岩石圈深层扩张与青藏高原隆升——岩石圈深层扩张模式初论

DEEP-LEVEL EXPANSION OF THE LITHOSPHERE AND UPLIFT OF THE QINGHAI-TIBET PLATEAU——A DISCUSSION OF THE LITHOSPHERE DEEP-LEVEL EXPANSION MODEL

在综述有关青藏高原隆升的各种观点和模式后,依据青藏高原新生代变形和岩石圈组构特征,提出了高原隆升的新的动力学模式——岩石圈深层扩张模式。其基本观点是强调由于印度板块向欧亚板块的强烈俯冲造成岩石圈组构和变形的不均一性及岩石圈中存在的碰撞→收缩(重力不均衡)→伸展(均衡调整)的正向转变和由伸展→收缩的逆向转变的反复交替。据此将青藏高原的造山带划分为三种成因类型:喜马拉雅型、冈底斯型和昆仑型。

In the paper, the author summarizes various views and modles about the uplifting of the Qinghai-Tibet Plateau, and then based on the features of the Cenozoic deformation and lithosphere fabric, he proposes a new dynamic model for the uplift of the Qinghai-Tibet plateau-the lithosphere deep-level expansion model. The basic view of the model that the intense subduction of the Indian plate beneath tbe Eurasian plate would result in inhomogeneity of the fabric and deformation of the lithosphere and repeated alternations of normal transformation from collision to contraction (gravity inequilibrium) to stretching (isostatic adjustment) and reverse transformation from stretching to contraction. On that basis three orbgen types can be recognized in the plateau: the Himalayan, Gangdise and Kunlun types.