Abstract：The datum is an important parameter in statics calculation.The general assumption in calculating static correction is that the near-surface raypaths travel vertically,which does not conform with the actual travelling path of ray.If selecting different datum,the corresponding results of velocity analysis and stack are different too.So the errors of static corrections resulted from the assumption brings a bad results.The paper analyzed the relation between the errors of static corrections and the position of datum as well as the structure of low velocity layer,analyzed the results of velocity analysis for different floating datum and influence of the errors of calculating static corrections and presented the determination method for floating datum having minimum errors of calculating static corrections.The stack velocity calculated on the floating datum depends on the velocity of medium underlying the low velocity layer and is independent of topography and low velocity layer.The stack velocity resulted from using the method for static correction can be directly used for time-depth transformation; the root-mean-square deviation of time after NMO is smaller, which is suitable to realize in-phase stack.
林伯香 . 最小静校正误差浮动基准面方法[J]. 石油地球物理勘探, 2003, 38(6): 611-617.
Lin Boxiang. A new method for determination of floating datum in static corrections. OGP, 2003, 38(6): 611-617.
