准噶尔盆地中拐凸起石炭系火山岩油气成藏特征

摘要

The carboniferous volcanic reservoirs in Zhongguai Uplift are dominated by lavas and pyroclastic rocks. The reservoirs mainly contain pores,microfractures and dissolution pores.The reservoir shows low porosity and low permeability as a whole,which can be divided into four categories according to porosity and permeability and pore structure.Lithologic,lithofacies,fault structures and weathering leaching can control the porosity and permeability of reservoirs by affecting the formation and subsequent alteration of pore seams,thereby controlling the reservoir's reservoir capacity. The results of oil source comparison show that the source rocks of Wuerhe Formation, Fengcheng Formation and Jiamuhe Formation of Permian contribute oil to the Zhongguai Uplift. Carboniferous volcanic reservoirs in Zhongguai have excellent caprock and preservation conditions.Crude oil migrated to the traps through faults and unconformities to accumulate.%中拐凸起石炭系火山岩储层以发育熔岩和火山碎屑岩为主,储集空间主要有气孔、微裂缝和溶蚀孔.该储层整体表现为低孔隙度和低渗透率,根据孔隙度和渗透率以及孔隙结构等可将其分为四类.岩性岩相、断裂构造和风化淋滤作用通过影响孔缝的形成与后期改造来控制储层的孔隙度和渗透率,进而控制储层的储集能力.油源对比结果表明,二叠系乌尔禾组、风城组和佳木河组烃源岩均对中拐凸起的原油起到贡献作用.中拐凸起石炭系火山岩储层具有优质的盖层和保存条件,原油经断裂和不整合面运移至圈闭中聚集成藏.