摘要
浅层新近系馆陶组—明化镇组为渤海的主力含油气层系。新构造运动是渤海新生代晚期发生的对油气成藏影响最为深刻的构造事件,对浅层油气成藏的影响远大于深层,控制了渤海浅层油气最终成藏。研究表明,新构造运动导致的凹陷晚期快速生排烃、多种类型圈闭发育、油气运移活跃等,整体上调整、控制了浅层油气藏的定型和分布,但对不同构造带浅层油气成藏的控制作用存在差异。根据构造位置和油气成藏特点,可将渤海浅层油气藏归为两大类:凸起区浅层油气藏、斜坡—洼陷区浅层油气藏。通过系统分析两类构造带浅层油气的成藏特点,明确新构造运动对两类构造带油气最终成藏的控制作用与富集模式差异,并构建了相应成藏模式。凸起区的浅层具有“晚期油源断层+浅层稳定储盖组合”的“台阶”型油气成藏模式;斜坡—洼陷区的浅层具有“洼中隆+晚期断层”“深层运移脊+晚期断层”两种“倒漏斗”型油气成藏模式。渤海浅层已进入了以岩性油气藏为主的勘探阶段,应加强新构造运动控制下的“晚期运移断层+岩性圈闭”组合勘探。
The shallow Neogene Guantao-Minghuazhen Formations are the main hydrocarbon-bearing series in Bohai Sea.The Neotectonic movements in the late Cenozoic were the most profound tectonic events in Bohai Sea,which had much greater influence on hydrocarbon accumulation in shallow formations than that in deep formations,and controlled the ultimate hydrocarbon accumulation in shallow formations.The study results show that the Neotectonic movements resulted in the rapid hydrocarbon generation and expulsion in the late sag subsidence period,development of various types of traps,and active hydrocarbon migration,which adjusted and controlled the ultimate hydrocarbon accumulation and determined the distribution of shallow oil and gas reservoirs in Bohai Sea.However,the control effect of the Neotectonic movements on hydrocarbon accumulation in shallow formations varied in various structural belts.Based on the structural position and hydrocarbon accumulation characteristics,shallow oil and gas reservoirs are classified into two major categories,i.e.,shallow oil and gas reservoirs in bulge area,and shallow oil and gas reservoirs in the slope-subsag area.By analyzing hydrocarbon accumulation characteristics of shallow oil and gas reservoirs in these two structural belts,the control effect of the Neotectonic movements on the ultimate hydrocarbon accumulation and enrichment patterns of shallow oil and gas reservoirs in different structural belts are identified,and the corresponding hydrocarbon accumulation patterns are established.Among them,the hydrocarbon accumulation in shallow bulge area is characterized by a“stepped”pattern controlled by“late fault connecting source rock+stable shallow reservoir-cap rock combination”.The hydrocarbon accumulation in shallow slope-subsag area shows“inverted funnel”pattern controlled by“uplift in subsag+late fault”and“deep ridge for gas migration+late fault”.At present,the exploration target in shallow formations in Bohai Sea is dominated by lithologic oil and gas reservoir,and the exploration should be focused on“late fault for gas migration+lithologic trap”combination controlled by the Neotectonic movements.
作者
米立军
徐建永
刘志峰
朱文奇
吴斌
Mi Lijun;Xu Jianyong;Liu Zhifeng;Zhu Wenqi;Wu Bin(CNOOC Research Institute Co.,Ltd.;National Engineering Research Center of Offshore Oil and Gas Exploration)
出处
《中国石油勘探》
CAS
CSCD
北大核心
2024年第1期92-105,共14页
China Petroleum Exploration
基金
中国海洋石油有限公司“十四五”重大科技项目“中国近海新区新领域勘探技术”(KJGG-2021-0300)。
关键词
新构造运动
渤海
浅层油气藏
凸起区
斜坡—洼陷区
成藏模式
“倒漏斗”型
Neotectonic movement
Bohai Sea
shallow oil and gas reservoir
bulge area
slope-subsag area
hydrocarbon accumulation pattern
inverted funnel type