深海盐成像面临难题及解决方案

Deep sea salt imaging problems and solutions

深海盐成像一直是勘探界的热点与难点。盐成像的难点主要包括速度横向变化大,常规层析反演速度不敏感,盐边界及盐底存在多射线路径等。为了解决上述问题,从速度建模与深度偏移2个方面进行研究。在速度建模方面,综合应用多参数约束初始建模技术、各向异性建模技术和盐体建模技术,得到了具有明确地质含义的速度模型。在深度偏移方面,选用射线束偏移方法,解决了盐边界多射线路径问题。研究表明,精细的速度建模加上合适的偏移算法是解决盐成像问题的关键。

Deep sea salt imaging is a hotspot and difficulty of exploration industry. Salt imaging difficulties mainly include such several aspects as large lateral velocity variation, insensitivity of conventional tomo-graphy inversion, and multiple ray paths in salt bottom and boundary. To solve the problems, the velocity modeling and depth migration are studied. The velocity modeling with geological concept is established with the technology of multi-parameters constrained modeling, anisotropic modeling and salt modeling. In depth migration, beam migration is chosen to solve salt boundary multi-ray path problem. Studies show that fine velocity modeling combined with proper migration algorithm is the key to solve the problem of salt imaging.