东海盆地西湖凹陷武云亭构造油气来源与成藏模式  

Hydrocarbon origin and reservoir forming model of Wuyunting structure in Xihu Depression,East China Sea Basin

作　　者：刁慧 邹玮 李宁 覃军 Diao Hui;Zou Wei;Li Ning;Qin Jun(CNOOC China Limited-Shanghai,Shanghai 200335,China)

机构地区：[1]中海石油(中国)有限公司上海分公司,上海200335

出　　处：《地质科技通报》2020年第3期110-119,共10页Bulletin of Geological Science and Technology

基　　金：国家科技重大专项(2016ZX05027-001)。

摘　　要：近年来,东海盆地西湖凹陷平湖斜坡带武云亭构造油气勘探获得了较好的商业发现,但已钻探的A井与B井流体性质差异较大,A井为气井、B井为油井。通过生物标志化合物对比、碳同位素分析及流体包裹体分析,对武云亭构造油气来源、充注期次及成藏模式进行了分析,结果表明武云亭构造油为正常成熟原油,主要来源于本地宁波19洼平湖组煤系烃源岩;天然气有两种,一种为高成熟天然气,主要来源于东侧主洼宁波27洼平湖组烃源岩,另一种为正常成熟天然气,主要来源于本地次洼宁波19洼烃源岩。包裹体荧光呈现为淡黄色油气包裹体和无色气包裹体,均一温度表明武云亭构造主要经历两期油气充注,时间为2 Ma和现今。武云亭构造油气来源丰富,成藏过程复杂,基于油气来源及成藏特征划分为“双源侧向晚期次生型”和“单源垂向晚期原生型”两种成藏模式。In recent years,the oil and gas exploration of the Wuyunting structure in the Pinghu slope belt of Xihu Depression of the East China Sea Basin has reported good commercial discoveries,but the fluid properties of wells A and B that have been drilled are quite different.Well A is a gas reservoir and well B is a reservoir.The hydrocarbon source,filling period and accumulation model of Wuyunting structure were analyzed by biomarker compound comparison,carbon isotope analysis and fluid inclusion analysis.It is believed that the Wuyunting structural oil is a normal mature crude oil,mainly derived from the local Ningbo 19 sub-sag,Pinghu Formation coal-series source rock.The upper part of Pinghu Formation is high-mature natural gas,mainly from the main source of the eastern main shoal of Ningbo 19 sub-sag,Pinghu Formation,and the middle section of Pinghu Formation.It is a normal mature natural gas,mainly derived from local source rocks.The fluorescence of the inclusions is light yellow oil and gas inclusions and colorless gas inclusions.The uniform temperature indicates that the Wuyunting structure mainly undergoes two phases of hydrocarbon charging,2 Ma and nowadays.The Wuyunting structure is rich in oil and gas resources,and the accumulation process is complex.Based on the hydrocarbon supply mode and the transport system,it is divided into two accumulation models:"dual-source lateral late secondary type"and"single-source vertical transport late native type".

关 键 词：西湖凹陷 油气源对比 流体包裹体 成藏模式 

分 类 号：P618.13[天文地球—矿床学] TE122.3[天文地球—地质学]