摘要
青藏高原各地体的地壳结构与厚度存在明显差异,依据过去多年中法合作的地震探测资料结合其它资料给出了青藏高原的地壳结构图。对高原多数地体的地壳中存在的低速层进行了研究,表明低速层的形成主要来自地体碰撞时,地壳的推覆叠置,使部分高原浅部上地壳的中酸性成分地层进入中下地壳的位置,仍为长英质岩性成分,尚未跨越固相点进入部分熔融状态。
There exist evident differences in crustal structure and thickness among various terranes in Qinghai-Tibet Plateau. The crustal structure histograms of these terranes are presented. Studies show that it is the tectonic superposition of the crust caused by the collision of terranes that results in the development of the low-velocity layers in the crust of most terranes. The shallower crustal layer with felsic-intermediate composition is considered to be the lower half of the crust, with the original composition preserved. The materials of the low-velocity layers have not been subjected to partial melting because the temperature remains lower than the melting solidus.
出处
《物探与化探》
CAS
CSCD
2004年第4期290-293,共4页
Geophysical and Geochemical Exploration
基金
中法合作青藏高原地质地球物理研究成果(2001010201)
关键词
青藏高原
低速层
部分熔融
Qinghai-Hibet Plateau
low-velocity layer
partial melting
