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南迦巴瓦构造结由其核部的喜马拉雅构造单元和周边的冈底斯构造单元、雅鲁藏布构造单元组成。喜马拉雅构造单元为构造楔入体 ,两侧发育有右旋和左旋走滑断层系 ,构成南迦巴瓦楔入构造。由于南迦巴瓦构造结的楔入作用 ,使雅鲁藏布缝合线横推错位 ,形成滇藏涡旋构造 ,并为雅鲁藏布大峡谷的形成奠定了基础。南迦巴瓦楔入构造的形成与印度板块连续的向北汇聚推挤作用发生反时针旋转有关 ,并可分为点碰撞 (45Ma前 )、碰撞楔入 (45~ 7Ma)和旋转抬升 (7Ma以来)三个阶段。
The Namjagbarwa structural knot consists of the Himalayan tectonic units in the core and the Gangdise tectonic units and the Brahmaputra tectonic units in the periphery. The Himalayan tectonic unit is a wedge-shaped body with dextral and left-lateral strike-slip fault systems developed on both sides, forming a wedge structure of Namjagbarwa. Due to the wedging effect of the Namjagbarwa tectonic knot, the Yarlung Zangbu suture was horizontally pushed out of position to form the Yunnan-Tibet vortex structure and laid the foundation for the formation of the Yarlung Zangbo Grand Canyon. The formation of the Namjagbarwa wedge structure is related to the continuous thrusting of the Indian plate to the north in the counterclockwise direction and can be divided into point collision (45Ma ago), collision wedge (45 ~ 7Ma) and rotation uplift (7Ma Since) three stages.