QuakeIndex

Fault · California

Pleasanton fault

19 kmlong (12 mi), as mapped
not measuredhow fast it slips
< 15,000 yearssince it last broke the surface
134quakes of M2.5+ within 10 km since 2016

In plain English

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

The largest earthquake recorded near it was M 6.8 in 1868 (The 1868 Hayward Fault, California Earthquake) — about 500,000 times the energy of an M3.0, the size people start to feel. It released about 240 kilotons of TNT.

This week vs. its last ten years

89/100

elevated

2 quakes of M1.5+ within 5 km of the trace in the last 7 days — busier than 89% of weeks since 2016. A normal week: 0–1.

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

San Andreas faultGreat Valley thrust fault systemSan Gregorio faultFoothills fault systemCalaveras faultHayward faultGreenville faultZayante-Vergeles faultOrtigalita faultRodgers Creek faultSargent faultMonte Vista-Shannon faultButano faultWest Napa faultBennett Valley faultGreen Valley faultConcord faultCordelia faultSerra faultCorral Hollow-Carnegie faultLas Positas fault M 6.8 · 1868 · The 1868 Hayward Fault, California Earthquake M 6.2 · 1858 · North of San Jose, California M 6.0 · 1864 · Alameda County, California
The Pleasanton fault as mapped at the surface (glowing), with the other mapped faults nearby, 134 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 6.8 The 1868 Hayward Fault, California Earthquake
    October 21, 1868 · epicentre 15 km from the trace
  2. M 6.2 North of San Jose, California
    November 26, 1858 · epicentre 20 km from the trace
  3. M 6.0 Alameda County, California
    March 5, 1864 · epicentre 13 km from the trace
  4. M 4.2 4 km SE of San Ramon, CA
    February 2, 2026 · epicentre on 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 3.6 3 km SW of Alamo, CA
    2026-06-07 · 8 km from the trace
  2. M 2.8 3 km ESE of San Ramon, CA
    2026-03-24 · 0 km from the trace
  3. M 2.7 3 km ESE of San Ramon, CA
    2026-03-23 · 0 km from the trace
  4. M 2.8 4 km SE of San Ramon, CA
    2026-03-13 · 1 km from the trace
  5. M 2.6 5 km SE of San Ramon, CA
    2026-03-08 · 1 km from the trace
  6. M 2.6 3 km ESE of San Ramon, CA
    2026-03-08 · 0 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.