1935年Richthter提出了一种利用地震仪器标度地震强度的方法。那时期在美国南加利福尼亚地区普遍设置了一种Wood-Anderson地震仪(以下简称“W—A仪”),Richter为了对该区的地震进行分类,使用了1932年1月的一个震群的仪器记录资料,作出logB—Δ(B为仪器记录振幅,Δ为震中距)曲线后,发现通过各个地震连成的曲线,基本上是平 In 1935 Richthter proposed a method of using seismic instruments to scale seismic intensity. During that time, a Wood-Anderson seismograph (hereinafter referred to as “W-A instrument”) was commonly installed in the southern United States of America. In order to classify the earthquake in this area, Richter used an earthquake swarm instrument in January 1932 Record data, make logB-Δ (B is the amplitude of the instrument record, Δ is the epicentral distance) curves, and found that the curve formed by each earthquake is basically flat