QuakeIndex

Fault · California

Santa Cruz Island fault

67 kmlong (42 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
4quakes 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 7.1 in 1812 (Santa Barbara Channel, California) — about 1,400,000 times the energy of an M3.0, the size people start to feel. It released about 670 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 faultSan Clemente faultSanta Ynez faultSan Gabriel faultSierra Madre faultPitas Point faultCatalina faultOak Ridge fault (offshore)Mission Ridge fault systemSan Pedro Basin faultMalibu Coast faultSanta Cruz faultDume faultOak Ridge faultSimi-Santa Rosa faultSan Cayetano faultMid-Channel faultRed Mountain faultLos Alamos faultVentura faultIsla Vista fault M 7.1 · 1812 · Santa Barbara Channel, California
The Santa Cruz Island fault as mapped at the surface (glowing), with the other mapped faults nearby, 4 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 7.1 Santa Barbara Channel, California
    December 21, 1812 · epicentre 16 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 13 km SSE of Santa Cruz Is. (E end), CA
    2026-05-25 · 7 km from the trace
  2. M 2.7 27 km SSW of Port Hueneme, CA
    2023-07-29 · 9 km from the trace
  3. M 2.6 17km SE of Santa Cruz Is. (E end), CA
    2023-07-07 · 9 km from the trace
  4. M 2.5 21km SE of Santa Cruz Is. (E end), CA
    2020-06-22 · 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.