低幅度构造变速成图技术

Velocity-varying mapping technique for low-amplitude structure.

本文针对塔里木盆地低幅度构造区构造成图的难点,提出了相应的速度建场和变速成图方法:通过沿层速度分析技术提高叠加速度的横向分辨率;利用叠加速度或原始叠前道集作为输入反演层速度,前者不受水平层状介质及射线垂直入射等前提条件的限制,对复杂地层产状具有更好的适应性,后者克服了叠加速度精度的影响,其精度更高;利用叠加速度闭合差校正和均方根速度闭合差校正,得到了相对精确的速度场,可用于三维时深转换;通过研究深度误差与时间、速度、埋深等参数的相关性,找到深度误差分布规律,进而对构造图进行两次校正。与传统的直射线成图技术相比,此法可明显提高低幅度构造区深度域构造图的精度。

In view of difficulty of structural mapping in low-amplitude structural area of Tarim basin,the paper presented relevant velocity field-building and velocity-varying mapping method;Using horizon-oriented velocity analytic technique to improve the lateral resolution of stack velocity;using stack velocity or raw prestack gathers for input inverted interval velocity the former does not have restriction of such preconditions as horizontal layered medium and ray vertical incidence,having better adaptability to c...