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印度板块和亚洲大陆的初始碰撞时间是所有相关的喜马拉雅-西藏造山体系演化模式的主控条件,并严重影响到对众多与青藏高原隆升和东亚大陆挤出相关的地质过程速率的解释,以及对新生代全球气候变化的理解。尽管印度板块和亚洲大陆汇聚的速率在55Ma突然减缓被广泛地认为是初始碰撞的标志,但这次碰撞所造成的主要构造效应直到20多个百万年以后才显现出来。对印度板块和亚洲大陆相对位置的重新估算,表明它们在55Ma时并没有达到可以彼此发生碰撞的距离。基于来自西藏新的野外证据和对已有数据的重新评估,认为初始碰撞发生在始新世—渐新世之交(约34Ma),并对55Ma时发生的地质事件提出了另一种解释。
The initial collision time of the Indian Plate and the Asian continent is the dominant condition for the evolution of all related Himalaya-Tibetan orogenic systems and seriously affects the interpretation of a number of geological processes related to the uplift of the Tibetan Plateau and the extrusion of the East Asian continent, as well as Understanding of the Cenozoic Global Climate Change. Although the sudden convergence of the Indian plate and Asian continent at 55 Ma was widely recognized as a sign of initial collisions, the major tectonic effect of the collision did not show up until more than 20 million years ago. The reevaluation of the relative positions of the Indian plate and the Asian continent indicates that they did not reach the point where they could collide with each other at 55 Ma. Based on the new field evidence from Tibet and the reevaluation of the existing data, it is considered that the initial collision occurred at the time of Eocene-Oligocene (about 34 Ma) and suggested another geological event occurred at 55 Ma.