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 12:20 pm PST (20:20 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 50 km (31 mi) west-northwest of Paso Robles, CA, at 5:27 pm PDT on 15 April 2018 (00:27 UTC), 7.7 km deep.

USGS: 22km N of San Simeon, CA

5:27 pm PDT, Apr 15, 2018 · · 7.7 km deep · released about 21 lb of TNT

Every earthquake near Paso Robles Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Monterey County 46 kmSan Luis Obispo County 83 kmSan Benito County 86 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
5:27 pm PDT on 15 April 2018 ()
Where
50 km (31 mi) west-northwest of Paso Robles, CA · earthquakes near Paso Robles
Magnitude
M 1.9 (md)
Depth
7.7 km below the surface
Felt
no reports yet
Nearest
Monterey County, 46 km NNW
Nearest mapped fault
San Gregorio fault, 17 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 3124 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 13 km (8 mi) from the epicentre. In Paso Robles, 50 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 21 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 5.8 710,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 500,000× the energy of this one
  3. Around the size people start to feel M 3.0 45× the energy of this one
  4. This earthquake M 1.9 about 21 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 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.5 10 km NE of San Simeon, California · 17 km SSE of this epicentre
  2. 6.2 28km NW of Cambria, CA · 20 km SW of this epicentre
  3. 5.8 1934 Parkfield, California Earthquake · 46 km E of this epicentre
  4. 5.7 Southwest of Cambria, California · 39 km S of this epicentre
  5. 5.2 26km NNW of Lake Nacimiento, CA · 21 km NE 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 35.8457, -121.1712. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Monterey County, CA 46 km (28 mi) NNW earthquakes near Monterey County
San Luis Obispo County, CA 83 km (51 mi) SE earthquakes near San Luis Obispo County
San Benito County, CA 86 km (53 mi) N earthquakes near San Benito County

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

Aftershocks so far

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

  1. 1.7 6km W of Templeton, CA
  2. 1.9 10km NE of Cayucos, CA
  3. 1.5 13km NE of San Simeon, CA
  4. 1.8 3km SSE of San Ardo, CA
  5. 1.9 3km SSE of San Ardo, CA
  6. 2.2 3km SE of San Ardo, CA
  7. 1.9 3km SSE of San Ardo, CA
  8. 2.2 10km NE of San Simeon, CA
  9. 1.6 10km ENE of San Simeon, CA
  10. 1.6 16km S of Lake Nacimiento, CA
  11. 1.9 3km SSE of San Ardo, CA
  12. 1.7 3km SSE of San Ardo, CA
  13. 1.5 11km NE of San Simeon, CA
  14. 1.7 17km NW of San Simeon, CA
  15. 1.6 12km NE of San Simeon, 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.