南华北盆地太康隆起煤系页岩气地质特征及勘探潜力

基于南华北盆地上古生界煤系页岩气勘探实践及认识,通过研究该区页岩气烃源岩地球化学特征、储集层特征、含气性特征,总结页岩气地质特征,分析勘探潜力。页岩气主要发育于太原组、山西组,烃源岩有机质类型以Ⅲ型为主,镜质体反射率为2.1%~3.4%,处于过成熟阶段;太原组、山西组泥页岩有机碳含量均值分别为2.34%、1.66%;页岩气储集层矿物成分以石英、黏土矿物为主,主要储集空间类型为矿物质孔和微裂缝;太原组、山西组页岩含气量均值分别为1.73 m³/t、1.55 m³/t,相对于海相页岩含气特征属于中等—偏高的范围;采用容积法计算页岩气地质资源量为7112×10⁸m³,资源丰度为2.54×10⁸m³。经综合对比评价认为庄头斜坡、杞县凹陷是南华北盆地太康隆起页岩气较为有利的勘探目标区。

Coal Measures Shale Gas Geological Features and Exploration Potential in Taikang Uplift,Southern North China Basin

Based on upper Paleozoic coal measures shale gas exploration practices and knowledge,through shale gas source rock geochemical,reservoir and gas-bearing features in the area have summarized shale gas geological features and analyzed exploration potential.Shale gas in the area is mainly developed in the Taiyuan and Shanxi formations,source rock organic matter mainly belongs to typeⅢ;vitrinite reflectance 2.1%~3.4%thus in stage of over-maturity;argillutite organic carbon content averages in Taiyuan and Shanxi formations are 2.34%and 1.66%respectively.Mineral components in shale gas reservoir have mainly quartz and clay minerals;reservoir spaces mainly mineral matter pores and microfissures.Gas content averages of Taiyuan and Shanxi formations are 1.73 m³/t and1.55 m³/t respectively;in contrast with marine shale gas content features the ranges should belong to medium to on the high side.Shale gas geological resources through volumetric method estimation have 7112×10⁸ m³,resource abundance 2.54×10⁸ m³.The comprehensive analytic assessment has shown that the Zhuangtou slope and Qixian depression are two shale gas relatively favorable exploration targets in the Taikang uplift,southern North China Basin.