鄂尔多斯盆地富县探区上古生界气藏形成条件分析

Upper Paleozoic Gas Reservoir Formation Conditions in Faxian Exploration Area of Ordos Basin

富县探区上古生界主力烃源岩是煤系,该煤系有机质含量和成熟度均较高,是上古生界气藏的基础。工区上古生界储层大部分是低孔低渗的砂岩,无论间接盖层还是区域性盖层都为古生界气藏的保存做出巨大贡献。盆地内圈闭较为简单,主要是披盖圈闭和岩性圈闭。上古生界良好的生储盖组合和多样的成藏模式组成了一个完整的上古生界含气系统。

Upper Paleozoic primary source-rock in Fuxian exploration area is a coal system with organic matter content and maturity, higher, which is the basis of Upper Paleozoic gas reservoir . In the area , the upper Paleozoic reservoirs are mostly consisted of low porosity and low permeability sandstones, the indirect cap-rock and regional cap-rock make greater contribution for preserving the upper Paleozoic gas reservoirs. The trap is simple, it includes wrap and lithologic traps. Good assemblage of source-rock, reserve, and cap-rock and various reservoir formation modes build up an integral upper Paleozoic gas system.