伊犁盆地北缘表生热液成因砂岩型铀矿勘探前景及找矿方向

Prospecting Potential and Range of Reconnaissance of Supergenetic Sandstone Type Uranium Deposit on the Northern Margin of the Ili Basin

伊犁盆地南缘砂岩型铀矿床多见,但近年来盆地北缘铀矿勘探进展不大。通过野外调查,对伊犁盆地北缘苏拉宫等地侏罗系地质剖面观察与采样发现,盆地北缘砂岩露头中烧变岩常见,经测试发现局部成熟度较高的煤层出现铀异常。因此认为伊犁盆地北缘的侏罗系可能存在与南缘类似的表生热液成因砂岩型铀矿床,其与侏罗系煤层在新生代自燃有关,下一步的勘探方向应以烧变岩作为找矿标志,以与烧变岩联通的渗透性砂岩层作为勘探目标。伊犁盆地北缘构造运动(及其形成的褶皱构造)和新生代水系流向是决定表生热液储铀砂岩分布的关键因素,由此预测了伊犁盆地北缘砂岩铀矿的勘探远景区。

The southern margin of the Ili basin is rich in sandstone type uranium deposits, while few uranium minerals have been found on the northern margin of the Iili basin. Recently, some uranium anomalies are found out in the Jurassic coal measure with high index of maturation on the northern margin of the Ili basin. Accordingly, supergenetic sandstone type uranium deposit, perhaps, may be found out in the Jurassic coal-bearing formation related to coal spontaneous combustion on the northern margin of the Ili basin. Burnt rock and associated sandstone with high seepage rate may be considered as ore criteria.