准噶尔盆地盆1井西凹陷侏罗系三工河组凝析气藏特征及成因机制  

Characteristics and genetic mechanism of condensate oil and gas of the Jurassic Sangonghe Formation in western well Pen-1 sag,Junggar Basin

作　　者：乔桐 刘成林[1,2] 杨海波[3] 王义凤[4,5] 李剑 田继先[4,5] 韩杨 张景坤[1,2] QIAO Tong;LIU Chenglin;YANG Haibo;WANG Yifeng;LI Jian;TIAN Jixian;HAN Yang;ZHANG Jingkun(State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum(Beijing),Beijing 102249,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Research Institute of Exploration and Development,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China;PetroChina Research Institute of Petroleum Exploration&Development,Beijing 100083,China;Key Laboratory of Gas Reservoir Formation and Development,CNPC,Langfang 065007,Hebei,China)

机构地区：[1]中国石油大学(北京)油气资源与工程全国重点实验室,北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国石油新疆油田公司勘探开发研究院,新疆克拉玛依834000 [4]中国石油勘探开发研究院,北京100083 [5]中国石油天然气集团有限公司天然气成藏与开发重点实验室,河北廊坊065007

出　　处：《岩性油气藏》2024年第6期169-180,共12页Lithologic Reservoirs

基　　金：中国石油天然气股份有限公司重大科技专项“凝析油与轻质油形成机制、成藏条件及资源潜力研究”(编号:2021DJ0603)资助。

摘　　要：基于油气地球化学、试油结果与凝析气相态分析实验等资料,采用盆地模拟技术分析了准噶尔盆地盆1井西凹陷前哨井区侏罗系三工河组凝析气藏特征,并对凝析气藏的成藏过程与成因机制进行了详细研究。研究结果表明:①盆1井西凹陷侏罗系三工河组凝析气藏为构造-岩性油气藏,优质储层岩性主要为灰色细—中粒长石岩屑砂岩,孔隙度为2.70%~16.10%,平均为12.10%,渗透率为0.016~109.000 mD,平均为14.170 mD,属于中孔、低渗储层,与下伏的二叠系风城组和下乌尔禾组2套烃源岩形成了良好的储-盖组合。②研究区凝析油表现为低密度、低黏度、低凝固点和低含蜡量等特征,正构烷烃以低—中碳数为主,为下乌尔禾组烃源岩成熟—高成熟阶段的产物。③研究区凝析气藏天然气组分以烃类气为主,甲烷与乙烷碳同位素值分布集中,分别为-37.40‰~-36.84‰与-27.55‰~-26.54‰,为腐殖型烃源岩裂解气,来源于下乌尔禾组烃源岩。④研究区下乌尔禾组烃源岩于古近纪早期生成的凝析油气经过不断调整最终于新近纪早期充注形成凝析气藏,从成藏至现今储层流体组分未发生改变,油气藏相态类型也未发生改变,为原生型凝析气藏。Based on the analysis and test data of petroleum geochemistry,oil test and phase behavior analysis of condensate gas,basin modeling techniques were used to determine the characteristics,accumulation process and genetic mechanism of condensate gas reservoirs of Jurassic Sangonghe Formation in Qianshao well area of western well Pen-1 sag,Junggar Basin.The results show that:(1)The condensate reservoirs of Jurassic Sangonghe Formation are structural-lithologic reservoirs in western well Pen-1 sag.The high-quality reservoirs are mainly composed of gray fine-medium feldspathic detritus sandstone,with porosity ranging from 2.70%to 16.1%,an average value of 12.10%,permeability ranging from 0.016 mD to 109.000 mD,an average value of 14.17 mD.The reservoirs belong to middle porosity and low permeability reservoirs,and form reservoir-cap assemblage with two sets of source rocks from the underlying Permian Fengcheng Formation and lower Urho Formation.(2)The condensate oil in the study area is the product of the source rocks of lower Urho Formation within mature to high-mature stage,it has physical properties of low density,low viscosity,low freezing point and low wax content,and its n-alkanes are composed of low and medium carbon components.(3)The natural gas of condensate gas reservoirs in the study area is mainly composed of hydrocarbon gas,with concentrated distribution of methane and ethane carbon isotope values ranging from-37.40‰to-36.84‰and-27.55‰to-26.54‰,respectively.It was derived from the cracking of humic-type source rocks of lower Urho Formation.(4)The condensate oil and gas generated by the source rocks of lower Urho Formation in the early Paleogene were continuously adjusted and finally charged in the early Neogene to form the present condensate gas reservoirs.The fluid composition has not changed since the reservoir formation,and the fluid phase type is also unchanged,so it is a primary condensate gas reservoir.

关 键 词：凝析油 凝析气藏 腐殖型裂解气 下乌尔禾组烃源岩 油气藏相态类型 三工河组 侏罗系 盆1井西凹陷 准噶尔盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]