Genesis of bleached zone in interlayer oxidation zone and its prospecting significance

This paper introduces some examples of bleached zone in interlayer oxidation zone at sandstone-type uranium deposits at home and abroad, and analyses the genesis of bleached zone both macroscopically and microscopically. Authors suggest that the bleached zone is originated from the reduction of oxidized sand bodies by reducing gas of oil-gas ascending from the deep after the formation of interlayer oxidation zone, that main uranium orebodies are located between bleached zone and zone of primary unaltered rocks. As the bleached zone is the result of secondary reduction of oxidized sandstone, it might be wrongly regarded as unaltered primary grey sandstone thus leading to the missing out of uranium orebodies. From the above discussion, a deduction could be made, that uranium orebodies may occur in V-depositional cycle further ahead to the north of explored area, at the area of exploration line No.253, the western area of Wukurqi deposit, and the area between exploration lines No.389-421, the middle of Wukurqi deposit