摘要
两组任意夹角的倾斜裂缝在自然界中具有普遍性,本文针对两组任意夹角的倾斜裂缝介质模型,采用交错网格高阶差分法进行地震波场二维三分量数值模拟。根据Hudson理论和Bond矩阵变换得到裂缝型储层在观测坐标下的弹性系数,对比了在本构坐标和观测坐标下地震波场之间的差异,分析了不同方位角下炮记录波场特征、不同炮检距方位角道集上的波场特征,以及改变裂缝夹角后在方位角道集记录上的响应特征。研究表明,裂缝型储层的各向异性特征是裂缝的综合反映,各向异性的强弱不仅与裂缝的发育强度有关,还与裂缝发育的复杂程度有关。通过对方位各向异性介质数值模拟和波场特征的分析,可为方位各向异性介质的裂缝反演提供理论基础。
The dipping fracture with two groups of arbitrary included angle can be easily founded in the nature,regarding the dipping fracture medium model with two groups of arbitrary included angle staggered-grid high-order finite-difference was used to conduct seismic wave field 2D3C numerical modeling in this paper.Based on Hudson theory and Bond matrix transformation the elastic coefficients of the fractured reservoir under the viewing coordinate system were obtained,and the difference between seismic wave field under constitutive coordinate system and seismic wave field under viewing coordinate system were correlated,the wave field characteristics of shot records with different azimuths,the wave field characteristics of azimuth gathers under different offsets,and the response characteristics on azimuth gathers when changing fracture inclined angle were analyzed.The studies above illustrates that anisotropic characteristics of the fractured reservoir is the integrated reflection of the fractures,and the anisotropic degree is not only related to the intensity of the fracture development,but also related to its complex degree.Through analyzing numerical modeling for azimuthally anisotropic media and wave field characteristics,theoretical foundation is laid for fracture inversion in azimuthally anisotropic media.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2010年第1期47-54,共8页
Oil Geophysical Prospecting
基金
国家973计划项目(2006CB202304)
