Cat modeller AIR Worldwide provides analysis

A moderate earthquake has struck off the coast of northern California, breaking windows and cutting power to more than 25,000 households. Catastrophe risk modelling firm AIR Worldwide said little structural damage has been reported and only minor injuries occurred.

The quake had a magnitude of 6.5 and a depth of 13.5 miles. The epicentre was 27 miles west of the town of Ferndale (est. pop. 1,500) and 33 miles west southwest of Eureka, the seat of Humboldt county (est. pop. 26,000). At least a dozen aftershocks have been recorded, the largest of which was M4.4. The last significant earthquake to occur in this area was a M7.2 quake in April 1992.

Earthquake insurance penetration, particularly for residential properties – remain low in California. That, and the fact that the quake occurred along a relatively sparsely populated stretch of California, will limit insured losses from this event, according to AIR.

According to AIR, residential construction in the affected region is dominated by wood frame, as is Ferndale's historic downtown. There is one report of a wood frame house in Eureka having been knocked off its foundation; otherwise the bulk of the damage seems to have been limited to non-structural elements and contents.

AIR will continue to analyse seismological information and damage for this event and additional information will be provided if warranted.