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本文从板块构造的观点出发,根据深大断裂带、蛇绿岩套、混杂堆积、兰闪石片岩的空间分布,在青藏高原地区划分了五条不同时期的板块缝合线。它们从北向南的发展过程是由老到新(加里东至喜山期),其形成的原因是由于洋壳不断的消亡和陆壳不断增生的结果。青藏高原的强震(M_s≥6级)不仅沿板块缝合线成带状分布,还沿它们作往返的迁移,表明强震的分布不仅与年轻的板块缝合线一致,而且也和活动的古板块缝合线一致。根据青藏高原强震分布的特点,提出强震的发生是由于印度板块和欧亚板块的碰撞,其能量的来源与地幔物质的活动有关。而板块缝合线及次一级活动断裂为地震积聚能量提供了条件,起控震作用。
Based on the plate tectonics, five different periods of plate suture are divided in the Qinghai-Tibet Plateau according to the spatial distribution of the deep big fault zone, ophiolite suite, mixed accumulation, and amphibole schist. Their development from north to south was from old to new (Caledonian to Himalayan). The reason for their formation is the result of the continuous demise of oceanic crust and the continual proliferation of continental crust. The strong earthquakes (M_s≥6) in the Qinghai-Tibet Plateau not only distribute along the plate suture but also migrate along them, indicating that the distribution of strong earthquakes is not only consistent with the young plate suture, but also with the active paleo-plate Suture consistent. According to the characteristics of the strong earthquakes in the Qinghai-Tibet Plateau, it is suggested that strong earthquakes occur due to the collision between the Indian plate and the Eurasian plate. The source of energy is related to the activity of the mantle material. The suture line and secondary active faults provide the conditions for seismic energy accumulation and play the role of controlling the earthquake.