鄂尔多斯盆地古生界盖层封盖性研究

A study of the Sealing Properties of the Palaeozoic Caprocks in Erduosi Basin

鄂尔多斯盆地古生界盖层主要为泥质岩、铝土岩、膏岩和致密碳酸盐岩。这些盖层若按成因分类,可分为陆源、化学和混合成因三类,其中以混合成因盖层的封盖能力最强。盖层的封盖能力主要受自身矿物组分和成岩作用的影响,而气藏的存在及其规模又受区域盖层和直接盖层的控制。

The Palaeozoic caprocks in Erduosi Basin are mainly argillaceous rocks,aluminous rocks,gypsum rocks and dense carbonate rocks. If it is classified according to their geneses,such caprocks can be di- vided into three types of terrigenous,chemical and mixing ones. The sealing ability of the mixing gene- sis caprocks is the strongest among them. The sealing ability of the eaprock is mainly influenced by its mineral composition and diagenesis,but the occurrence of the gas reservoir and its size are also con- trolled by regional caprock and direct caprock.