致密砂岩在地震频带内波的频散与衰减物理机制研究

Both the wave dispersion and attenuation are primary parameters to characterize the reservoir attributes. For the tight sandstone, comparing with the conventional sandstones, it appears complicated pore-crack structure, highly inhomgeneous, and small conctrast of physical properties between the reservoir and surrounding rocks. Therefore, the physical mechnism standing behind the measured data of wave disperion and attenuation in the seismic frequency bands is still needed to be studied. We propose to consider the direct measurement data of wave dispersion and attenuation as basis, then the relationship between the measured data and physical properties of tight sandstone is built. After that, the reasonable operator is used to deduce the euqation including physical paramters of tight sandstone. Finally, the relationship between the seismic response and physical paramters and geometry of tight sandstone can be built to characterize the sweet spot.

波的频散与衰减是刻画储层特征的两个重要参数。对于致密砂岩，由于其具有孔隙裂隙结构复杂、非均质性强、储层与围岩物性差异性小等特点，地使得震频段内波频散与衰减物理机制依然需要进一步研究。针对此问题，申请人拟利用地震频带的直接测量的波频散与衰减数据作为切入点，建立测量数据与测量条件及岩石物性之间的关系；进而从孔隙介质波动理论出发，引入合理表征算子，推导含有致密砂岩物性特征参数的波频散与衰减表达式，建立地震响应特征与致密砂岩物性特征和几何结构的映射关系。项目的研究成果将为致密砂岩储层油气藏有利区（甜点）识别提供基础理论支撑。

对于致密砂岩，由于其具有孔隙裂隙结构复杂、非均质性强、储层与围岩物性差异性小等特点，本项目主要研究了地震频段内波频散与衰减物理机制。针对此问题，申请人利用地震频带的直接测量的波频散与衰减数据作为切入点，建立测量数据与测量条件及岩石物性之间的关系；进而从孔隙介质波动理论出发，引入合理表征算子，推导含有致密砂岩物性特征参数的波频散与衰减表达式，建立地震响应特征与致密砂岩物性特征和几何结构的映射关系。项目的研究成果将为致密砂岩储层油气藏有利区（甜点）识别提供基础理论支撑。