基于流体弹性阻抗反演的储层含油气性识别方法

Identification method for oil-gas reservoirs based on fluid elastic impedance inversion

流体弹性阻抗反演是一种能将反映储层流体效应的敏感参数从弹性波阻抗数据体中直接求取出来的地震反演方法.该方法不仅具有抗噪性、直观性强的特点,而且有效地避免了间接提取流体因子存在的累积误差问题.在双相介质理论和岩石物理实验指导下对岩石固液效应解耦,构建出凸显孔隙流体效应的流体等效体积模量参数,并推导了其流体弹性波阻抗方程,最后综合利用地质、测井和地震资料,完成对埕岛地区下第三系不整合圈闭储层的含流体检测,进一步明确了该地区含油气储层物性横向变化的认识,具有良好的实际应用效果.

Fluid elastic impedance inversion is a pre-stack inversion technique which can directly extract fluid sensitive factor from the elastic wave impedance inversion data volume. This method not only has anti-noise,highly intuitive features,but also effectively avoid the problem of indirect extraction fluid accumulated error factor exists. In this paper, we have the fluid-matrix decoupled and build the effective fluid bulk modulus to highlight the pore fluid effect based on the two-phase media theory and petrophysical experiment. Then we derive the fluid elastic wave impedance and use geology,logging and seismic data to complete fluid detection of Chengdao Tertiary unconformity traps reservoir,further clarifying the distribution of the region＇s oil-gas reservoirs in the lateral variation of physical properties,with a good practical application.