Abstract: Fuyu oil reservoir and Yangdachengzi oil reservoir (referred to as Fuyang oil reservoir)in northern Songliao Basin, located adjacent to the overburden source rocks of Member 1 of Qingshankou Formation, are typical tight oil reservoirs characterized with upper generation and lower storage, where oil and gas have not undergone long-distance migration, large-scale reservoirs are contiguously distributed without obvious reservoir boundaries. Based on a review of the exploration history of Fuyang oil reservoir over the past 60 years, the paper analyzes the key fields and directions of exploration at different stages. By using multi-scale and multi-type experimental testing results combined with logging data and seismic data, it was clarified that the whole-sag distribution and staggered contiguous distribution pattern of Fuyu and Yangdachengzi oil reservoirs are derived from the widely developed high-quality source rocks, dense fault belt transport systems, large-scale distribution of meandering river to shallow water delta sedimentary sand bodies, as well as the ideal "source-fault-reservoir" matching relationship formed under overpressure driving. At present, Fuyang oil reservoir has achieved a high degree of exploration in positive structures including Daqing placanticline, Weixing-Zhaozhou areas of Sanzhao sag, and Longhubao terrace, with large-scale distribution of tertiary reserves, demonstrating good exploration prospects. Two significant directions for the future exploration of tight oil below source rocks include Fuyu reservoir with relatively low exploration degree, represented by the syncline area of Qijia-Gulong sag, and the new tight oil enrichment zone of Yangdachengzi reservoir. Those fields are worthy of increasing exploration efforts, accelerating exploration progress, and strengthening technical breakthroughs. The research results can provide a theoretical basis for increasing reserve and production of tight oil on a large scale in northern Songliao Basin.

Key words: northern Songliao Basin, tight sandstone oil, Fuyang oil reservoir, enrichment and accumulation, new field, resource potential

摘要： 松辽盆地北部的扶余油层和杨大城子油层(统称扶杨油层)紧邻上覆青山口组一段(青一段)烃源岩,油气未经长距离运移,呈大面积连片成藏且无明显油藏边界,是典型的"上生下储"式致密油藏。通过回顾扶杨油层60多年的勘探历程,梳理了不同阶段的勘探重点与方向;采用多尺度及多类型的实验分析结果,结合测井数据与地震资料,明确了广覆式发育的优质烃源岩、密集成带的断裂输导体系、大面积分布的曲流河—浅水三角洲沉积砂体,以及在超压驱动下形成的良好"源-断-储"匹配关系,造就了扶余油层和杨大城子油层中致密油呈满凹分布、错叠连片分布。目前,扶杨油层在大庆长垣、三肇凹陷卫星—肇州地区、龙虎泡等正向构造的勘探程度较高,三级储量已大面积分布,展现出良好的勘探前景。未来源下致密油探索的两个重要方向包括勘探程度相对较低的扶余油层,以齐家—古龙凹陷向斜区为代表,以及杨大城子油层致密油富集新区带,这些区域值得加大探索力度、加快勘探进度、加深技术攻关。研究成果可为松辽盆地北部致密油的规模效益增储提产提供理论基础。

关键词: 松辽盆地北部, 致密砂岩油, 扶杨油层, 富集成藏, 新领域, 资源潜力