US west coast faults could trigger catastrophic back-to-back earthquakes, study finds

Study shows high-magnitude temblor in north-west could set off another in California, causing unrivaled disaster

Warnings about the looming threat of “the big one” – a catastrophic earthquake that could devastate cities – have stoked fears across the US west coast for decades. But according to a new study, a high-magnitude earthquake in the Pacific north-west could set off a secondary one on California’s San Andreas fault, causing an unrivaled catastrophe.

“The bigger one” would have the potential to wreak havoc up and down the coast at once, researchers say.