基于AVO的属性分析

针对川中地区砂体分布多,气藏分布在砂体的那个位置很难确定这一情况,对叠前数据用AVO中的Lambda-Mu-Rho技术获得流体的不可压缩性和硬度。同时对道集模型进行AVO分析处理,总结出不同流体饱和度情况下的地震响应特征;将分析结果与实际井旁道地震资料对比,从而建立可靠的储集层性质与地震响应特征的对应关系,为从地震资料中提取储集层参数提供了依据。利用Biot-gassman流体替换模型,分别求得模型在含油砂岩、含气砂岩和含水砂岩时的对应响应,即获得了多个点的截距-梯度交汇图。然后利用用AVO流体反演定量的得到流体的可能性分布,根据这些叠前属性再结合叠后反演的多个属性,综合评定了该区的气藏分布情况,通过已钻遇的井证实了预测的可靠性,该方法充分的应用了地震的叠前信息,解决了叠后反演所不能解决的流体分布预测问题,在砂体范围内找含流体可能性最大的砂,从而降低了勘探风险。

AVO ATTRIBUTE ANALYSIS

When sandstone distribution is wide, the gas reservoir distribution is difficultly to be located in Chuanzhong. The paper discusses that we may obtain incompressibility and rigidity of rock parameters from pre-stack data by the Lambda-Mu-Rho. And at the same time, with the seismic data analyses by AVO, the relationship between seismic response characters and sandstone with different type of porosity fluid is established, And the fluid probable distribution is determined with AVO fluid invention. Based on these attributes and the multi-attribute of post-stack data inversion, we evaluate gas reservoir distribution in the area. By using the attributes of pre-stack seismic data to forecast fluid distribution, the methods can find the sandstone with the high porosity and thus reduce exploration risk.