针对目前AVO反演技术中普遍使用的Aki-Richards,Shuey和Hilterman近似式,以Zoeppritz方程的精确解为参照,针对4种常见的含气砂岩类型,分别利用3种近似式计算AVO响应,并绘出相对误差随入射角的变化曲线.通过对比与分析发现:Aki-Richards和Shuey近似式计算结果均较Zoeppritz方程精确解误差更小,Hilterman近似式计算结果误差较大;特别是在大角度入射时,Shuey近似式计算结果更为精确、稳定;不同储层条件下,3种近似式的误差百分比不同,曲线特征不一致,整体上3种近似式在第Ⅲ类AVO气藏条件下误差均较小,计算结果的精确度均较高.3种近似式对4种典型含气砂岩类型给出的定量分析结果为优选储层参数反演方法提供了理论依据.%Based on three common approximate formulas including Aki-Richards,Shuey and Hilterman in AVO inversion technology and four types of gas-bearing sandstone,three approximate formulas were calculated for AVO response in comparing with Zoeppritz exact value. Both relative error and incident angle curves were plotted. The results show that Aki-Richards and Shuey approximate formulas own lower approximate errors than that of Hilterman approximate formula for the interface of four class gas-bearing sandstone. The accuracy of Shuey formula rises with the increase of the incident angle. Under different reservoir condi-tions,three approximate formulas'calculation results possess different percentage errors and curve charac-teristics,and all approximate formulas are more applicable for the third type AVO response. Quantitative analysis result which is calculated by three approximate formulas in four types gas-bearing sandstones provides bene-ficial theoretical foundation for reservoir parameter inversion.
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