【摘要】 根据Shuey近似式对AVO理论模型拟合AVO截距与梯度,通过分析砂泥岩单界面模型、泥岩夹含气砂岩模型、泥岩与含气砂岩薄互层模型,得出3类含气砂岩截距-梯度交会图的分布特征,根据截距-梯度交会点在截距-梯度交会图上的分布特征可以识别出含气砂岩并将其分类.分析了砂岩储层厚度变化对截距-梯度交会图的影响,其厚度的变化引起截距-梯度交会曲线的分布宽度和延伸长度的变化;通过分析目的层同相轴的截距-梯度交会图,可以指导含气储层及其厚度预测.更多还原

【Abstract】 AVO intercept and gradient values are fitted according to Shuey’s simplified equation.By analyzing intercept gradient crossplots of sand shale single interface models,shale interbedded with gas sand models,thin shale gas sand interbeded formation models,the distributing characters of intercept gradient crossplots of three types of gas sand are obtained.Gas sands can be identified and classified according to distributing characters of intercept gradient points in intercept gradient crossplots.The influences of sand thickness variation on intercept gradient crossplots are analyzed.The variations of thickness cause variations of width and length of intercept gradient crossplot curves.Analyzing intercept gradient crossplots of interest bed events can guide gas reservoir and thickness prediction.更多还原