地震体波走时层析成像是探测地球内部速度结构的重要方法之一。基于三维块状建模以及三角形拼接的界面描述方式，结合快速高效的逐段迭代射线追踪方法，获得三维复杂地质模型中的地震射线路径与走时信息，采用共轭梯度非线性反演算法，进行地震波走时反演。实验结果表明共轭梯度反演算法在三维层状模型中具有较高的有效性。
Seismic body wave traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. The geological body is described as an aggregate of arbitrarily shaped blocks, which are separated by triangulated interfaces. A segmentally iterative ray tracing (SIRT) method is used to calculate the ray path and traveltime in 3D complex geological models. The conjugate gradient method is employed in seismic traveltime inversion of 3D geological models. Numerical tests of seismic traveltime inversion in 3D stratified models indicate the effectiveness of conjugate gradient method.
2018,39(4): 33-37 收稿日期：2017-12-03
DOI：10.3969/j.issn.1003-3246.2018.04.005
基金项目：国家自然科学基金（批准号：41604054）；中国地震局监测预报司测震台网青年骨干培养专项（项目编号：CEA-JC/QNCZ-18321）；中国地震台网中心青年科技基金课题（批准号：QNJJ201711）
作者简介：李飞(1986-),男,博士,工程师,主要研究方向为三维复杂介质中的走时反演和地震定位。E-mail:lifei@seis.ac.cn
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