Series of earthquakes strikes off Oregon, Washington coast; no tsunami threat

A string of five earthquakes with a top magnitude of 5.9 has struck in an area off the Pacific Northwest known for lots of activity along faults but little tsunami danger.

The earthquakes began around midnight Sunday. The latest and most powerful struck at about 1 p.m. Monday.

U.S. Geological Survey scientists say the earthquakes were nearly 300 miles west of Coos Bay, Oregon, in an area that has generated dozens of such quakes in recent decades.

The temblors were shallow, about 6 miles deep, and none of them triggered a tsunami. Geophysicist Paul Caruso says that generally takes a magnitude-7 quake.

Scientists say the area's crustal blocks slide past each other horizontally, creating less violent movement than along faults where blocks rise and fall in relation to each other.