EUREKA (CBS SF) — A swarm of earthquakes ranging in magnitude from 3.2 to 5.6 rattled the floor of the Pacific Ocean near the California-Oregon border Monday, officials said.

The U.S. Geological Survey said the swarm began with a 4.3 magnitude quake at 5:16 a.m. with an epicenter in the fault zones located in the undersea Gorda Ridges located 147 miles northwest of Eureka.

That quake was followed by temblors measuring 5.2, 3.4, 4.3, 3.2, 4.3 and the largest a 5.6 at 7:44 a.m.

The USGS said the quakes did not trigger a tsunami warning for the West Coast including Northern California.