滩坝砂储层地震解释存在的问题及对策

Problems and countermeasures in seismic interpretation of beach bar sandstone reservoirs

滩坝砂油藏是一类特殊的低渗透薄互层油藏,储层埋深大、横向变化快、地震资料纵向分辨率低,用常规方法很难实现精细解释。本文对滩坝砂储层地震解释中存在的主要问题进行了分析,在此基础上,集中研究了基于希尔伯特—黄变换(HHT)的滩坝砂储层拓频、基于三参数小波的滩坝砂薄互层检测、能量半时特色属性分析、古地貌与地震属性融合显示这4项对策。研究结果表明:①基于HHT的拓频方法,能较好地展宽目标层频带,增强滩坝砂弱信号的能量;②以三参数小波为分析小波,可以较好地刻画滩坝砂薄互层的内部结构;③能量半时属性是整体描述滩坝砂储层的最佳属性;④将古地貌信息作为一种属性参与属性融合,是研究滩坝砂储层的一种特色技术,值得推广应用。

Beach bar sandstone reservoir belongs to a special class of low permeability and thin interbed reservoir.This kind of deeply buried reservoir shows low vertical resolution and fast lateral variation on seismic sections.So it is difficult to do fine interpretation with conventional methods.We analyze difficulties in seismic interpretation of beach bar sandstone reservoir,and put forward four countermeasures, i.e. HHT(Hilbert-Huang transform)extended frequency,three-parameter wavelet detection,energy half time attribute prediction,fusion display of ancient landform and seismic attributes.HHT extended frequency can extend the frequency of the targets and enhance weak signal energy of beach bar sandstone.The three-parameter wavelet can well describe the internal structure of beach bar sandstone.The energy half time attribute is the best seismic attribute to describe the entire beach bar sandstone reservoir.As a kind of attributes,the ancient landform information can be used in fusion display.