摘要
在分析南美北部前陆盆地重油成藏特征的基础上，总结各盆地重油成藏的主控因素，探讨其勘探前景。南美北部前陆盆地重油的烃源岩为上白垩统浅海相泥岩，储层为白垩系和第三系浅海三角洲相砂岩。重油成藏具有平面上呈带状分布、生烃条件优越、主要储层单一、埋藏较浅、运移距离长、以非构造油藏为主和稠变作用强的特征。重油成藏在宏观上受烃源岩、构造背景和稠变作用的控制。各盆地的主控因素又稍有不同：EV盆地的成藏主控因素为运移通道和中新统砂岩的分布；LB盆地为渐新统砂岩和局部盖层的分布；POM盆地为上白垩统砂岩和区域性盖层的分布。研究认为，南美北部前陆盆地的重油成藏条件有利、资源丰富、勘探潜力巨大。对于未来的重油勘探，以LB盆地的勘探潜力最大，EV和POM盆地次之；以第三系为主要勘探层系；以前陆斜坡带深度范围为61～2 667 m的构造地层圈闭为主要勘探目标。
The main controlling factors and exploration potential of northern South America were summarized through the analysis of heavy oil accumulation features in the foreland basins. The source rock of heavy oil in northern South America foreland basins is Upper Cretaceous shallow marine shale. Reservoirs are Cretaceous and Tertiary shallow marine - delta sandstones. The accumulation of heavy on has the characteristics of banded distribution, excellent source rock, single main reservoir, long distance migration, shallow burial, mainly of non-structural reservoirs and strong viscosifying mechanisms. The accumulation of heavy oil in northern South America was macroscopically controlled by the source rock, structural background and viscosifying mechanism. Each basin has different controlling factors. The migration pathway and distribution of Miocene sandstone, the distribution of Oligocene sandstone and local seals, and the distribution of Upper Cretaceous sandstone and regional seals are the main controlling factors in East Venezuela Basin, Llanos-Barinas Basin and Putumayo-Oriente-Maranon Basin respectively. The study suggests that the accumulation conditions are favorable for heavy oil in the foreland basins of northern south America, with rich heavy oil resources and great exploration potential. Llanos-Barinas Basin has the greatest heavy oil exploration potential, East Venezuela Basin and Putumayo-Oriente-Maranon Basin followed. Tertiary are the main exploration strata. Structure-stratigraphic traps in the foreland slope within depth of 61 - 2667 m are the main exploration targets.
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2014年第3期134-144,共11页
Earth Science Frontiers
基金
国家油气重大专项(2011ZX05028)
中国石油天然气股份有限公司重大科技专项(2013E-0501)
关键词
成藏特征
主控因素
重油
勘探前景
前陆盆地
南美北部
accumulation characteristics
main controlling factors
heavy oil
exploration potential
foreland basin
Northern South America
