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盆地充填序列和盆地演化关系密切。根据盆地充填序列和后期rrrrrrrrrn改造特征,将西胡里吐盆地演化划分为盆地发育阶段和盆后改造两大阶段,并论述了盆地发育阶段断陷期、扩张期、萎缩期、消亡期的演化特征以及盆地后期改造的特点。盆地发育过程中各个时期形成砂体的规模、连通性、空间展布、隔水泥岩的稳定性等特征决定了盆地内铀矿化类型和空间展布特征。断裂构造改善了盆地的水动力条件,为铀矿化的形成创造了条件。盆地充填后,长期隆升于地表遭受风化剥蚀,岩石中的孔隙没有因为压实作用而大量损失。砂岩中火山碎屑含量较高,在地表强氧化环境下发生蒙脱石化和沸石化,加大了地浸开采的难度。盆地内的铀矿化以潜水氧化带型为主,呈层状分布在盆地北部,在空间上具有一定的规模。通过对各种条件的综合分析,将盆地中部第二亚盆北缘作为下一步勘查首选目标。
The basin filling sequence is closely related to basin evolution. According to the filling sequence of the basin and the later transformation features, the evolution of the Xizhuli Tupai Basin is divided into two stages: the basin development stage and the basin reformation The evolution characteristics of faulted phase, expansion phase, atrophy phase and extinction phase in the basin development stage are discussed, and the features of the late stage of basin transformation are also discussed. The characteristics of the type, spatial distribution of uranium mineralization in the basin are determined by the characteristics of sandstone size, connectivity, spatial distribution and the stability of translucent shale at various stages in the process of basin development. The fault structure improves the hydrodynamic conditions of the basin and creates the conditions for the formation of uranium mineralization. After filling in the basin, the long-term uplift on the earth surface is subject to weathering and denudation, and the pores in the rock are not greatly lost due to compaction. The content of volcanic debris in sandstone is high, and montmorillonitization and zeolitization occur under the strong oxidizing environment of the surface, which increases the difficulty of earth leaching. The uranium mineralization in the basin is dominated by the submarine oxidation zone and is distributed in the north of the basin in a layered manner with a certain scale in space. Through the comprehensive analysis of various conditions, the northern margin of the Second Sub-basin in the central part of the basin is the preferred target of exploration.