The U.S. Geological Survey is explaining why more than 64-thousand Mendocino County residents were told to brace for a larger earthquake than actually hit. At 11:20 Sunday night, smart phone users got an alert telling them to brace for a magnitude 4.7 earthquake. It also said “drop, cover and hold on.” But, it ended up being a 3.5 earthquake centered about 12 miles east of Cloverdale. Officials say their ground sensor was actually too close to the epicenter of the earthquake, causing the sensor to pick up primary and secondary waves at the same time. The system likely got confused into thinking the quake was larger.
Smaller Earthquake Than Expected Recorded in Mendocino County
