浅谈利用正态分布法识别水淹层

On Identification of Watered out Zones by Normal Distribution Method.

运用正态分布法（Ｐ１／２）识别油水层是早期测井解释中常用的方法。将其用于水淹层解释中，也见到了明显的效果。用正态分布图法解释水淹层时，图中出现几个台阶，不同台阶反映不同的水淹程度。该方法也可以用于计算水淹层的混合液电阻率。用正态分布图确定的水淹层不仅包括了利用自然电位曲线反映地层水矿化度明显变化的储层，还可以解释目前一些常规方法难以识别的水淹层。

Normal distribution method is a regular practice to identify oil and water bearing rocks in the early stage of log interpretation. Now it is used to distinguish watered out zones, the results of which are obviously good. There are many different steps in the probability chart, which reflect different watered degrees. The method can also be used to calculate the resistivity of the mixed liquid in the pores of watered out zones. The watered out zones from the normal distribution chart include not only the zones with variable formation water salinity provided by the SP curves, but also the watered out zones identified by the current conventional interpretation method.