摘要
珠江口盆地惠州26-6构造油气勘探的重大突破,是该盆地古潜山深层凝析气勘探的首个发现,但该区构造地质条件复杂,并且油气成藏要素之间耦合关系复杂,油气成藏主控因素不明制约了该区油气的进一步勘探。为了指导该区油气深化勘探,在系统解剖惠州凹陷26-6构造的基础上,根据构造、地震、地层等资料解释,结合钻井岩心、岩屑、薄片及流体包裹体分析,对惠州26-6油气藏古近系成藏主控因素进行了系统研究。研究结果表明:①古近系文昌组烃源岩最优,有机质类型以偏腐泥混合型为主,属于中等—很好品质烃源岩,恩平组次之,属于差—中等品质烃源岩,古近系烃源岩具备形成大型整装油气的成藏物质基础;②储层物性主要受沉积相类型控制,储层整体呈现较强非均质性,有利沉积相带主要为转换带三角洲前缘,具有“古近系转换带砂砾岩—古潜山风化裂缝带多期改造、规模成储”的特点;③研究区输导类型主要为断层、缝、砂体,由断缝和断砂的空间组合构成了立体网状输导格架,总体上呈现“切源断裂多期跨层输导,深缝浅砂侧向差异运移”的输导特点;④惠州26-6构造油气解剖结果表明,在充足的烃源和理想的封盖条件下,油气成藏主要受储集条件、圈闭条件和输导条件联合主控。结论认为,油气成藏主控因素的明确,为该区油气勘探指明了方向,为深化惠州油气勘探奠定了坚实的基础。
The great breakthrough of oil and gas exploration in 26-6 structure of Huizhou of the Pearl River Mouth Basin is the first discovery of deep condensate gas exploration in the buried hill of this basin.In this area,however,structural and geological conditions are complicated,the coupling relationships between hydrocarbon accumulation elements are complicated,and the main controlling factors of hydrocarbon accumulation are not determined clearly,which restricts the following oil and gas exploration in this area.In order to guide the further oil and gas exploration in this area,this paper systematically dissects the 26-6 structure of Huizhou.Then,the main factors controlling the formation of 26-6 oil and gas reservoir in Huizhou during the Paleogene are researched systematically based on tectonic,seismic,stratigraphic data interpretation,combined with core,cuttings,thin section and fluid inclusion analysis.And the following research results are obtained.First,the source rock of Paleogene Wenchang Formation is the best and it is classified as medium-very good source rock,whose organic matter is mainly sapropelic-prone hybrid kerogen type.The source rock of Enping Formation takes the second place and it is classified as poor-medium source rock.The Paleogene source rocks provide the material base for the formation of largescale monoblock oil and gas reservoirs.Second,the reservoir physical properties are mainly controlled by the types of sedimentary facies,and the reservoir is overall of stronger heterogeneity.The favorable sedimentary facies belt is mainly the delta front of transfer belt.And it is characterized by multi-stage reworking and large-scale reservoir formation of glutenite in Paleogene transfer belt-weathering fracture belt in the buried hill.Third,the migration pathways in the study area are mainly faults,fractures and sand bodies.The spatial combinations of fault-fracture and fault-sand body constitute a three-dimensional network migration framework,which is overall characterized by multi-stage bed across migration along source reaching faults and lateral differential migration along deep fractures and shallow sand bodies.Fourth,analysis on 26-6 oil and gas reservoir of Huizhou shows that hydrocarbon accumulation is mainly under the joint control of reservoir conditions,trap conditions and migration conditions when there are sufficient hydrocarbon sources and the sealing conditions are good.In conclusion,the determination of the main controlling factors of hydrocarbon accumulation points out the direction of oil and gas exploration in this area and lays a solid foundation for further exploration of the Huizhou.
作者
刘杰
徐国盛
温华华
史玉玲
蔡俊杰
徐昉昊
LIU Jie;XU Guosheng;WEN Huahua;SHI Yuling;CAI Junjie;XU Fanghao(School of Geosciences,China University of Petroleum(East China),Qingdao,Shandong 266580,China;Shenzhen Branch,CNOOC China Limited Shenzhen,Guangdong 518000,China;Chengdu University of Technology,Chengdu,Sichuan 610059,China)
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2021年第11期54-63,共10页
Natural Gas Industry
基金
中海石油(中国)有限公司科研项目“惠州26-6油气藏成因及成藏机理研究”(编号:CCL2020SZPS0138)。
关键词
珠江口盆地
惠州26-6构造
凝析气
油气成藏条件
成藏主控因素
勘探方向
Pearl River Mouth Basin
Huizhou 26-6 structure
Condensate gas
Hydrocarbon accumulation condition
Main controlling factors of hydrocarbon accumulation
Exploration direction
