Archive · 28 Jan 2026
Hidden Faults Found in California Earthquake Hotspot
Scientists have found hidden faults under Northern California.
They studied tiny earthquakes to map these faults, which are under the ground.
They discovered that there are five moving pieces of Earth's crust instead of three.
This helps explain why a big earthquake happened in 1992.
Understanding these hidden faults is important for predicting future earthquakes and keeping people safe.
Scientists discovered hidden fault structures beneath Northern California's Mendocino Triple Junction.
The region is a complex earthquake zone where three major tectonic plates meet.
Researchers found five interacting tectonic plates, including two hidden fragments.
The study used low-frequency microquakes to map the hidden faults.
The findings help explain the 1992 magnitude 7.2 earthquake and improve seismic hazard forecasts.
- Who
- Researchers from the US Geological Survey, UC Davis, and University of Colorado Boulder
- What
- Discovery of hidden fault structures beneath Northern California
- When
- Study published on January 15
- Where
- Mendocino Triple Junction, off the coast of Humboldt County, Northern California
- Why
- To better understand and predict seismic hazards in the region
- Location
- Mendocino Triple Junction, off the coast of Humboldt County, Northern California
- Key Findings
- Five tectonic plates interacting, including two hidden fragments
- Research Method
- Analysis of low-frequency microquakes
- Significance
- Improves understanding of seismic hazards in the region
- Publication Date
- January 15
- Researchers
- US Geological Survey, UC Davis, University of Colorado Boulder
- Notable Earthquake
- 1992 magnitude 7.2 earthquake