Small aftershock detected in Humboldt County

A small aftershock rumbled near Petrolia Friday evening, a day after a magnitude 7.0 earthquake struck off the coast of Humboldt County and prompted a tsunami warning for the state’s northern coast.

The shock was measured at a magnitude of 3.3 and occurred at about 5 p.m., according to the U.S. Geological Survey.

The USGS reported the quake was located about 22 miles northwest of Petrolia. The quake’s depth was about 8 miles. No injuries or damage were immediately reported.

The earlier 7.0 quake struck at 10:44 a.m. Thursday and was estimated to be a half-mile underneath the Pacific Ocean, about 40 miles off the coast of the town of Ferndale, near the Eel River Valley in humboldt County. The strongest shaking occurred in Ferndale and the small towns of Rio Dell, Fortuna and Petrolia.

The National Tsunami Warning Center issued a tsunami warning at 10:49 a.m. and then canceled it roughly an hour later, at 11:54 a.m.