基于体波走时和面波频散联合反演获取青藏高原东北缘壳幔精细速度结构研究

The strong uplifting of Tibetan Plateau is generally believed to be closely related to the India-Asia collision. However, it is still not clear that the role of Asian lithosphere on the uplifting of Tibetan Plateau. The mechanisms of the crustal thickening, the origin and implication of the low-velocity layer in the crust also requires further studies. The detailed crustal and upper mantle structure can constitute an important source of information for studying the tectonic evolution of the Tibetan Pateau. The seismic body wave and surface wave imaging methods can reveal the velocity structure in high resolution, but be lack of the Vp/Vs structure that reflects the physical information. On the basis of the data of 1000 broadband mobile seismic stations and the data of regional permanent stations deployed in the northeastern margin of Tibetan Plateau, we aim to obtain the velocity structure (Vp, Vs and Vp/Vs) by jointly inverting the body wave traveltime and surface wave dispersion. The results are expected to offer reliable deep structure information for understanding the tectonic evolution of the Tibetan Plateau.

印度-欧亚大陆的碰撞引起了青藏高原的隆升和地壳加厚，然而关于亚洲岩石圈在青藏高原隆升过程中所起的作用和青藏高原地壳增厚机制及壳内低速层的成因、构造意义仍有待进一步研究。可靠的地壳上地幔精细结构可以为研究青藏高原构造演化过程提供重要的约束信息。传统地震体波和面波成像单方法可以获取高分辨地壳上地幔速度结构，但缺少可以反映物性结构的Vp/Vs信息，在综合地球物理解释中容易陷入困境。本项目拟利用在青藏高原东北缘布设的1000余套宽频带流动台站和固定台站采集的地震数据，采用体波走时和面波频散联合反演方法获取青藏高原东北缘地壳上地幔Vp、Vs及Vp/Vs结构，为探讨青藏高原构造演化提供可靠的深部结构信息。

印度-欧压大陆的碰撞引起了青藏高原的隆升和地壳加厚，然而关于亚洲岩石圈在青藏高原隆升过程中所起的作用和青藏高原地壳增厚机制及壳内低速层的成因、构造意义仍有待进一步研究。传统地震体波和面波成像单方法可以获取高分辨地壳上地幔速度结构，但缺少可以反映物性结构的Vp/Vs信息，在综合地球物理解释中容易陷入困境。本项目利用在青藏高原东北缘布设的1000余套宽频带流动台站和固定台站采集的地震数据，采用体波走时和面波频散联合反演方法获取了青藏高原东北缘地壳上地幔Vp、Vs及Vp/Vs结构，为探讨青藏高原构造演化提供可靠的深部结构信息。