玛湖凹陷三工河组油层低阻成因  

Genesis of Low⁃Resistivity Reservoirs in Sangonghe Formation,Mahu Sag

作　　者：齐媛 韩东威 杜引鱼 周伟军 QI Yuan;HAN Dongwei;DU Yinyu;ZHOU Weijun(School of Earth Sciences,Yangtze University,Wuhan,Hubei 430100,China;No.2 Oil Production Plant,Xinjiang Oilfield Company,PetroChina,Karamay,Xinjiang 834000,China)

机构地区：[1]长江大学地球科学学院,武汉430100 [2]中国石油新疆油田分公司采油二厂,新疆克拉玛依834000

出　　处：《新疆石油地质》2023年第2期151-160,共10页Xinjiang Petroleum Geology

基　　金：国家自然科学基金(4207119)。

摘　　要：准噶尔盆地玛湖凹陷南斜坡侏罗系三工河组低阻油层广泛分布,油水界面不清晰,油层形成机理复杂,识别难度大。根据玛湖凹陷侏罗系三工河组油层地质特征,结合化验分析、试油试采、录井、测井等资料,系统剖析油层低阻的成因。结果表明:研究区三工河组二段储集层岩屑以凝灰岩为主,压实与溶蚀作用使储集层微裂缝和微孔发育,储集层孔隙结构复杂化,束缚水饱和度偏高;束缚水饱和度偏高和地层水矿化度高是三工河组油层低阻的主要因素;储集层以细砂岩和粉砂岩为主,黏土矿物以高岭石和伊蒙混层为主,为油层低阻的次要因素。该研究成果在研究区油层识别中应用效果良好,为玛湖凹陷三工河组低阻油层的评价提供了一定的理论依据。The widespread low‑resistivity oil reservoirs in the Jurassic Sangonghe formation on the southern slope of the Mahu sag in the Junggar basin are difficult to identify due to their complex formation mechanisms and unclear oil‑water contacts.According to the geological characteristics of these reservoirs,and combined with the data from laboratory analysis,formation test,production test and logging,the genesis of the low‑resistivity reservoirs were systematically analyzed.The results show that the reservoirs in the second member of Sangonghe formation(San‑2 member)in the study area contain mainly tuff debris and have microfractures and micropores resulted from compaction and dissolution,leading to complex pore structure and high irreducible water saturation.High irreducible water saturation and high formation water salinity are the main geneses of the low‑resistivity of the reservoirs in the Sangonghe formation.The reservoir rocks are finegrained,mainly composed of fine sandstone and siltstone,and contain clay minerals dominated by kaolinite and illite/smectite,which are the secondary genetic factors of low‑resistivity reservoirs.The research results have been applied satisfactorily in the identification of reservoirs in the study area,providing a certain theoretical basis for evaluating low‑resistivity reservoirs of the Sangonghe formation in the Mahu sag.

关 键 词：准噶尔盆地 玛湖凹陷 三工河组 低阻油层 地层水矿化度 束缚水饱和度 凝灰岩岩屑 

分 类 号：TE112.22[石油与天然气工程—油气勘探]