Discussion on Metallogenic Conditions of Sandstone-type Uranium Deposits in Upper Cretaceous Yaojia Formation in Changling Area,Central Depression,Songliao Basin
In recent years,large-scale sandstone-type uranium deposits have been discovered in Kailu Depression and the southwest uplift belt of Songliao Basin.Searching correspondent deposit in same target horizons with similar metallogenic condition the central depression become an urgent and important question problem.With the guidance of sedimentology and uranium mineralization theory and the secondary utilization of oilfield data,this paper comprehensively analyzed the metallogenic conditions of sandstone type uranium deposit in Changling area,southern Songliao Basin.Changling area is stetted on an anticlinal structure,which is gentle in the SN extending slope,and steep in the EW extending slope.Near the northwestern steep slope,a series of faults developed along the NW direction,which may connect the structural skylight and make the uranium-containing oxygen water easily circling deep.The main uranium source body in the study area is granite in the western erosion source area,with high U content and high leaching rate,which provided abundant external uranium source for uranium mineralization.The subaqueous distributary channel microfacies of shallow-water delta front subfacies were mainly developed in the first member of Yaojia Formation,and the channel sand body has good connectivity and long extension distance.Pyrite with asphalt,color fading of the permeable sandstone by hydrocarbon fluid and limoization,hematitization in sandstone,indicate that the K2y1 developed a good redox condition.The comprehensive analysis shows that area near well Qs2 in Changling area is prospective to form Ⅰ-type sandstone type uranium deposit,and area near well Qs4 is prospective for the Ⅱ-type sandstone type uranium deposit.
metallogenic conditionssandstone-type uraniumYaojia FormationChangling area
万方数据
维普
