基于原位方解石U-Pb定年与包裹体分析技术恢复储集层成岩-成藏过程——以准噶尔盆地南缘高泉地区白垩系清水河组为例  

Restoration of reservoir diagenesis and hydrocarbon accumulation process by calcite in-situ U-Pb dating and fluid inclusion analysis:A case study on Cretaceous Qingshuihe Formation in Gaoquan,southern Junggar Basin,NW China

作　　者：桂丽黎[1,2] 卓勤功 鲁雪松 杨文霞[1,2] 陈玮岩 吴海 范俊佳 贺银军[3] 曹日洲 余小庆[1,2] GUI Lili;ZHUO Qingong;LU Xuesong;YANG Wenxia;CHEN Weiyan;WU Hai;FAN Junjia;HE Yinjun;CAO Rizhou;YU Xiaoqing(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;CNPC Key Laboratory of Basin Structure and Hydrocarbon Accumulation,Beijing 100083,China;CNOOC Experimental Center,Engineering Technology Branch,CNOOC Energy Development Co.,Ltd.,Tianjin 300452,China;Wuxi Institute of Petroleum Geology,SINOPEC Petroleum Exploration and Production Research Institute,Wuxi 214126,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油天然气集团有限公司盆地构造与油气成藏重点实验室,北京100083 [3]中国海油能源发展股份有限公司工程技术分公司中国海油实验中心,天津300452 [4]中国石化石油勘探开发研究院无锡石油地质研究所,江苏无锡214126

出　　处：《石油勘探与开发》2023年第6期1209-1220,共12页Petroleum Exploration and Development

基　　金：国家自然科学基金委企业创新发展联合基金(U22B6002);中国石油天然气股份有限公司科技开发项目(2023ZZ0206,2021DJ0303,2021DJ0105,2021DJ0203)。

摘　　要：准噶尔盆地南缘深层成岩-成藏复杂性制约了其下组合油气勘探的进程。以准噶尔盆地南缘四棵树凹陷高泉构造油气藏为例,在白垩系清水河组储集层岩相及成岩作用分析的基础上,通过原位方解石U-Pb定年和流体包裹体分析技术,标定盆地热演化史,刻画高泉构造下组合油气成藏过程。研究表明,储集层中发育两期方解石胶结和3期油气充注,方解石形成年龄分别为(122.1±6.4),(14.2±0.3)~(14.4±1.0)Ma,油气充注事件为距今14.2~30.0 Ma低熟油充注,距今14.2 Ma以来成熟原油充注和距今2 Ma以来高熟天然气充注,油气藏以成熟油和高熟天然气充注贡献为主。距今2 Ma以来受喜马拉雅晚期南北向挤压冲断构造活动的影响,高泉构造圈闭发生了调整,主要成藏期有效圈闭规模明显减小,导致构造中低部位油气显示相对较弱,说明关键成藏期的圈闭有效性控制该区下组合的油气富集与分布。储集层方解石U-Pb定年技术和流体包裹体分析技术耦合,为精细刻画中国中西部复杂构造带的复杂成岩-成藏过程提供了有效方法。The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts the process of hydrocarbon exploration in the lower reservoir assemblage.The lithofacies and diagenesis of reservoirs in the Cretaceous Qingshuihe Formation in the Gaoquan structure of the Sikeshu Sag,southern Junggar Basin were analyzed.On this basis,the thermal evolution history of the basin was calibrated using calcite in-situ U-Pb dating and fluid inclusion analysis to depict the hydrocarbon accumulation process of the lower reservoir assemblage in the Gaoquan structure.The Qingshuihe Formation reservoirs experienced two phases of calcite cementation and three phases of hydrocarbon charging.The calcites are dated to be 122.1±6.4 Ma,14.4±1.0 Ma,and 14.2±0.3 Ma.The hydrocarbon charging events occurred at around 14.2–30.0 Ma(low-mature oil),14.2 Ma(mature oil),and 2 Ma(high-mature gas).The latter two phases of hydrocarbon charging contributed dominantly to the formation of reservoirs.Due to the tectonic activity of S-N compressive thrust in the late Himalayan since 2 Ma,the traps in the Gaoquan structure were reworked,especially the effective traps which developed in the main reservoir-forming period decreased significantly in scale,resulting in weak hydrocarbon shows in the middle-lower part of the structure.This indicates that the effective traps in key reservoir-forming period controlled hydrocarbon enrichment and distribution in the lower reservoir assemblage.Calcite U-Pb dating combined with fluid inclusion analysis can help effectively describe the complex diagenesis and hydrocarbon accumulation process of structural zones in the central-west part of the basin.

关 键 词：流体包裹体 原位方解石U-Pb定年 成岩序列 成藏时间 四棵树凹陷 准噶尔盆地南缘 白垩系 清水河组 

分 类 号：TE319[石油与天然气工程—油气田开发工程]