QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9md

Earthquake near Paso Robles, CA

No earthquake was likely felt in Paso Robles in the 24 hours to 4:15 am PST (12:15 UTC). The last one was M 2.5, 21 km (13 mi) S, at 11:41 pm PDT on 15 August 2026, estimated intensity II (weak) in town; 61 felt reports to USGS. Every earthquake near Paso Robles

This page: a magnitude 1.9 earthquake was recorded 45 km (28 mi) north-northwest of Paso Robles, CA, at 2:23 am PDT on 1 August 2018 (09:23 UTC), 10 km deep. 1 person has reported feeling it to USGS.

USGS: 3km SSE of San Ardo, CA

2:23 am PDT, Aug 1, 2018 · · 10 km deep · released about 18 lb of TNT

10 km30 km60 km120 km N Monterey County 47 kmSan Benito County 71 kmSan Luis Obispo County 78 kmKings County 97 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
2:23 am PDT on 1 August 2018 ()
Where
45 km (28 mi) north-northwest of Paso Robles, CA · earthquakes near Paso Robles
Magnitude
M 1.9 (md)
Depth
10 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Monterey County, 47 km NW
Nearest mapped fault
San Andreas fault, 22 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 3019 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 10 km (6 mi) from the epicentre. In Paso Robles, 45 km away, the estimate is intensity I (not felt). 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: Lake Nacimiento.

How big was it?

This earthquake released about 18 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 840,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 600,000× the energy of this one
  3. Around the size people start to feel M 3.0 53× the energy of this one
  4. This earthquake M 1.9 about 18 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 14 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 10 km NE of San Simeon, California · 38 km SSW of this epicentre
  2. 6.4 1901 Parkfield, California Earthquake · 35 km E of this epicentre
  3. 6.2 28km NW of Cambria, CA · 50 km SW of this epicentre
  4. 5.8 29 km NE of San Lucas, California · 36 km NNE of this epicentre
  5. 5.8 1934 Parkfield, California Earthquake · 26 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 35.9940, -120.8885. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Monterey County, CA 47 km (29 mi) NW earthquakes near Monterey County
San Benito County, CA 71 km (44 mi) NNW earthquakes near San Benito County
San Luis Obispo County, CA 78 km (49 mi) SSE earthquakes near San Luis Obispo County
Kings County, CA 97 km (60 mi) E earthquakes near Kings County
Fresno County, CA 140 km (87 mi) NE earthquakes near Fresno County
Santa Cruz County, CA 151 km (94 mi) NW earthquakes near Santa Cruz County

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

Aftershocks so far

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

  1. 1.7 24km NE of King City, CA
  2. 1.6 19km SE of Pinnacles, CA
  3. 1.9 23km NW of Parkfield, CA
  4. 2.3 13km N of San Simeon, CA
  5. 1.6 10km SE of New Idria, CA
  6. 2.3 17km NNE of San Simeon, CA
  7. 3.0 24km ENE of San Ardo, CA
  8. 3.3 24km ENE of San Ardo, CA
  9. 1.8 13km N of Cayucos, CA
  10. 1.5 23km ENE of San Lucas, CA
  11. 2.0 25km NW of Parkfield, CA
  12. 1.6 18km NW of Coalinga, CA
  13. 1.6 18km SE of Lopez Point, CA
  14. 2.2 22km ENE of San Lucas, CA
  15. 1.5 10km NNE of Cambria, 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.