QuakeIndex

Fault · California

San Gabriel fault

135 kmlong (84 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
61quakes of M2.5+ within 10 km since 2016

In plain English

The two sides move 0.2 to 1 mm a year — 2 to 10 cm every century.

Its most recent surface rupture is younger than 15,000 years.

The largest earthquake recorded near it was M 7.5 in 1812 (Northwest of San Bernardino, California) — about 5,600,000 times the energy of an M3.0, the size people start to feel. It released about 2.7 megatons of TNT.

USGS maps it as 5 sections: Big Tujunga section, Honor Rancho section, Newhall section, Palomas section, San Gabriel River section.

This week vs. its last ten years

0/100

quiet

0 quakes of M1.5+ within 5 km of the trace in the last 7 days — busier than 0% of weeks since 2016. A normal week: 0–0.

Computed from the USGS catalogue · a description of the past, not a forecast · method

San Andreas faultElsinore faultGarlock faultSan Jacinto faultNewport-Inglewood-Rose Canyon faultSanta Ynez faultLenwood-Lockhart faultHelendale-South Lockhart faultSierra Madre faultPitas Point faultPalos Verdes faultOak Ridge fault (offshore)Mission Ridge fault systemSan Pedro Basin faultNorth Frontal thrust systemSanta Cruz Island faultHarper faultMalibu Coast faultSanta Cruz faultBlackwater faultDume faultOak Ridge faultSimi-Santa Rosa faultPuente Hills blind thrust systemSan Cayetano faultMid-Channel faultRed Mountain faultSan Gorgonio Pass faultPleito faultSanta Monica faultNorthridge blind thrustWheeler Ridge faultCleghorn faultRaymond faultCrafton Hills faultVerdugo faultMt. General faultHollywood faultVentura faultRed Hill-Etiwanda Avenue faultBeaumont Plain fault M 7.5 · 1812 · Northwest of San Bernardino, California M 6.6 · 1971 · 1971 San Fernando Earthquake, California M 6.4 · 1899 · Cajon Pass area, northwest of San Bernardino, California M 6.2 · 1894 · Northwest of San Bernardino, California M 6.0 · 1855 · Near San Gabriel, California M 6.0 · 1858 · Near San Bernardino, California
The San Gabriel fault as mapped at the surface (glowing), with the other mapped faults nearby, 61 of the M2.5+ earthquakes within 10 km of it since 2016 (dots), and the epicentres of the large historic earthquakes recorded near it (rings). Traces: USGS Quaternary Fault and Fold Database. Historic epicentres are estimates.

Every year since 2016

Earthquakes of M2.5+ with an epicentre within 10 km of the mapped trace. Near is not the same as on: some will have slipped on neighbouring faults.

The big ones recorded near it

  1. M 7.5 Northwest of San Bernardino, California
    December 8, 1812 · epicentre 8 km from the trace
  2. M 6.6 1971 San Fernando Earthquake, California
    February 9, 1971 · epicentre 8 km from the trace
  3. M 6.4 Cajon Pass area, northwest of San Bernardino, California
    July 22, 1899 · epicentre 6 km from the trace
  4. M 6.2 Northwest of San Bernardino, California
    July 30, 1894 · epicentre on the trace
  5. M 6.0 Near San Gabriel, California
    July 11, 1855 · epicentre 11 km from the trace
  6. M 6.0 Near San Bernardino, California
    December 16, 1858 · epicentre 14 km from the trace
  7. M 4.2 1km SE of Sylmar, CA
    July 30, 2020 · epicentre 8 km from the trace
  8. M 4.2 1 km W of Lytle Creek, CA
    January 5, 2024 · epicentre 2 km from the trace

Before 1973 from the USGS ComCat historical catalogue (within 25 km; epicentres of old earthquakes are estimates). Since 2016, M4+ within 10 km.

Most recent near it

  1. M 2.6 9 km SW of Valencia, CA
    2026-08-12 · 8 km from the trace
  2. M 2.7 5 km NNE of Castaic, CA
    2026-04-08 · 5 km from the trace
  3. M 2.8 10 km SSW of Valencia, CA
    2026-02-08 · 8 km from the trace
  4. M 2.5 4 km SE of Lytle Creek, CA
    2026-01-18 · 7 km from the trace
  5. M 2.5 10 km SSW of Valencia, CA
    2025-12-27 · 9 km from the trace
  6. M 2.6 10 km SSW of Valencia, CA
    2025-12-27 · 9 km from the trace

Neighbouring faults

Fault trace, slip rate and age: USGS Quaternary Fault and Fold Database (public domain), simplified for the web. Earthquakes: USGS ComCat. QuakeIndex does not forecast earthquakes; a fault's history describes the past. For early warning use ShakeAlert.