鄂尔多斯盆地席麻湾地区延9地层油气分布控制因素分析

Regularity of petroleum accumulation and ditribution in Ximawan area of the Ordos Basin

席麻湾地区延9油藏类型主要为岩性—构造油气藏,其储量丰富,集中分布在工区南部及西南部;属于古生新储油藏,但生储盖配置较差。通过对席麻湾地区延9地层油气分布控制因素分析,认为沉积微相、构造、渗透性砂体以及油源是控制油气分布的主要因素。沉积微相控制着砂体的展布,渗透性砂体与构造的匹配是形成油藏的必要条件;圈闭距离油源近并位于油气运移的方向上是控制油气分布的重要因素。

Y9 reservoirs in Ximawan area are mainly lithologie -- structural trap, which accumulately distributed in southen and west -- southen of the reaserch area, and its volume of oil is very abundance. The reservoirs belong to palaeo -- generated and newly--stored type, but its configuration of source-- reservoir -- caprock is worse. The dominant controlling factors of hydrocarbon distribution include sediment microfacies, structure, permeable sand body and oil sources through the analysis of Y9 stratigraphy in Ximawan area. The sediment microfacies controll the distribution of sand body. It is one of the necessary condition for the formation of reservoir that the permeable sand body match with the structure. Another significant factor is the less distance between trap and oil source, and the trap must locate in the migration pathway.