QuakeIndex

Fault · California

Foothills fault system

205 kmlong (127 mi), as mapped
not measuredhow fast it slips
last 150 yearssince it last broke the surface
1quakes of M2.5+ within 10 km since 2016

In plain English

It has broken the ground surface within the last 150 years.

The largest earthquake recorded near it was M 4.2 in 2022 (5km S of Oroville East, CA) — about 72 times the energy of an M3.0, the size people start to feel. It released about 35 tons 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 faultHoney Lake faultGreenville faultZayante-Vergeles faultMohawk Valley faultOrtigalita faultWarm Springs Valley faultTahoe-Sierra frontal faultSargent faultWest Tahoe-Dollar Point faultUpper Long Valley faultMonte Vista-Shannon faultAlmanor faultDog Valley faultPolaris faultNorth Tahoe faultPleasanton faultFort Sage faultPeavine Peak faultIndian Valley faultCorral Hollow-Carnegie faultLas Positas fault
The Foothills fault system as mapped at the surface (glowing), with the other mapped faults nearby, 1 of the M2.5+ earthquakes within 10 km of it since 2016 (dots), . 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 4.2 5km S of Oroville East, CA
    July 23, 2022 · 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 4.2 5km S of Oroville East, CA
    2022-07-23 · 2 km from the trace

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.