摘要
针对滨里海盆地东缘的扎纳若尔油田东南三维区块的地下地质特点,采用了基于处理叠加速度谱的射线追踪法进行速度场建立和变速成图。该法利用计算机模拟野外观测系统,将地下介质抽象为倾斜层状均匀介质,按实际的覆盖次数和炮检距,根据最小走时费马原理,用带炮检距的射线追踪方法,求出初始层速度模型;再根据最小二乘原理,将计算出的叠加速度与对应谱点的实际叠加速度比较,得到与叠加速度匹配最好的层速度;依此逐点逐线计算,最终获得整个工区的层速度模型。经过2006年的实际应用,在该区块重新落实了2号构造,并在该构造高部位设计了A3和A4两口井,其中A3井已完钻,目的层KT-Ⅰ和KT-Ⅱ顶界分层与设计分层误差分别为6m和7m,并在这两段地层中见到油气显示。
According to the subsurface geologic characters of 3-D block in southeastern part of Zanano'er Oilfield, eastern margin of Precaspian Sea, we a-dopted processed stack velocity spectrum-based ray-tracing approach to carry out the buildup of velocity field and velocity-variable mapping in the region. The method uses computer to simulate the field geometry, taking underground medium as dip layered uniform medium synthetically,according to practical folds and offsets and based on minimum travel-time principle (Fermat's principle), and u-sing ray-tracing approach with offsets to compute initial interval velocity model; then,based on minimum square principle, comparison of computed stack velocity with practical stack velocity at corresponding spectrum points yielded the interval velocity best matching with stack velocity; the computation is carried out point by point and line by line in abovementioned order, and finally we got the interval velocity model in whole work area. Through practical application in 2006, No. 2 structure was redetermined in the block, well A-3 and well A-4 were designed at height of the structure, and well A-3 was drilled well, the layering errors between the practical drilled and the designed top interfaces of targets KT-Ⅰand KT-Ⅱare 6m and 7m respectively, and hydrocarbon show were seen in these two layers.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2007年第B08期26-29,共4页
Oil Geophysical Prospecting
关键词
盐丘
变速成图
射线追踪法
DIX公式
时深转换
salt dome, velocity-variable mapping, ray-tracing approach,Dix formula, time-depth conversion
