Evison(1977)建立了前兆震群的震级(m_p)与主震震级(m_m)和前兆平静期之间的两种关系。本文选择了缅甸—四川地区进行研究,因为这个地区地震非常活跃。Kaila 和 Narain(1971)研究了该区的地震活动性,并指出,地震活动性的“A”值是6.8-2.4。正如古登堡和里希特(1965)所报道的,该区发生过许多破坏性地震。鉴于地震活动性高和破坏性地震的频繁发生,可以认为该区是研究地震前兆最 Evison (1977) established two relationships between magnitude (m_p) of precursory swarm and magnitude (m_m) of mainshock and precursory quiet period. This paper selects Myanmar - Sichuan area for research, because the earthquake in this area is very active. Kaila and Narain (1971) studied the seismicity of the area and pointed out that the “A” value of seismicity is 6.8-2.4. As Gutenberg and Richter (1965) reported, many devastating earthquakes occurred in the area. In view of the frequent occurrence of high seismic activity and destructive earthquakes, it can be considered that this area is the most sensitive to earthquake precursors