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帕米尔邻近地区（简称西区）的强震活动频度明显高于川滇菱形块体邻近地区（简称东区）。西区发生的地震主要为中、深源地震，而东区发生的地震则全部为浅源地震；西区主要的地震能量在本世纪初释放，而东区在滞后了40余年后在本世纪中叶地震能量开始强释放。东、西两区的强震活动频次呈现准同步盛哀起伏，在50～60年代相继达到高潮，80年代以后两区均趋于相对平静；在时间序列上呈现东、西交替发生的特点，往往是西区先发生强震，然后在东区有相应的强震与之呼应。造成这些特征的原因是由于印度板块向北碰撞俯冲的不均匀性所致。印度板块的北西顶角向亚欧大陆板块插入较深，而北东顶角插入较浅，这种类似于跷跷板的模式，造成了西、东两头中深源地震和浅源地震相继交替发生。
The frequency of strong earthquakes in the vicinity of the Pamir (the western region) is significantly higher than that in the adjacent region of the Sichuan-Yunnan rhombic block (the eastern region for short). The earthquakes in the western region were mainly middle and deep earthquakes, while the earthquakes in the eastern part were all shallow earthquakes. The main seismic energy in the western part of the country was released at the beginning of this century, while the eastern part of the earth started seismic energy more than 40 years later in the middle of this century Strong release. The frequency of strong earthquakes in the eastern and western regions showed quasi-synchronous ups and downs, reaching climax one after another in the 1950s and 1960s, and both regions tended to be relatively calm after the 1980s. In the time series, It is often the case that a strong earthquake first occurred in the western part of the country and a corresponding strong earthquake echoed in the eastern part of the country. The reason for these characteristics is due to the non-uniform subduction of the Indian plate to the north. The northwest apex of India plate is deeper into the Eurasian plate and the northeastern apex is more shallowly inserted. This is similar to the seesaw mode, resulting in the alternating occurrence of deep-source and shallow-source earthquakes in the west and east.