频散属性在致密薄储层识别中的应用

Application of frequency-dispersion attributes in identification of tight thin interbedded reservoirs

针对鄂北大牛地气田致密砂岩薄互层储层识别预测难题,首先通过正演模拟分析不同储集条件下反射系数与频率的相关性及其频散程度;进而利用反演谱分解方法的地震道分解与重构技术获得实际地震资料的分频剖面,研究储层响应的纵波分频能量变化特征;在此基础上完成了研究区三维地震资料的频散属性提取,从剖面和平面上进行目标储层段的含气性分析预测。应用研究结果表明,频散属性预测结果与已知井吻合较好,证明了频散属性用于研究区致密砂岩薄互层储层预测的有效性。

Aiming at the problems for reservoir prediction on the tight thin interbedded layer in Daniudi Gasfield,firstly,we carry out forward modeling to analyze the correlation of reflectivity coefficient and frequency for differ ent reservoir accumulated conditions and its frequency dispersion degree.Then,frequency division profiles of actual seismic data are obtained by seismic trace decomposition and reconstruction techniques from the inversion spectral decomposition method to study the frequency division energy variation rules of P wave in reservoirs.On the basis of this,the frequency-dispersion attributes of 3D seismic data is extracted.Moreover,hydrocarbon content analysis is carried out from plane and section direction.Application results indicate that frequency dispersion prediction results are coinciding well with the well data,which proves the effectiveness of frequencr-dispersion attributes in identification of tight thin interbedded reservoirs.