QuakeIndex

Fault · California

East Monterey Bay fault

24 kmlong (15 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
3quakes 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 6.3 in 1926 (22 km S of Davenport, California) — about 110,000 times the energy of an M3.0, the size people start to feel. It released about 51 kilotons of TNT.

This week vs. its last ten years

Too quiet to rank: fewer than half a year's worth of weeks with any M1.5+ quake within 5 km, in ten years. A single quake here would read as "unusual", so we do not score it.

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

San Andreas faultGreat Valley thrust fault systemSan Gregorio faultCalaveras faultHayward faultGreenville faultMonterey Bay- Tularcitos faultZayante-Vergeles faultOrtigalita faultSargent faultMonte Vista-Shannon faultButano faultPfeiffer Point faultQuien Sabe faultTres Pinos fault M 6.3 · 1926 · 22 km S of Davenport, California M 6.3 · 1890 · East of Watsonville, California M 6.0 · 1899 · Near San Juan Bautista, California
The East Monterey Bay fault as mapped at the surface (glowing), with the other mapped faults nearby, 3 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 6.3 22 km S of Davenport, California
    October 22, 1926 · epicentre 18 km from the trace
  2. M 6.3 East of Watsonville, California
    April 24, 1890 · epicentre 24 km from the trace
  3. M 6.0 Near San Juan Bautista, California
    April 30, 1899 · epicentre 22 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 2.5 1 km SW of Aptos Hills-Larkin Valley, CA
    2026-03-07 · 5 km from the trace
  2. M 2.8 12km W of Moss Landing, CA
    2021-09-29 · 3 km from the trace
  3. M 3.2 12km W of Moss Landing, CA
    2021-09-22 · 3 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.