摘要
珠江口盆地番禺低隆起勘探潜力较大,但研究程度偏低,且局限于单个洼陷,缺乏断裂构造对洼陷沉积及源—汇体系影响的系统性分析,限制了后续勘探开发的进行。为厘清番禺低隆区断裂构造对洼陷沉积及源—汇体系的作用机制,基于最新三维地震数据和钻井资料,系统剖析了珠江口盆地番禺低隆区构造活动控制下洼陷的古近系源—汇响应关系及演化序列。研究表明:番禺低隆区新生代断裂活动在晚中生代的两期NE-NEE向和NW-NWW向先存断裂影响下表现为明显的分带性和分期性,早文昌期断裂控洼西部以NE-NEE向为主,东部以NW-NWW向为主,文昌期断裂活动强于恩平期;在先存断裂体系活化影响下,区内发育迁移型断裂控洼、组合型断裂控洼和继承型断裂控洼三种类型。区内源—汇系统以隆起区长英质花岗岩和古珠江水系为物源,陡坡断裂、缓坡转换断槽及反向断阶为搬运通道,半地堑洼陷为沉积区。早文昌期发育近物源供应为主、小湖盆大源区的源—汇系统;晚文昌期发育近-远源共存、大湖盆小源区的源—汇系统;恩平期发育西部远源、东部近源供给的大湖盆小源区的源—汇系统。整体上,高构造活动速率、低物源供给的晚文昌期,发育最优质的半深湖相烃源岩;而低构造活动速率、高物源供给的恩平组时期,广泛发育大型远源三角洲沉积砂体,垂向上形成最有利生储盖组合。
The exploration potential of the Panyu low uplift in the Pearl River Mouth basin(PRMB)is considerable.However,the level of research remains low and is limited to individual depressions,lacking systematic analysis of the impact of fault structures on the sedimentation of depressions and the source-sink system.This limitation hinders subsequent exploration and development activities.Therefore,this paper systematically analyzes the relationship and evolutionary sequence of the source-sink response under the control of tectonic activity in the Panyu low uplift area of the PRMB,based on the latest 3D seismic data and drilling information.The Cenozoic fault activity in the Panyu low uplift area exhibits significant zonation and periodicity under the influence of two existing fault systems,NE-NEE and NW NWW,during the Late Mesozoic.In the Early Wenchang period,the faulting controlled the depression,with NE-NEE direction dominating in the western region and EW direction in the eastern region,while the fault activity increased during the Wenchang period compared to the Enping period.Three types of fault-controlled depressions developed within the area:Migration-type,combination-type,and inheritance-type.The source-sink system in the area utilizes the felsic granite from the uplift area and the ancient Pearl River as the material source with steep slope faults,gentle slope transition trenches,and reverse fault steps acting as transportation pathways,while half-graben depressions serve as the sedimentation zones.In the Early Wenchang period,a source-sink system dominated by nearby material sources and large source areas developed in small lake basins;In the Late Wenchang period,a coexistence of nearby and distant material sources in the small source area of large lake basins occurred;And during the Enping period,a large lake basin system developed with distant sources in the western region and nearby sources in the eastern region.Overall,the highest quality semi-deep lake facies hydrocarbon source rocks developed in the Late Wenchang period characterized by high tectonic activity rates and low material source supply;Large-scale distant deltaic sedimentary sand bodies widely developed in the Enping Formation period marked by low tectonic activity rates and high material source supply,the source rocks and the sand bodies formed the most favorable vertically combination of source,reservoir and cap rocks.
作者
蔡嵩
郑金云
李振升
舒梁锋
靳瑶瑶
Cai Song;Zheng Jinyun;Li Zhensheng;Shu Liangfeng;Jin Yaoyao(CNOOC China Limited,Shenzhen Branch,Shenzhen 518054,Guangdong,China;CNOOC Deepwater Development Limited,Shenzhen 518054,Guangdong,China)
出处
《吉林大学学报(地球科学版)》
北大核心
2025年第5期1420-1433,共14页
Journal of Jilin University:Earth Science Edition
基金
中国海洋石油有限公司“十四五”重大科技项目(KJGG2022-0301)
中国海洋石油有限公司前瞻基础研究项目(KJQZ-2023-2001)。
关键词
番禺低隆区
先存断裂体系
断裂演化
断裂控洼
源—汇系统
烃源岩
珠江口盆地
Panyu low uplift
pre-existing faults
fault evolution
fault-controlled depression
source-sink system
source rock
Pearl River Mouth basin
