摘要
西藏地壳是指西藏高原内中-新生代造山带的地壳。其面积210万km^2,地壳平均厚度63.5km,地壳体积1.32亿km^3,地壳内的岩石平均密度2.775g/cm^3,地壳质量3663地克(=3.663×10^(17)吨)。西藏地壳由五个槽壳构成。它们是松潘甘孜槽壳、三江槽壳,喀拉昆仑唐古拉槽壳,冈底斯念青唐古拉槽壳和喜马拉雅槽壳。根据现有的地质学、地球物理学、地球化学和地理学资料,本文概略地给出了西藏地壳模型及其化学成分。
The Xizang crust is one belonging to the crogenic belts formed during Mesozoic-Cenozoic era in Xizang region. Its fundamental data are: Area 2.1×10~6km^2, average thickness 63.5km, volume 1.32×10~8km^3, average density of rocks 2.775g/cm^3, mass 3663 Gg (=3.663×10^(17) metric tons).
The Xizang crust is composed of five fold orusts, i.e. the Songpan-Ganze fold crust, the Sanjiang fold crust, the Karakorum-Tanggula fold crust,the Gandise-Nyainqentanggula fold crust and Himalayan fold crust. Based on the data from the geological, geophysical, geochemical and geographical surves in this region, the model of the Xizang crust and its chemical composition are roughly presented in this paper.
关键词
西藏
地壳
化学成分
元素
丰度
Xizang(Tibet) crust, chemical composition, crustal model, abundance of chemical elements
