页岩油是保障国家长期稳产和上产的重要战略资源,中国石油在鄂尔多斯、准噶尔、松辽等盆地均已取得重大勘探突破,发现不同岩相组合类型的页岩油.为确保我国原油2×108t稳产、提升国家能源安全保障能力,2021年中国石油加大页岩油勘探开发力度,取得了4项进展:(1)规模开发陇东页岩油,建成陇东页岩油百万吨整装示范区;(2)推进新疆吉木萨尔国家级陆相页岩油示范区与大庆古龙陆相页岩油国家级示范区建设,吉木萨尔页岩油产能跃上百万吨、古龙页岩油开启纯页岩型页岩油新篇章;(3)持续加大新区勘探力度,多个盆地勘探取得历史性突破;(4)理论、技术和管理持续创新,提质增效见到明显效果.总体来看,不同类型的页岩油还处于不同的勘探开发阶段,但距离实现规模效益开发目标还有差距.

针对近年准噶尔盆地玛东斜坡百口泉组岩性油气藏成藏机制及分布规律不清的问题,运用层序地层学与沉积相成因理论,精细剖析了YB4井区已发现油气的成藏特征与条件.揭示该区百口泉组油气藏主要为上倾尖灭岩性型,主要受控于“发育上倾尖灭的扇根河道或辫状河道砂体”、“上倾方向有泥石流封堵”、“上覆有高水位泥质盖层”和“下倾方向有沟通油源的断层”4个基本因素,其中“泥石流封堵”和“高水位泥质盖层”是其成藏的关键控制因素.该上倾尖灭岩性油气藏主要分布于百口泉组水进体系域上部的百二段顶部与百三段底部,是今后玛东斜坡区主要找油目标.

Based on lithology, well logs, seismic reflections and reservoir inversion, it is revealed that the sedimentary facies distribution of the lower Jurassic Sangonghe Formation in the southern Xiayan area of Junggar Ba-sin is mainly lake, fan delta and gravity flow.The provenances are mainly in the north and in the east of the study area.The fan delta front is developed in the eastern part of the study area, and the gravity flow is developed in the central and western regions.The semi-deep lacustrine facies is relatively developed on the top of second member and third member of Sangonghe Formation.The gravity flow mostly occurred on the top of first member of Sangong-he Formation.The shore-shallow lake mainly developed at the bottom of second member of Sangonghe Formation. In general, the water depth variation is coupled with the climate evolution of the period, which was from deep to shallow to deep, and climate is the main controlling factor of the sedimentary evolution in the study area.

近年来,准噶尔盆地夏盐凸起北部侏罗系三工河组多口井试获工业油流,表明该区良好的油气滚动勘探潜力.运用多条地震剖面、多口井的测井曲线及岩心资料对三工河组的断层特征及沉积储层特征进行综合研究,结合探井、评价井及开发井的试油、试采资料认为:夏盐凸起西部发育一近南北向的低幅度鼻状构造,其核部被近东西向及北东-南西向断裂相互切割,形成多个断块、断鼻构造;沉积微相揭示研究区为河控浅水三角洲前缘亚相沉积;成藏模式主要为“低凸断控聚集”成藏.基于以上认识,总结夏盐凸起的侏罗系油藏主控因素,并为夏盐凸起南部的勘探评价的提供了理论指导.