晚白垩世后青藏高原和塔里木地块的整体北移

NORTHWARD MIGRATION OF THE QINGHAIXIZANG PLATEAU AND TARIM BLOCK SINCE THE LATE CRETACEOUS

本文根据塔里木地块及其以南的昆仑、羌塘和拉萨地块晚中生代特别是晚白垩世古地磁数据,提出青藏高原自晚白垩世后北向移动两千余公里,主要并不是通过它本身的大规模地壳缩短来完成,而是与塔里木地块一起作大规模整体北移的结果。一种可能的解释是,在欧亚大陆北部稳定区和塔里木地块之间广大的中亚构造带,自晚白垩世后发生了大规模的地壳缩短。

The Late Cretaceous paleomagnetic poles for the Tarim, Kunlun, Qiangtang and Lhasa blocks strongly suggest that the northward movement of over 2000 km of the Qinghai-Xizang Pla- teau since Late Cretaceous was not achieved through internal crystal shortening but was caused by large-scale northward migration of the Qinghai-Xizang Plateau and Tarim block with respective to the stable northern Eurasia. One possible interpretation is that the wide range of central-Asia tectonic belt between the north of the Tarim block and the south of the stable northern Eurasia has experienced a large scale crustal shortening since Late Cretaceous.