近(near)震震级或地方性震级,也有称区域性(regional)地震震级。一般指震中距2000Km以内的地震而言。由于地区性结构的差别,近震震级不能像远震震级那样建立全球性的统一标度。1935年Richter在南加利福尼亚引入的近震震级标度M_L,作为原始的震级标度。世界其它地区再根据本区域的特征建立本区域的近震震级标度,这种标度必须通过某种 Near earthquake magnitude or local magnitude, also known as regional earthquake magnitude. Generally refers to the epicenter of earthquakes in the distance 2000Km terms. Due to the difference in regional structure, the near-Earthquake magnitude can not establish a global unified scale like the magnitude of a long-distance earthquake. 1955 Richter introduced in southern California near epicenter scale M_L, as the original magnitude scale. In the rest of the world, the magnitude of the near earthquakes in the region is again established on the basis of the characteristics of the region,