摘要：

松辽盆地北部中央坳陷白垩系泉头组扶余油层发育河流—浅水三角洲环境下形成的低渗透致密砂岩储集层。在已提交的探明储量中, 储集层孔隙度平均为11. 8％, 渗透率平均为2. 30×10^-3 μm², 以岩性油藏为主；剩余勘探目标以赋存于孔隙度小于10％、渗透率小于1×10^-3 μm², 储集层中的致密油为主。从烃源岩、构造、断裂和储集层4个方面阐述了扶余油层致密油成藏主控因素, 认为成熟烃源岩控制了研究区致密油分布范围, 构造高部位是油气运聚指向区, 北西向断裂带控制油气富集, 河道砂体控制致密油“甜点”区。采用类比法进行致密油资源潜力评价, 初步估算扶余油层致密油资源潜力为13. 09×10⁸ t, 是大庆油田资源接替的重要领域。

关键词: 致密油, 成藏主控因素, 资源潜力, 扶余油层, 泉头组, 白垩系, 松辽盆地

Abstract:

The Fuyu Layer of Cretaceous Quantou Formation in northern Songliao Basin developed a set of low permeable tight sandstone reservoirs formed in river to shallow-water delta environments. Proven reserves in the Fuyu Layer was preserved in reservoir rocks with average porosity of 11. 8％ and average permeability of 2. 30×10^-3 μm², lithology reservoir was the main reservoir type. The remaining exploration targets of the Fuyu Layer were tight reservoir with porosity less than 10％ and permeability less than 1×10^-3 μm² . The main controlling factors of the tight oil accumulations in Fuyu Layer could be listed as follows: The mature source rocks controlled the distribution range of tight oil;the structural heights were the target areas for petroleum migration and accumulation;the NW fault belts controlled the petroleum enrichment areas; the channel sand bodies controlled the tight oil “sweet spots”. Based on the analogy method, the exploration potential for tight oil accumulations in Fuyu Layer was evaluated, and the preliminary result is about 13. 09×10⁸ t tight oil to be proved, which would provide an important resource support for Daqing Oilfield.

Key words: tight oil, main controlling factors of accumulations, resource potential, Fuyu Layer, Quantou Formation, Cretaceous, Songliao Basin

中图分类号: 

• TE122.3＋1