苏北后生—同生断陷盆地油气成藏规律研究  

Petroleum accumulation rules in hysterogenetic reconstructive-syngenetic rift basins,North Jiangsu Basin

作　　者：刘玉瑞[1] 

机构地区：[1]中国石化江苏油田科技处,江苏扬州225009

出　　处：《石油实验地质》2016年第6期721-731,共11页Petroleum Geology & Experiment

基　　金：中国石化科技项目"苏北盆地构造体系特征;演化与成藏研究"(P15077)资助

摘　　要：苏北盆地性质有多种不同观点,分歧影响了油气成藏深化认识。在分析前人盆地观、论据和问题后,根据识别先成、同生、后生盆地概念和唯一性标志,提出泰州组—阜宁组原型为大型拗陷盆地,经后期强烈改造成为"箕状形态"后生断陷盆地;叠加戴南组—三垛组同生断陷盆地,盐城组—东台组萎缩拗陷盆地,非继承性成盆形成了后生—同生断陷盆地。根据地化理论和实验数据,结合30年来勘探未熟油一无所获的事实,认为成烃遵循源岩干酪根晚期生烃模式,并呈现非均衡性成熟生烃和烃灶展布格局;不存在早期的未熟—低熟生烃带、双峰生烃和未熟—低熟油。指出盆地油源总体欠丰,源岩成熟有效供烃、断层多重性作用是控藏关键因素;后生断陷油气以侧运为主,油藏沿箕状烃灶呈扇形环带展布;同生断陷油气以垂运为主,构造油藏叠置烃灶上呈串珠状展出,复合油藏叠合呈裙边状展出;油气聚集呈非连续性的分布规律。There are different points of view about the type of North Jiangsu Basin, which affects the understanding of petroleum accumulation. According to the ideas and indicators of an eogenetic morphologic basin, hysterogenetic reconstructive basin and syngenetic rift basin, the North Jiangsu Basin was a hysterogenetic reconstructive-syngenetic rift basin which developed from a great depression during the Taizhou and Funing periods, and changed to a syngenetic rift basin of dustpan shape after strong deformation. Subsequently, the syngenetic rift basin and fading depression superimposed during the Dainan-Sanduo and Yancheng-Dongtai periods, respectively, finally forming a syngenetic-hysterogenetic rift basin. Based on geochemical theory and experimental data, and taking into consideration the fact that no success has been made in the exploration for immature oils in the past 30 years, we believe that hydrocarbon in the study area mainly developed from kerogen during the late stage, and hydrocarbon maturity and the kitchen distribution varied among areas. An early immature and lowmaturity hydrocarbon generation zone, doublepeak mode hydrocarbon generation, immature and lowmaturity oils do not exist. Source rocks in the basin have a low abundance of organic matter. Effective mature source rocks which can provide enough hydrocarbon and multiple roles of faults are the key controls for hydrocarbon accumulation. Oil and gas migrated mainly in a lateral direction, and reservoirs distributed of fan shape along halfgraben hydrocarbon kitchens in the hysterogenetic reconstructive basin. Petroleum migrated mainly in the vertical direction, structural pools lay above hydrocarbon kitchens like bead strings, and structurallithologic oil pools superimposed and distributed on the rim of syngenetic rift basin. Petroleum accumulations are discontinuous throughout the whole basin.

关 键 词：原型拗陷 后生-同生断陷 未熟油 晚期生烃 源-断控藏 苏北盆地 

分 类 号：TE121.1[石油与天然气工程—油气勘探]