二连盆地芒来矿床砂体的非均质性与铀成矿关系研究

Study on the Relationship of Sand-body Heterogeneity to Uranium Mineralization in Manglai Deposit,Erlian Basin

芒来地段位于巴彦乌拉铀矿床西部,近年来随着勘查工作的不断推进,在该地段落实了中型规模铀矿床。在对芒来矿床矿体分布规律的研究中发现,铀成矿与赛汉组上段砂体的非均质性有一定的关系。统计钻孔含矿砂体与隔水层,在平面和垂向上均表明非均质性与铀成矿的关系密切。平面上砂体表现为西侧厚,东侧薄,具有由主干辫状河道向分支河道迁移的特征,铀矿化多出现在砂体厚度45~65 m,含砂率60%~70%,砂体由厚变薄的区域。垂向上,铀矿化多出现在隔层层数少,厚度薄地区,当隔层数为4~6层,厚度25~40 m时,最有利于铀成矿。

Manglai is located in the western part of Bayanwala uranium deposit.With the continuous advancement of exploration work,a medium scale sandstone-type uranium deposit was discovered in this area.A study on the distribution law of ore body in the northwest of Manglai found that the horizontal and vertical heterogeneity of sand bodies in the Upper Member of Saihan Formation affects uranium mineralization to some extent.Based on the spatial distribution characteristics of the ore-bearing sand bodies and the statistics of the aquifer and confining layer,the sand body was found thick on the west side and thin on the east side horizontally and has the characteristics of migration from the main braided channel to the branch channel,uranium mineralization occurs mostly in the sand body of 45~65 m thick and 60%~70%sand content where the thickness changes from thick to thin.In vertically,uranium mineralization mostly occurs in the areas where the confining layers are less in number and thin in thickness,the most favorable condition is of 4-6 layers and 25~40 m thick.