鄂尔多斯盆地中、古生界矿物组合与油气富集研究

鄂尔多斯盆地古生界与中生界是重要的油气储层,矿物岩石组合特征研究表明,组合类型与油气富集存在明显相关性。以石英砂岩为主的岩性组合主要形成于三角洲平原及三角洲前缘分流河道,物性好,提供了良好的储集空间。以铁白云石为主的含铁自生矿物组合形成于成岩晚期,配合合适的构造活动,可形成岩性圈闭。以浊沸石为主的沸石类自生矿物组合不但易溶能改善储集性能,而且与砂体边缘未被溶蚀区配合遮挡可组合成岩性圈闭。以薄膜状自生绿泥石为主的粘土矿物组合,对于储集性能起到双重作用。

Study on Relationship between Mineral Associations and Hydrocarbon Enrichments in Paleozoic and Mesozoic in Ordos Basin

Paleozoic and Mesozoic Erathems in Ordos Basin are important hydrocarbon-bearing reservoirs.Researches on characteristics of mineral rock association show that there is a great interdependency between gas oil enrichments and types of association.Lithic associations composed chiefly of quartzose sandstones were developed in delta plains and delta distributary channels with good physical properties to provide available reservoir space.Aauthigenic minerals associations made up mainly of ankerites were formed in late stage of diagenesis,which favor to create lithological trap associated with tectonic evolutions.While associations consisted principally of zeolites not only can improve the reservoir performance for their diffluent properties,but also form lithological trap incorporated with sealing of areas without corrosion at the margin of sand body.Associations contained mostly of film hydrosialites play double-faced roles in influencing reservoir performance.