The palaeomagnetic study of the collision and collage of major land-masses in the Nujiang-Lancangjiang-Jinshajiang area in western Yunnan and eastern Xizang

In order to explore the evolution and history of the collision and collage of the major landmasses in the Nujiang-Lancangjiang-Jinshajiang area in western Yunnan and eastern Xizang, the comparative study has been made for the migration of the present-day latitudes and palaeolatitudes of South China, Simao, Baoshan, Burma-Thailand, Indo-China, Lhasa and Himalaya landmasses in the light of the palaeomagnetic data in integration with the existing sedimentary records and palaeogeographic information. The results show that:(1) the Simao landmass may be derived from the South China landmass; (2) the Baoshan and Burma-Thailand landmasses once drifted rapidly northwards during the Late Carboniferous and Late Permian; (3) after the collision with the South China landmass during the Late Permian, the Baoshan landmass continued to drift northwards together with the Burma-Thailand, South China and Indo-China landmasses till the Late Triassic, and (4) the Palaeo-Tethyan Ocean between the Baoshan and South China landmasses might be opened during the Early Silurian and closed during the Late Permian.