【摘要】 以AVO技术的基本理论为基础,应用完全形式的Zoeppritz方程合成AVO角度道集理论模型,根据Shuey近似式拟合截距P与梯度G,分析储层厚度、泊松比、速度变化对P-G交会图的影响.通过对比分析发现,三层介质P-G交会曲线为近似椭圆,储层厚度对P、G值均有影响,对交会曲线的斜率无影响,在厚度达到λ/4时,P、G绝对值最大,交会曲线延伸最长;泊松比主要影响G值,P值变化不大;储层速度的变化主要影响P值,G值变化不大.更多还原

【Abstract】 Based on the basic theories of AVO technique,AVO angle gather theoretical models are computed by using Zoeppritz equations,intercept P and gradient G values are fitted according to Shuey’s approximation,then analyse influences of thicknesses,Poisson’s ratios and velocities on P-G crossplots.By comparing and analyzing,we find that P-G crossplot curves are nearly ellipses for three formations media.Reservoir thickness influences P and G,but don’t influences the slope of the trend line.When the thickness reaches to λ/4,absolute values of P and G are all the biggest,the trend line is the longest.Poisson’s ratios have a big influence on G,and P keeps fixity nearly;velocities have a big influence on P,and G keeps fixity nearly.更多还原