东濮凹陷杜寨地区沙三中-下段致密砂岩气藏有效储层物性下限  

Lower Limits of Porosity and Permeability of Tight Sandstone Gas Reservoirs in the Middle-Lower Es_3 in Duzhai Area,Dongpu Depression

作　　者：吕雪莹 蒋有录[1] 刘景东[1] 张园园[1] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580

出　　处：《地质科技情报》2017年第3期182-188,共7页Geological Science and Technology Information

基　　金：国家重大科技专项(2011ZX05006-004)

摘　　要：东濮凹陷杜寨地区沙三中-下段致密砂岩储层具有典型的低孔、低渗特征,但其储层物性下限尚不明确。为此,基于岩心实测孔隙度、渗透率和压汞资料等,综合采用经验统计法、孔隙度-渗透率交会法、最小流动孔喉半径法(水膜厚度法、Purcell法、Wall法)及压汞曲线法等多种方法,确定了杜寨地区沙三中-下段致密砂岩气藏有效储层的物性下限。结果表明,不同方法确定的物性下限值存在一定差异,杜寨地区沙三中-下段致密砂岩气藏有效储层的孔隙度下限值介于3.92%~5.306%之间,平均值为4.264%;渗透率下限值范围为0.032×10^(-3)~0.059×10^(-3)μm^2,平均值为0.038 7×10^(-3)μm^2。总体上,经验统计法确定的物性下限值较低,而最小流动孔喉半径法和压汞曲线法确定的物性下限值较高,特别是Purcell法计算所得的物性下限值明显高于其他方法,可能与其更能表征大孔喉的贡献有关。在此基础上采用算术平均法,综合确定杜寨地区沙三中-下段有效储层的孔隙度下限值为4.264%,渗透率下限值为0.038 7×10^(-3)μm^2。The tight sandstone gas reservoirs in the middle-lower Es3 are characterized by lower porosity and permeability, however their Iower limits of porosity and permeability are still unclear. Based on the measured porosity and permeability of cores and mercury injection data, this paper determined the lower limits of porosity and permeability of tight sandstone gas reservoirs in the middle-lower Es3 in the Duzhai area, comprehensively using empirical statistic method, cross plot of porosity and permeability, minimum flow pore throat radius method （including water film thickness method, Wall and Purcell methods）, and mercury injection curve method. The results show that the lower limits of porosity and permeability deter- mined by different methods are various. The lower limit of porosity ranges from 3.92% to 5. 306% and av- erages out to 4. 264%, while the lower limit of permeability ranges from 0. 032×10^-3 μm^2 to 0. 059×10^-3 μm^2 and averages out to 0. 038 7×10^-3 μm^2. Generally, the lower limits of porosity and permeability de- termined by empirical statistic method are smaller, whereas the lower limits determined by minimum flow pore throat radius method and mercury injection curve method are relatively greater, especially by the Pur- cell method, which is possibly related to its capacity for characterizing the contribution of the large pore throat. Then the arithmetic mean values are taken as the lower limits of porosity and permeability. The calculated lower limit of porosity is 4. 264% and that of permeability is 0. 038 7 × 10^-3 μm^3 for the tight sandstone gas reservoirs in the middle-lower Es3 in Duzhai area in the Dongpu Depression.

关 键 词：致密砂岩气藏 物性下限 沙三中-下段 东濮凹陷 

分 类 号：P618.130.21[天文地球—矿床学]