INPEFA技术在层序地层划分中的应用——以苏北盆地溱潼凹陷南华区块阜三段为例

Application of INPEFA technology to sequence stratigraphy of the third member of Funing Formation, Nanhua block, Qintong Sag, North Jiangsu Basin

最大熵谱分析技术是对测井曲线进行合成预测误差滤波分析处理,得到频率趋势线(INPEFA曲线),运用INPEFA曲线不同幅度的趋势拐点来识别不同级次层序界面。通过对苏北盆地溱潼凹陷南华区块阜三段GR曲线进行INPEFA处理,将阜三段III和IV油组划分为13个5级层序,进而在INPEFA曲线所建立的等时框架内对区块内距离相近的3口井进行井间的砂体连通性对比,得出在小层中各有2个连通性较好的砂层和油层组。INPEFA技术处理后的测井曲线可以提取出在常规测井曲线中隐藏的旋回趋势特征,从3口井变化趋势相近的INPEFA曲线来看,该区域的沉积环境变化大致相同,都是从水退到水进的过程。

The maximum entropy spectrum analysis technique provides the frequency trend line （INPEFA curve） by analyzing the synthetic prediction error filtering of logging curves, and using the trend turning point of different amplitude of the INPEFA curve to identify the interface of different order sequences. Through the INPEFA treatment of the GR curves of the third member of Funing Formation in the Nanhua block in the Qintong Sag of the North Jiangsu Basin, the III and IV oil groups were divided into 13 five-level sequences, and then the sand body connectivity among three wells with close distances within the block was compared in an isochronous frame-work established by INPEFA curves. Comparing the sand body connectivity, it was concluded that there were two sand layer groups and oil layer groups connected in the small layer. The logging curves processed by INPEFA technology can extract the characteristics of cyclic trends hidden in conventional logging curves. According to the INPEFA curves with similar trends in the three wells, the sedimentary environment in this area changed roughly the same, from regression to transgression.