基于差分进化算法的煤系地层泥质曲线重构

山西聚煤区煤成游离气目的层段自然伽马曲线有高值异常,测井解释岩性不准确。为了解决该问题,首先分析比对研究区内3口有自然伽马能谱测井资料的钻井,然后结合测井曲线纵向分辨率匹配技术,确定去铀伽马曲线与自然伽马曲线相关关系目标函数;并利用差分进化算法寻优在频率域确定滤波器,构建了新的去铀伽马曲线。利用该方法获得的曲线较平滑,避免了平滑滤波中丢失薄层信息,与实测去铀伽马曲线相关系数较高。将计算模型推广应用于研究区其他气井,计算结果与岩心分析资料一致,较好地解决了游离气高伽马储层段泥质含量计算问题。

On the Method of Clay Content Calculation in Coal Strata Regions Based on DE Alogrim

Although a coal strata gas reservoir in Shanxi region has a high value of natural gamma, it is not caused by shale content cannot reflect the true value of the clay. In this paper, the writers examined 3 wells that have the Natural Gamma Ray Spectrometry logging data. On the basis of the longitudinal resolution matching technology, we get the correlation objective function of CGR and GR curve. And then we use the DE (differential evolution algorithm) in the frequency domain to determine the filter to build a new without uranium gamma curve. The results are in good agreement with the original CGR curve. Then we applied the model to the other wells without the Gamma Ray Spectrometry log data, obtained good results.