QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near North Tustin, CA

No earthquake was likely felt in North Tustin in the 24 hours to 5:35 am PST (13:35 UTC). The last one was M 3.2, 36 km (22 mi) W, at 12:44 am PDT on 9 October 2026, estimated intensity II (weak) in town; 1,090 felt reports to USGS. Every earthquake near North Tustin

This page: a magnitude 1.8 earthquake was recorded 6 km (4 mi) east-northeast of North Tustin, CA, at 12:49 am PDT on 17 October 2019 (07:49 UTC), 12 km deep. 1 person has reported feeling it to USGS.

USGS: 6km ENE of North Tustin, CA

7 km (4 mi) SSE of Anaheim, CA · 67 km (42 mi) ESE of Los Angeles, CA

12:49 am PDT, Oct 17, 2019 · · 12 km deep · released about 14 lb of TNT

Every earthquake near North Tustin Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orange County 13 kmLos Angeles County 66 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
12:49 am PDT on 17 October 2019 ()
Where
6 km (4 mi) east-northeast of North Tustin, CA · earthquakes near North Tustin
Magnitude
M 1.8 (ml)
Depth
12 km below the surface
Felt
1 report · strongest reported intensity III
Nearest
Orange County, 13 km SSW
Nearest mapped fault
Elsinore fault, 11 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 2583 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 5 km (3 mi) from the epicentre. In North Tustin, 6 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: Villa Park, Tustin, Orange, Yorba Linda, Santa Ana, Placentia.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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 2018-08-29 — about 7,900 times the energy of this one.

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

  1. 6.4 The 1933 Long Beach, California Earthquake · 30 km SW of this epicentre
  2. 6.0 The 1910 Lake Elsinore, California Earthquake · 33 km ESE of this epicentre
  3. 5.9 The 1987 Whittier Narrows, California Earthquake · 43 km NW of this epicentre
  4. 5.5 The 1990 Upland, California Earthquake · 39 km N of this epicentre
  5. 5.4 5km S of Chino Hills, CA · 18 km N 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 33.7923, -117.7397. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orange County, CA 13 km (8 mi) SSW earthquakes near Orange County
Los Angeles County, CA 66 km (41 mi) NW earthquakes near Los Angeles County
San Diego County, CA 124 km (77 mi) SE earthquakes near San Diego 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. 1.7 4km S of Huntington Beach, CA
  2. 1.6 1km SE of Compton, CA
  3. 1.9 2km NNE of Maywood, CA
  4. 2.9 3km ENE of Brea, CA
  5. 3.2 11km ENE of North Tustin, CA
  6. 2.1 3km NE of Brea, CA
  7. 1.5 4km ENE of Brea, CA
  8. 1.6 3km NNW of Bloomington, CA
  9. 3.2 2km ENE of Brea, CA
  10. 1.7 7km NE of Rancho Cucamonga, CA
  11. 2.4 3km E of Upland, CA
  12. 1.5 5 km SE of Home Gardens, CA
  13. 1.9 6km WSW of Norco, CA
  14. 2.6 3km ENE of Brea, CA
  15. 1.6 3 km SE of Home Gardens, 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.