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通过对强震重复发生的滇西北、滇东北、滇西南澜沧江以西３个地震区多项地震活动性和地震波参数的动态追踪，发现在同一地震区重复发生的强震，震前的异常形态可以具有相似性，也可以出现反向变化的特征。如滇东北地震区中小地震在１９８５年禄劝强震前的活跃和１９９５年武定强震前的平静；澜沧地震台单台波速比月均值在１９８８年澜沧—耿马大震前的低值异常和１９９５年孟连西中缅边境大震前的高值异常。本文同时以ｂ值和波速比为例，讨论了强震成组发生时强震所在的地震区和未发生强震的地震区各自不同的变化特征。结果表明：发生了强震的地震区，在强震前２—８年，ｂ值均出现高达１．８０的突变异常，而未发生强震的滇西地震区ｂ值最大值为１．５０，从而提出了中长期源兆的问题；同样，单台波速比在强震震中附近的台站，其高值突变的幅度要比远离强震震中的台站大２０—６０％。
Through the dynamic tracking of seismic activity and seismic wave parameters in 3 seismic districts in northwestern Yunnan, northeastern Yunnan and western Lancang River, where strong earthquakes occur repeatedly, it is found that the strong anomalies that occurred repeatedly in the same earthquake area can be With similarities, but also can appear the characteristics of the reverse change. Such as the earthquake in northeastern Yunnan earthquake in 1985 before the Luquan strong earthquakes and the 1995 Wuding earthquake before the calm; Lancang seismic station a single wave velocity ratio of the monthly average in 1988 before the Lancang - Gengma earthquake low anomalies and High-value anomalies before the great earthquake of the Sino-Burmese border in 1995. In this paper, taking the b value and the wave velocity ratio as an example, we discuss the different changing characteristics of the earthquake area where strong earthquakes occur and the earthquakes that do not occur when strong earthquakes occur. The results show that in the earthquake area where strong earthquakes occurred, the abnormal value of b was up to 1.80 in the two to eight years before the strong earthquakes, while the maximum value of b in the west Yunnan Earthquake without any strong earthquakes was 1.50 , And raised the issue of medium- and long-term source. Similarly, a station with a single wave velocity ratio near the epicenter of a strong earthquake abruptly has a 20-60% larger amplitude than a station far away from the epicenter of strong earthquakes.