Hidden Earthquake Risks: What Lies Beneath California's Coast?

Deep beneath California's north coast, a seismic puzzle is unfolding.

Scientists have uncovered hidden fault lines, revealing that the earthquake risk in the region might be much higher than we thought. The Mendocino Triple Junction, a hotspot where three tectonic plates meet, is more complex than previously believed.

A Region of Five Moving Plates

Researchers found that this area is actually made up of five moving plates, not three. Two of these plates are hidden beneath the surface, making the region even more unstable. This discovery could have serious implications for the millions of people living nearby.

Tracking Deep Earthquakes

The team used a network of seismometers to track small, deep earthquakes. These tremors are too tiny to feel at the surface but can provide clues about what's happening underground.

The Pioneer Fragment

The study also confirmed the existence of the Pioneer fragment, a leftover piece of an ancient plate that's now being pulled beneath the North American plate.

Shallow Earthquakes and New Discoveries

One surprising finding was that the subducting surface of these plates is not as deep as scientists thought. This could explain why some earthquakes, like the 1992 Humboldt County quake, have shallow origins.

The discovery challenges our understanding of plate boundaries and highlights the need for better earthquake preparedness.