【摘要】 在前人古地磁工作的基础上,以亚东—格尔木地学断面走廊域为主,补充了29个古地磁新数据。本文根据这些资料,初步研究了青藏高原主要地体演化规律,同时对有关的雅鲁藏布江缝合带、班公湖-怒江缝合带及安多—丁青断裂进行了古地磁学分析和论证。根据古地磁数据,极移曲线的特征及综合前述几个缝合带的讨论,编绘了青藏高原地体演化模式图。本文就青藏高原的活动构造及隆升机制等地质问题也进行了简要分析。更多还原

【Abstract】 Based on 29 sets of new paleomagnetic data from Paleozoic and Mesoz-oic main terranes in Xizang plateau and data of other writers. Some geological problems related to Xizang plateau, such as paleogeographic distributions, boundary between the terranes, collision time of terranes, active tectonic and swell mechanism, etc., have been analyzed and discussed, and the terranes evolution pattern has also tentatively been established. The pattern is that Himalaya, Gandise, Qiangtag and Kunlun terranes had been located in sourthern latitude during Paleozoic era. Overall, Xizang plateau has shown a tendency to move from south to north since Paleozoic era and Qiangtag and Bayanhar terrane had been accreted to southern and northern Kunlun terr-ane from late Triassic epoch to early Jurassic epoch, Gandise terrane to Qiangtang terrane from late Jurassic epoch to early Cretaceous epoch, and Himalaya to Gangdise terrane from late Cretaceous epoch to early Paleog-ene period. Thus these terranes made a unified continent. It responds to the uninterrupted process of accretion of Eurasia. The important mechanism that Xizang Plateau swelled is an intensely intercontinent reduction produced by many terranes on northern Xizang after Cretaceous period.更多还原