Fault · California
Helendale-South Lockhart fault
Updated , with the latest earthquake of M2.5 or more within 10 km of the trace: M 2.6, 4 km NNW of Big Bear City, CA.
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.
USGS maps it as 3 sections: Helendale section, Northern San Bernardino Mountains section, South Lockhart section.
This week vs. its last ten years
0/100
quiet
No quakes of M1.5+ within 5 km of the trace in the last 7 days. A normal week: 0–1.
Computed from the USGS catalogue · a description of the past, not a forecast · method
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.
Most recent near it
- M 2.6 4 km NNW of Big Bear City, CA
2026-10-06 · 5 km from the trace - M 2.6 7 km ENE of Big Bear City, CA
2025-12-19 · 1 km from the trace - M 2.8 3 km N of Big Bear City, CA
2025-11-01 · 4 km from the trace - M 2.6 7 km N of Big Bear City, CA
2025-10-05 · 3 km from the trace - M 2.5 7 km N of Big Bear City, CA
2025-10-05 · 3 km from the trace - M 3.5 7 km N of Big Bear City, CA
2025-10-05 · 3 km from the trace
Neighbouring faults
- Lenwood-Lockhart fault 3 km away
- North Frontal thrust system 7 km away
- Old Woman Springs fault 11 km away
- Johnson Valley fault 17 km away
- Harper fault 21 km away
- Mt. General fault 22 km away
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.