松辽盆地富铀有机质建造发育特征及其对渗出型砂岩型铀矿的制约OACSTPCD

It is particularly important to study the black uranium-rich organic matter formations(UOMF)that provide uranium sources in the basin in exudative sandstone-type uranium deposits in Songliao Basin(SL).Based on a systematic review of occurrence horizon,distribution patterns,and uranium content of UOMF in the Songliao Basin,some conclusions can be draw as follow:Firstly,three sets of UOMFs in Songliao Basin,containing the bottom,middle and top UOMF,correspond to hydrocarbon source rock horizons of the lower Cretaceous,the bottom of the Qingshankou Formation,and the bottom of the Nenjiang Formation.Secondly,the top UOMF and the middle UOMF have a significant impact on uranium mineralization in the central and northern part of SL,while the southern SL is mainly constrained by the lower UOMF.Thirdly,Uranium industrial production boreholes are mainly located at the edge of the relatively high uranium content of UOMF connected by deep and large boundary faults,and this facts shows that the UOMF has a significant constraint on the sandstone type uranium mineralization in SL.It was inferred that black hydrocarbon source rocks not only provided certain reducing substances for uranium mineralization,but also may be an important potential uranium source for sandstone type uranium mineralization.This study can provide support for the"lower black"ore-forming elements for the prediction of exudative sandstone-type Uranium deposits,such as Yaojia Formation and Sifangtai Formation,which are dominated by the red formation,and can provide better guide for the exploration of exudative sandstone type uranium deposits in the Songliao Basin.