Earthquake · reviewed by a seismologist
M 1.7md
Earthquake near Gustine, CA
No earthquake was likely felt in Gustine in the 24 hours to 2:25 am PST (10:25 UTC). The last one was M 3.1, 23 km (14 mi) WSW, at 9:18 pm PDT on 21 October 2026, estimated intensity II (weak) in town; 9 felt reports to USGS. Every earthquake near Gustine
This page: a magnitude 1.7 earthquake was recorded 28 km (17 mi) southwest of Gustine, CA, at 10:42 pm PDT on 18 May 2020 (05:42 UTC), 2.3 km deep.
USGS: 28km SW of Gustine, CA
53 km (33 mi) ESE of San Jose, CA · 31 km (19 mi) ENE of Gilroy, CA
- When
- 10:42 pm PDT on 18 May 2020 ()
- Where
- 28 km (17 mi) southwest of Gustine, CA · earthquakes near Gustine
- Magnitude
- M 1.7 (md)
- Depth
- 2.3 km below the surface
- Felt
- no reports yet
- Nearest
- Santa Clara County, 40 km WNW
- Nearest mapped fault
- Ortigalita fault, 8 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 2360 days ago
Earthquake alerts for Gustine, CA
Get a notification in this browser when USGS records an earthquake near Gustine, CA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 12 km (7 mi) from the epicentre. In Gustine, 28 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.
Earthquakes near other towns within 30 km: Gilroy.
How big was it?
This earthquake released about 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
- Around the size people start to feel M 3.0 92× the energy of this one
- This earthquake M 1.7 about 10 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 4.2 on 2016-07-19 — about 6,200 times the energy of this one.
Before 2016, the USGS record lists 20 earthquakes of M5 or more within 50 km; the five largest:
- 6.5 Near Morgan Hill, California · 34 km W of this epicentre
- 6.2 The 1984 Morgan Hill, California Earthquake · 43 km WNW of this epicentre
- 6.1 Near San Jose, California · 49 km WNW of this epicentre
- 5.9 10 km SE of Tres Pinos, California · 42 km S of this epicentre
- 5.8 Near Watsonville, 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 37.1125, -121.2582. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Santa Clara County, CA | 40 km (25 mi) | WNW | earthquakes near Santa Clara County |
| Merced County, CA | 48 km (30 mi) | E | earthquakes near Merced County |
| Stanislaus County, CA | 55 km (34 mi) | NNE | earthquakes near Stanislaus County |
| San Benito County, CA | 58 km (36 mi) | SSE | earthquakes near San Benito County |
| Santa Cruz County, CA | 67 km (42 mi) | W | earthquakes near Santa Cruz County |
| Alameda County, CA | 83 km (52 mi) | NW | earthquakes near Alameda County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
58 earthquakes have been recorded within 50 km since this one.
- 1.6 16km ESE of Alum Rock, CA
- 1.6 16km E of Seven Trees, CA
- 2.1 2km SW of Ridgemark, CA
- 2.1 6km E of Tres Pinos, CA
- 1.5 7km SSW of Ridgemark, CA
- 2.2 9km SSW of Tres Pinos, CA
- 2.1 7km SSW of Ridgemark, CA
- 1.8 7km SSW of Ridgemark, CA
- 2.6 2km SW of Ridgemark, CA
- 1.9 4km WSW of Hollister, CA
- 1.8 7km SSW of Ridgemark, CA
- 1.9 11km S of Tres Pinos, CA
- 1.7 14km N of Morgan Hill, CA
- 2.1 10km SSW of Ridgemark, CA
- 1.9 5km NE of Tres Pinos, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.