鄂尔多斯盆地西南缘延长组长8段低充注油藏成藏模式——以环西—彭阳地区为例  

Hydrocarbon Accumulation Patterns of Chang 8Low-Charging Oil Reservoirs in Southwestern Margin of Ordos Basin:Taking Huanxi-Pengyang Area as an Example

作　　者：张晓磊[1] 唐颖 李卓奕 杨艳宁 崔一凡 任宇晖 韦明丹 ZHANG Xiaolei;TANG Ying;LI Zhuoyi;YANG Yanning;CUI Yifan;REN Yuhui;WEI Mingdan(Researcher Institute of Exploration and Development,PetroChina Changing Oilfield Company,Xi′an,Shaanxi 710018,China;State Key Laboratory of Continental Dynamics,Northwest University,Xi’an,Shaanxi 710069,China;Key Laboratory of Beijing City for Unconventional Natural Gas Geological Evaluation and Development Engineering,Beijing 100083,China;College of Petroleum Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China;The University of Manchester,Manchester,UK M139PL;Sixth Oil Production Plant,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi 710020,China)

机构地区：[1]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [2]西北大学大陆动力学国家重点实验室,陕西西安710069 [3]非常规天然气地质评价与开发工程北京市重点实验室,中国北京100083 [4]西安石油大学石油工程学院,陕西西安710065 [5]曼彻斯特大学,英国曼彻斯特M139PL [6]中国石油长庆油田分公司第六采油厂,陕西西安710020

出　　处：《西安石油大学学报（自然科学版）》2023年第1期31-44,共14页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：中国石油科技创新基金(2020D-5007-0202);陕西省重点研发计划“小分子可循环自清洁压裂液研发及产业化推广”(2022ZDLSF07-04);西北大学大陆动力学国家重点实验室开放课题基金(20LCD09);中国地质大学(北京)省部级重点实验室开放基金(20210102)。

摘　　要：为了厘清鄂尔多斯盆地西南缘环西—彭阳地区长8油藏的成藏机理,通过储层物性分析、烃源岩评价、流体包裹体分析和自生伊利石同位素测年等手段,明确成藏动力机制及成藏过程,并在不同地区油藏充注程度差异性对比的基础上,通过构造演化史、埋藏史、石油充注史研究,明确油藏分布控制因素。研究表明:长8油藏含油饱和度低,油藏分布呈南北分区的特征;低生烃强度耦合较强的储层非均质性是油藏低充注的主要成因;长7段剩余压力总体大于长8段,有利于长7段的烃向长8段充注;油气充注主要发生在早白垩世末期和晚白垩世早期(110~95 Ma);23 Ma以来,喜山期构造运动对西南区域油气聚集起到调整或破坏作用,北部为正常一致型,南部为早充注晚调整型;南北区成藏模式不同,北部环西地区以侧向输导运移成藏为主,南部彭阳地区以垂向运移成藏为主。经综合分析,鄂尔多斯盆地环西—彭阳地区长8油藏属于低生低压近距离低充注成藏模式。In order to deeply understand the hydrocarbon accumulation mechanism of the Chang 8 reservoir in Huanxi-Pengyang area, southwestern margin of Ordos Basin, the hydrocarbon accumulation dynamic mechanism and process of the reservoirare studied by means of reservoir property analysis, source rock evaluation, fluid inclusion analysis and isotopic dating of autogenetic illite.On the basis of the comparison of hydrocarbon charging difference of different regions, the control factors of reservoir distribution are clarified through the study of tectonic evolution history, burial history and hydrocarbon charging history.The research shows that the oil saturation of the Chang 8 reservoir is low, and its distribution is characterized by north and south areas.The lower the hydrocarbon generation intensity, the stronger the heterogeneity of the reservoir, which is the main cause of the low charging of the reservoir.The residual pressure of Chang 7 member is higher than that of the Chang 8 member, which is conducive to hydrocarbon charging to Chang 8 member.Hydrocarbon charging occurredmainly in the late Early Cretaceous and early Late Cretaceous(110~95 Ma) Since 23 Ma, Himalayan tectonic movement has adjusted or destroyed hydrocarbon accumulation in the southwest region.The northern part is a normal consistent hydrocarbon accumulation process, and the southern part is early charging and late adjustment process.The hydrocarbonaccumulation patterns of different regions are different.The Huanxi area in the north is dominated by lateral migration and accumulation, while the Pengyang area in the south is dominated by vertical migration and accumulation.The Chang 8 oil reservoir in Huanxi-Pengyang area of Ordos Basin has a hydrocarbon accumulation pattern with lowhydrocarbon generation intensity, lowpressure and shortcharging distance.

关 键 词：低充注油藏 成藏模式 生烃强度耦合储层非均质性 环西-彭阳地区 鄂尔多斯盆地西南缘 

分 类 号：TE122.1[石油与天然气工程—油气勘探]