Block modeling and segmentally iterative ray tracing in complex 3D media Xu, Tao ; Xu, Guoming ; Gao, Ergen ; Li, Yingchun ; Jiang, Xianyi ; Luo, Kaiyun Abstract Publication: Geophysics Pub Date: 2006 DOI: 10.1190/1.2192948 Bibcode: 2006Geop...71T..41X