE of San Juan Bautista, CA
  11. 1.7 22km NNE of Morgan Hill, CA
  12. 1.7 10km NW of Pinnacles, CA
  13. 2.7 10km NW of Pinnacles, CA
  14. 1.6 14km E of Seven Trees, CA
  15. 1.7 8km ENE of Gilroy, 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.