usgs-quake-map1A strong 6.9 magnitude earthquake struck off the Northern California coast Sunday night, with shaking felt as far away as San Francisco according to one KCBS listener, but so far, there are no reports of damage, and no risk of a tsunami. The quake was centered 50 miles off the coast from Eureka, along the San Andreas fault, about four miles below the sea floor. The initial magnitude was reported at 7.0 and then was later revised down. Several aftershocks, some as powerful as 4.6 magnitude, have been hitting the region. Some are centered inland, and could cause more damage than the original quake. MORE