四川盆地海相页岩天然气散失定量表征

Quantitative Characterization of Marine Shale Gas Loss in Sichuan Basin

通过实验测定天然气在岩石中的扩散系数,分析天然气在岩石中扩散系数的影响因素,重点讨论页岩的TOC、矿物类型以及温压条件对页岩气扩散系数的影响机理,为建立页岩气扩散系数经验公式模型提供依据。基于基质孔隙和裂缝系统不同流体散失机理,建立页岩不同演化阶段气体散失量表征模型,定量评价四川盆地海相页岩不同演化阶段的天然气散失量,有利于确定现今页岩气的丰度和工业价值。

By experimentally determining the diffusion coefficient of natural gas and analyzing the influencing factors of natural gas diffusion coefficient in rocks,this study focuses on the mechanism of TOC,mineral types,and temperature-pressure conditions on the diffusion coefficient of shale gas.It provides a basis for establishing an empirical formula of shale gas diffusion coefficient.Based on different fluid loss mechanisms in matrix pores and fracture systems,a characterization model of gas loss in different evolution stages of shale is established to quantitatively evaluate the natural gas loss in different evolution stages of marine shale in the Sichuan Basin,which is conducive to determining the abundance and commercial value of shale gas today.