断陷湖盆缓坡带岩性地层油藏模式及勘探实践——以冀中坳陷文安斜坡和蠡县斜坡为例

Lithostratigraphic Reservoir Models and Exploration Practice in Gentle Slope Zone of Rift Lacustrine Basins

冀中坳陷勘探潜力研究表明,文安斜坡和蠡县斜坡是岩性地层油藏勘探的有利区带。系统分析了富油气凹陷斜坡带岩性地层油藏形成具备的5个有利条件,构建了缓坡带砂体上倾尖灭、砂岩透镜体、河道砂岩性、地层超覆、地层不整合、构造—岩性和构造—地层等7种油藏模式,建立了在斜坡内带、中带和外带3种岩性地层油藏成藏序列。总结了文安斜坡外带中浅层河道砂岩性油气藏和蠡县斜坡中北段岩性地层油藏两个规模储量发现的主要研究思路、油藏控制因素和主要做法。对其他富油气凹陷缓坡带勘探具有一定的指导作用。

The exploration potential research of Jizhong Depression shows that Wen'an and Lixian are favorable lithostratigraphic reservoir exploration zones. The five advantages in the formation of lithostratigraphic reservoirs in gentle slope zones of petroleum-rich sags are systematically analyzed, seven reservoir models are set up including the up-dip pinch-out sandstone reservoir, the sand lens reservoir, the river sand lithologic reservoir, the stratigraphic overlap reservoir, the stratigraphic unconformity reservoir, structural-lithologic reservoir and structural-stratigraphic reservoir in gentle slope zones, and three lithostratigraphic reservoir accumulation series in the inner, central and outer slope zones are established. The main research route, the control factors of reservoirs and the major methods for the discovery of the two reservoirs, the mid-low channel sandstone reservoir in Wen'an slope outer zone and the lithostratigraphic reservoir in the northern-central Lixian slope zone, are summed up. It could have some guiding effect on the exploration in gentle slope zones of petroleum-rich sags.