100 Years of Earthquakes.. 1. April 18, 1906, San Francisco. At 5:12 am on April 18, 1906 there was a major earthquake in San Francisco- a magnitude of 7.8 on the Richter scale.Tremors were felt even in the middle of Nevada, located deep in the continent. As a result of the disaster, almost 80% of the buildings in the city of San Francisco were destroyed and more than 3,000 people died. 2. Dece..