约束走时层析成像

地震层析成像技术是反演地下速度结构的一种重要方法。与医学ＣＴ不同，一般地震波射线对目的区覆盖不均匀，所获得的数据不充分。在这种情况下，若初始猜测不准，常规的成像方法，如阻尼最小二乘法，ＡＲＴ法等难以获得理想效果。

Restrained travel time tomography

Seismic tomography is an important technique for estimating subsurface veloci-ty structure. Unlike medical CT, seismic tomography often uses less enough databecause seismic rays fail to uniformly cover the objective area. If a poor initial mod-el is chosen in such case, conventional tomography methods, such as damped leastsquare method, algebraic reconstructioh technique etc. can hardly produce satisfac-tory results. To cope with the problem, we put forward a restrained tomographymethod, which s0lves least square problem after an inequality restriction is given.The solution of optimized problem under the restriction is deduced in the article.The idea of solving this prob1em is also app1icable to solving other non1inear re-strained optimization problems. The final numerical result and the relevant evalua-tion prove this method effective and superior in the case 0f less enough data. Whatis more, the method has certain noise resistance.