松辽盆地东北隆起区砂岩型铀矿成矿条件分析

ANALYSIS ON THE ORE-FORMING CONDITIONS OF THE SANDSTONE TYPE URANIUM DEPOSIT IN THE NORTHEAST UPLIFT OF SONGLIAO BASIN

运用水成矿理论,对松辽盆地东北隆起区砂岩型铀矿成矿的铀源、构造、沉积、水文地质、古气候等条件进行了分析,认为该区具有良好的砂岩型铀矿成矿地质条件.具体表现在区内存在受构造运动影响地层隆起遭受剥蚀的构造天窗,在盆地边缘发育向南西倾斜的斜坡带;有利铀成矿的河流相、三角洲相砂体发育;泥岩-砂岩-泥岩结构层发育良好,有含水透水层和隔水层;补-径-排机制较完善,水动力条件较好,具有渗入型自流水盆地特征.该区具有良好的勘探前景.

With the theory of hydrogenic uranium deposit, the conditions of uranium source, geological structure, hydrology, sedimentation and paleo-climate for the metallogenesis of sandstone type uranium deposits in the northeast uplift of Songliao Basin are analyzed. The following geological conditions are considered favorable for the metallogenesis of sandstone type uranium deposits in this area： Influenced by tectonic movements, stratum uplifting and erosion, a structural inlier is formed in the area; A SW-trending slope belt is developed in the margin of the basin; The well developed sand bodies of fluvial facies and delta facies are deposited; an interlayer zone of mudstone-sandstone-mudstone is developed with permeable bed and impermeable bed; The supply-passage-discharge system is complete with favorable hydraulic condition and the characteristics of secondary seeping artesian basin. As a result, the prospects of uranium in the northeast uplift of Songliao Basin are encouraging.