分频重构技术在砂泥岩薄互层储层预测中的应用

Application of the frequency division reconstruction technology in thin interbedded sand and sale reservoir prediction

本文在地质研究的基础上,通过岩心和测井解释,分析不同频率尺度测井曲线反映的储层意义,优选研究区底砂岩段砂泥薄互层储层岩性敏感曲线。在曲线处理基础上,利用曲线分频拟合原理,小波分解提取反映薄互层岩性变化的中频中尺度伽马曲线和反映库姆格列木群层速度的低频大尺度声波曲线,利用统计模型信息融合构建声波量纲的拟声波曲线。在沉积模式的指导下,运用测井约束地震反演思路,采用全局寻优反演算法,恢复地震资料高频和低频信息,提高地震资料分辨率,预测薄互层储层分布。研究表明,曲线分频重构拟声波反演能有效提高地震资料分辨率,刻画复杂沉积背景下薄互层储层分布。

Based on the geological research and core and log interpretation, the significance of the reservoir reflected by the bore logs in different frequency scale is analyzed, and the curves which are sensitive to the lithology change of the thin interbedded sand-shale reservoirs at lower sand section of the Kumugeliemu Formation of Paleocene in the study area are optimized. On the basis of curve processing and applying the principle of log frequency division matching, the mesoscale （medium frequency） GR curves which reflect the lithological change of the thin interbedded and the large scale （low frequency） AC curves which reflect the interval velocity of the Kumugeliemu Formation are extracted by wavelet decomposition, and the quasi acoustic curves of the acoustic dimension are constructed by the statistical model information fusion. Under the guidance of depositional model and using well logging constraint seismic inversion, both the high frequency and the low frequency are recovered to improve the resolution of the seismic data by the global optimization inversion, and the distribution of the thin interbedded reservoir are predicted. The result shows that the curve frequency division reconstruction pseudo sonic logging inversion could be used to improve the seismic resolution effectively, and to describe the thin interbedded reservoir in complicated depositional setting.