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通过跨越缝合带的综合地球物理和地质调查研究,查明了地质上推测的“班公湖-怒江缝合带”的深部结构和构造,提出了下述观点现有资料尚不足以证明,“班公湖-怒江缝合带”是严格意义上的缝合带,而趋向表明是一个老的弧后拉张区,在后来的印度大陆与拉萨地块碰撞挤压过程中,先是沉积了巨厚的第三纪地层,仅在20Ma(?)以来才转变成挤压体制,形成多条逆冲断裂;纳木错-申扎逆冲的蛇绿岩片带代表着侏罗纪洋的主要缝合带位置,在其闭合过程中洋壳与陆壳一起向北发生俯冲,并形成班戈岩带所代表的岩浆弧,在岩浆弧后出现了拉张区;下地壳向北挤压增厚,物理性质不同的上、下地壳之间相互运动而形成了一条缓倾的剪切片理化带,南北长达300km,命名为主羌塘逆冲断裂带(MQT);并使班戈岩片整体向南逆推上去,致使地壳分层增厚;在拉张期伦坡拉小地块向下运动,20Ma以后转变成压缩体制后又开始向上逆推,再加上后期的剥蚀,致使班戈深成岩体出露于地表;唐古拉山、各拉丹冬等年轻的火山岩浆带与地表显示的构造活动无直接关系,推测应是地壳深层作用引起的构造岩浆活动的显示。
Through comprehensive geophysical and geological investigations across the suture zone, the geotechnically inferred structure and structure of the “Banghu-Nujiang suture zone” has been identified. The available data from the following points of view are not yet sufficient to prove that the “class The ”Gonghu-Nujiang Suture" is a suture in the strict sense of the word, and the trend shows that it is an old arc-pull extension zone. During the later collision and extrusion of the Indian continent and Lhasa block, The Triassic strata changed into a crustal regime only after 20 Ma (?), Forming a number of thrust faults. The Namgou-Shenshan thrust ophiolite belt represents the major suture zone of the Jurassic ocean. During the closure process The mid-oceanic crust and continental crust subducted northward to form the magmatic arc represented by the Bangor belt. After the magma arc, there was a tension zone. The lower crust crushed northwards and thickens with different physical properties, The interaction between the crust and the formation of a gently sloping shear plate physics and chemistry zone, north and south up to 300km, named the main Qiangtang thrust belt (MQT); and the whole rock to the south of Bangle thrust up, causing the crust Stratified thickening; small stretch in the stretch of slope small slope down, 20M After a period of transformation into a compression system, it began to reverse upwards again. Coupled with the later denudation, the Bangeng deep pluton was exposed to the earth’s surface. The young volcanic magma belts and the tectonic activities of the Tanggula and Lhasa Dongdong showed no surface activity Direct relationship, speculated that the tectonic magma activity caused by the deep crustal action.