塔里木盆地北缘断褶带层间氧化带发育样式及砂岩铀矿找矿潜力

塔里木盆地北缘处于强断褶带，缺乏稳定平缓的斜坡带。以中侏罗统、上新统为主的砂岩型铀成矿目的层在断陷区、褶皱区发育不同的层间氧化带样式，形成的铀矿有所不同。已经发现的层间氧化带分为陡倾型和反转型。陡倾型层间氧化带定位于山间残留断陷盆地和山前断裂附近，多数地段氧化带已经剥蚀殆尽，局部有残留。反转型层间氧化带受盆内复背斜（或隆起）的抬升隆起影响使得层间氧化带发生反转掀斜，部分过渡带及铀异常体—矿体被剥蚀出地表。主要的铀矿体呈倒卷状，部分呈透镜状。综合分析表明，研究区铀成矿有利地段为断陷区、盆缘第一级褶皱露头区和隐伏的褶皱带。 

INTERLAYERED OXIDATION-ZONE STYLES IN FAULT-FOLD BELTS OF THE NORTHERN TARIM BASIN AND ITS CONTROLLING TO THE FORMATION OF SANDSTONE-TYPE URANIUM DEPOSITS

The northern rim of the Tarim basin was strongly deformed, forming series of fault-fold belts, where was lack of stable gentle slope zones which are generally regarded as favorable for the formation of sandstone-type uranium deposits. Most recently discovered sandstone-type uranium deposits hosted in Middle Jurassic and Pliocene are different because of various interlayer oxidation zone styles. The interlayer oxidation-zone styles could be divided into two different types, including steep dipping and inverse transformation. The former type of zones are usually situated in the intermountain residual fault basin, or near the piedmont faults. Most parts of this type of oxidation zones had been denudated and only partially preserved. The latter zones are generally controlled by the uplifting of anticlinorium in the basin. As a result, inversion tilting leads to part of the transition zone and uranium anomaly-bodies eroded out to the surface. Main uranium ore-bodies in these deposits behave as roll-back and part of lenticular in shape. Therefore, comprehensive studies suggest that the favorable uranium mineralization should probably be located at the sag areas, the edge of the first low fault-fold zones, and some other blind fault-fold belts.