摘要
利用重磁、地震、钻井等资料,结合前人研究成果,系统分析了南海中南部主要盆地新生代构造-沉积充填演化及油气地质条件,并进一步开展了烃源岩综合评价与油气成藏研究。南海中南部9个盆地可划分出中部伸展-裂离型、西部伸展-走滑型和南部伸展-挤压型等3大盆地群。中部盆地群经历了始新世—早中新世断拗期、中中新世漂移期和晚中新世—现今拗陷期演化阶段,以滨浅海—半深海沉积环境为主,发育陆源海相烃源岩,以Ⅲ型干酪根为主,主要发育下生上储式碳酸盐岩成藏组合;西部盆地群经历了晚渐新世—早中新世断拗期、中中新世反转期、晚中新世—现今拗陷期演化阶段,呈"早湖晚海"的沉积充填特征,发育湖相烃源岩和海陆过渡相烃源岩,以Ⅱ2—Ⅲ型干酪根为主;南部盆地群经历晚渐新世—早中新世断拗期、中中新世反转期、晚中新世—现今拗陷期演化阶段,发育三角洲-滨浅海沉积体系和海陆过渡相烃源岩,以Ⅱ—Ⅲ型干酪根为主。西部盆地群和南部盆地群近岸发育自生自储式砂岩成藏组合,远岸发育下生上储式碳酸盐岩成藏组合。本文研究成果进一步明晰了南海中南部盆地油气地质规律,可为下一步勘探决策提供技术支撑。
By using gravity magnetic,seismic and drilling data and combining with previous research results,this paper systematically analyzed Cenozoic tectonic-sedimentary filling evolution and oil and gas geological conditions in the main basins at the mid-southern South China Sea,and further carried out comprehensive evaluation on hydrocarbon source rocks and research on oil and gas accumulation. Nine basins distributing in the mid-southern South China Sea can be divided into three major basin groups： extension-dissociation type in the center,extension-strike-slip type in the west and extension-extrusion type in the south.Central basin group has experienced Eocene and early Miocene fault-depression period,drift period in the mid-Miocene and depression period from late Miocene to now,which was dominated by shallow shore-semi-deep sea environment; land-derived marine source rocks were developed,and type III kerogen played the controlling role,In the central basin group,carbonate reservoir in the accumulation combination of ＂lower generation and upper preservation＂was mainly developed. The western basin group experienced late Oligocene-early Miocene fault-depression period,mid-Miocene inversion period and depression period from late Miocene to now,showing accumulation characteristics of ＂early lake and later marine ＂,where lacustrine source rock and transitional source rock were developed,and II2—III type kerogen played the controlling role. The southern basin group experienced late Oligocene-early Miocene fault-depression period,mid-Miocene inversion period and depression period from late Miocene to now,where delta-shallow shore accumulation system and transitional source rocks were mainly developed and the II—III type kerogen played the controlling role. In the west basin group and the south basin group,the self-generation and self-preservation hydrocarbon accumulation combination was developed near the shore area,and the lower generation and upper preservation hydrocarbon accumulation combination was developed in the far shore area. This paper further clarifies oil/gas geologic distribution rule in mid-southern South China Sea and provides important technical support for future exploration decision-making.
作者
赵志刚
ZHAO Zhigang(CNOOC Research Institute Co. , Ltd. , Beijing 100028, Chin)
出处
《中国海上油气》
CAS
CSCD
北大核心
2018年第4期45-56,共12页
China Offshore Oil and Gas
基金
国家自然科学基金项目"南海深海地质演变对油气资源的控制作用(编号:91528303)"
"十三五"国家科技重大专项"曾母-北康盆地群油气地质条件研究与勘探方向选择(编号:2016ZX05026-004)"部分研究成果
关键词
南海中南部
盆地群
新生代
构造演化
沉积充填
成藏组合
mid southern South China Sea
basin group
Cenozoic
tectonic evolution
sedimentary filling
accumulation combination
