柴北缘马海-大红沟凸起油气成藏模式与有利勘探目标

柴北缘马海-大红沟凸起油气成藏模式可概括为:深部为早期原生成藏,长期充注模式,具有多期(至少两期)油气运移成藏特征;浅部为早期排烃聚集,晚期次生成藏模式,具有晚期一次成藏的特征。古凸起区的两大构造运动、两套断裂体系所对应的圈闭形成期和成藏期是形成两种不同类型油气藏的关键。绿南山前构造带、马海-黄泥滩构造带、南八仙-东陵丘背斜带、以及马海构造的西南翼和东南翼的地层超覆区是今后勘探的重点目标。

Reservoiring patterns and favorable exploration targets in Mahai-Dahonggou salient in the northern edge of Qaidam basin

This paper summarizes the reservoiring patterns in Mahai Dahonggou salient in northern edge of Qaidam basin. Reservoiring pattern in the deeper part is of early primary accumulation with long period of hydrocarbon charging, which is characterized by multi stage (at least two stages) hydrocarbon migration and reservoiring. While Reservoiring pattern in the shallower part is of early expulsion and accumulation and late secondary reservoiring, which is characterized by late and once reserviring. Trap forming stages and reservoiring stages that are corresponding to the two major tectonic movements and two fault systems in the palaeo salient area are critical to the formation of these two different types of accumulations. Lunanshan piedmont structural zone, Mahai Huangnitan structural zone, Nanbaxian Donglingqiu anticlinal zone and the stratigraphic overlapping areas on the southwest and southeast limbs of Mahai structure are the major exploration targets in the future.