四川盆地高磨地区龙王庙组储层岩石流体概率识别技术

四川盆地高石梯—磨溪地区下寒武统龙王庙组气藏储层的岩性与流体性质地震识别难度较大,主要原因是不同岩性、不同流体性质地层的岩石物理参数往往存在着较大的重叠空间,由此增加了识别的不确定性与多解性。为破解上述难题,采用岩石流体概率识别技术进行了尝试。该方法首先依据岩石物理参数分析结果建立各种岩性、流体性质的概率分布函数,再根据联合求解来确定储层的岩性及流体性质的概率,以此开展岩性、流体性质识别。应用结果表明:较之于一般的叠前反演方法,该方法通过多弹性参数对的联合概率求解,既提高了对储层岩性、流体性质识别的精度,又为提高储层岩性、流体性质识别的可靠程度提供了量化依据,可以为油气藏勘探开发井位部署决策等提供更充足的量化参考指标和依据。

The lithologic fluid probability identification technologies for Longwangmiao Formations in Gaoshiti-Moxi area,Sichuan Basin

Great difficulties have been encountered in seismic identification of lithologic and fluid properties in Lower Cambrian Longwangmiao Formations in the Gaoshiti - Moxi Area, Sichuan Basin. Petrophysical parameters of formations with different lithologic and fluid properties may overlap with each other, and consequently may lead to uncertainties and multiplicity of solutions to identification results. To solve the problem, lithologic fluid probability identification techniques were deployed. First of all, functions for the probability distribution of various lithologic and fluid parameters were established in accordance with the analysis of petrophysical parameters. Then, joint solution was reached to determine the probabilities related to lithologic and fluid properties of reservoir formations to identify lithologic and fluid properties. Research results show that compared with conventional pre-stack inversion methods, the new method may solve the problem through joint probability determination of multiple elastic parameters to enhance the prediction accuracy of lithologic and fluid properties to provide quantified basis for promoting the reliability in determing lithologic and fluid properties. In conclusion, relevant research results may provide sufficient quantified indexes and foundations for the deployment of wells in the exploration and development of gas reservoirs.