摘要
基于鄂尔多斯盆地安塞地区三叠系延长组长9致密油为近年来新发现的含油层位,认为其不具备形成大面积分布的准连续型致密砂岩油藏的形成条件,为此,以陕北斜坡中东部安塞地区长9油藏为例,探讨这种非准连续型致密砂岩油藏的形成机理与主控因素。研究结果表明：安塞地区长9油藏烃源岩质量较好、大面积分布但厚度较小,储层广泛分布,与烃源岩互层接触但非常致密,综合认为其成藏条件为较好—中等;早白垩世（120-100 Ma）时,长9暗色泥岩达到成熟阶段,油气生成并充注到长9致密砂岩储层中,近源运移并形成非常规油气聚集;长9油藏分布主要受控于烃源岩、储层和鼻状隆起背景控制,其中有效烃源岩分布范围控制油藏分布范围,储层展布及非均质性控制油气富集地区及含油层段,鼻状隆起背景对油气的富集高产具有重要的控制作用。
The Chang-9 member tight oil of Yanchang Formation of Triassic in Ordos Basin in Ansai area was discovered in recent years, and initial studies suggested that it does not possess the forming conditions to form a large area of distribution of the quasi-continuous tight sandstone reservoir. Taking the Chang-9 reservoir as an example of Ansai area in mid-eastern Shanbei slope, the non quasi-continuous tight sandstone reservoir forming mechanism and main controlling factors were discussed. The results show that Chang-9 reservoir source rock quality is good, and it has big area distribution but thinner thickness, widespread distribution reservoir and hydrocarbon source rocks interbedded touch but very compact, the integrated accumulation conditions are good—medium. In the early Cretaceous（120-100 Ma）, the Chang-9 dark mudstone reaches the stage of maturity, and then a large scale of oil and gas generated and injected into the Chang-9 tight sandstone reservoir, finally migrates to nearby reservoir at a short distance and forms an unconventional oil gas accumulation. The distribution of the Chang-9 oil reservoir is mainly controlled by its source rock, reservoir and the background of nose-shaped uplift. A distribution range of the effective hydrocarbon source rock controls the reservoir distribution, reservoir spreading and the heterogeneity control the enrichment area of oil and gas and the oil bearing intervals, and the background of nose-shaped uplift plays an important role in the control of the oil gas accumulation and production.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2014年第9期3127-3136,共10页
Journal of Central South University:Science and Technology
基金
陕西省自然科学基础研究计划项目(2013JM5007)
陕西省教育厅专项科研计划项目(12JK0491)
西安石油大学博士科研启动项目(2014BS38)
中国石油科技创新基金资助项目(2011D-5006-0103)
关键词
鄂尔多斯盆地
安塞地区
长9油层组
致密油
成藏机理
主控因素
Ordos Basin
Ansai area
Chang-9 member
tight oil
accumulation mechanism
main controlling factors
