基于密集台阵与测线的人工地震和天然地震联合反演青藏高原东北缘地壳上地幔速度结构研究

利用2013年以来在青藏高原东北缘完成的50余次吨级人工爆破在区域固定台网、密集宽频带流动台阵和人工地震测深剖面上的走时记录，以及固定台网和宽频带流动台阵记录到的近震走时数据，采用复杂结构中的三维波前追踪算法和非线性多数据类型联合反演方法，进行多类型震相走时联合成像，构建研究区内5条高分辨二维P波、S波速度结构剖面，并获取青藏高原东北缘（E101°~E109°，N34°- N40°）的三维壳幔P波和S波精细速度结构，揭示研究区构造演化背景和地震发生的机制和成因，深入理解研究区强震孕育环境、地壳构造演化、高原生长及其动力学机制等相关科学问题。

In this study, we simultaneously invert refraction, wide-angle reflection and local earthquake traveltimes from reginal seismic network, broadband seismic array andcontrolled source seismic profiles to image 3-D variations in crust and uppermost mantle P-wavespeed, S-wavespeed and Moho structure beneath the northeastern margin of the northeast Tibetan plateau （E101°~E109°，N34°- N40°）. The dataset included more than 50 exploration and thousands local earthquake records in temporary broadband stations, Seismological Network of Qinghai, Gansu, Sichuan, Ningxia, Shanxi and Xinjiang, and portable digit seismograph.The temporary broadband stations were installed from 2013 to 2016 supported by non-profit public program of China Earthquake Administration. Crustal strucutre modeling and invesion technique will be applied to estiblish 5 two dimensional P- and S- wave velocity strucutre.The hybrid tomography and modeling mothod will provide the 3D crustal and uppermost mantle velocity structure of the northeastern margin of the northeast Tibetan plateau. The final model will provide seismic evidence which reveal the collision process of Indian and Asian plates, and discuss the growth mechanism of the Tibetean plateau.