subduction

"This is the first time we have a clear picture of a subduction zone caught in the act of dying," said Shuck.

When the massive subduction zone lying under the Pacific Northwest shifts, it does so violently.

New research offers the theory that the San Andreas fault and the Cascadia subduction zone could produce devastating back-to-back earthquake disasters.

They are two of the West Coast’s most destructive generators of huge earthquakes: the San Andreas fault in California and the Cascadia subduction zone offshore of California’s North Coast, Oregon, Washington and British Columbia.

Longer seismic ruptures have been found only on subduction megathrusts deep underneath the ocean.