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.

The public has often thought of these danger zones as separate entities.

But what if they were capable of back-to-back disasters?

That’s the unsettling possibility described in a groundbreaking new study published recently in the journal Geosphere.

The authors suggest that, for thousands of years, large earthquakes on the Cascadia subduction zone were quickly followed by large earthquakes on the northern San Andreas fault.

In 1700, a Cascadia subduction zone earthquake is believed to have measured around a magnitude 9. Based on archaeological evidence, villag

See Full Page