济阳坳陷渤南洼陷页岩油气形成条件研究

通过大量地震、钻井、测井、矿物、地球化学、物性资料分析,认为济阳坳陷渤南洼陷古近系沙一段、沙三下和沙四上亚段页岩分布面积广,有机质丰度高,有机质类型以Ⅰ—Ⅱ型为主,有机质成熟度分布范围宽,具备形成大量页岩油气的物质基础,三套泥页岩全岩矿物组成中粘土矿物含量低,脆性矿物含量高,以碳酸盐含量为主,利于页岩油气的开采。页岩中压力系数高,各类微孔隙、微裂缝发育,从而容易形成网状的油气储存体系,利于页岩油气的保存。含油、水饱和度分析资料显示,渤南洼陷沙三下亚段12上—13上层组页岩中具有较高的单位岩石含油气量,是页岩油气勘探的有利层段,其中的纹层状泥质灰岩是最有利的岩石类型,具有较好的页岩油气勘探前景。

Formation conditions of shale oil and gas in Bonan sub sag, Jiyang Depression

Through abundant data of seism, drilling, logging, mineral, geochemistry and physical properties, it is concluded that the shale of Paleogene Es1, Lower Es3 and Upper Es4 in Bonan sub sag, Jiyang Depression is characterized by wide distribution and high abundance, better types (mainly with type I and II) and wide maturity range of organic matter, with a material basis for the formation of shale oil and gas in a large scale. Meanwhile, the low content of clay mineral and high content of brittle mineral (mainly with carbonate) in the 3 sets of shale are favorable for the exploitation of shale oil and gas. In addition, the high pressure coefficient and the development of different micro pores and micro cracks in the shale are also favorable for the preservation of shale oil and gas, because the reticular storage system is easy to form under this condition. According to the oil and water saturation data, the upper of No.12 layer to upper of No.13 layer in the Lower Es3 formation are the favorable layers for shale oil and gas exploration in Bonan sub sag because of their high oil and gas content in unit rock. Especially, as the most favorable rock type, the lamiated argillaceous limestone could be effectively explored .