黄河口凹陷油气成藏的主控因素

Major Control Factors of Petroleum Accumulation in Huanghekou Sag

黄河口凹陷是一个富生烃凹陷,目前已发现的油气藏及含油气构造大多具有埋深中浅层、原油密度中等、油质好、产能高等特点。纵向上发育多套含油层系,油气主要分布于新近系中。新近系油气成藏的主控因素为:近源、晚期快速成藏;浅水三角洲沉积体系为优质油气藏形成提供了空间;晚期走滑伴生断层是中央构造带油气富集的关键。

Huanghekou sag is prolific hydrocarbon sag, in which discovered reservoirs and oil-gas bearing structures are most characterized by medium to shallow buried depth, medium density of crude, good oil quality and high productivity. Multiple sets of oil- bearing sequences are found in vertical direction, mainly distributed in Neogene system. The major control factors of petroleum accumulation in Neogene are as follows： 1） near the hydrocarbon source and rapid accumulation in late period; 2） shallow-water delta deposit system provides the reservoir spaces for fbrming premium reservoir, and 3） late strike-slip associated fault is the key of oil-gas enrichment in central structure zone in Huanghekou sag.