The Establishment Of Active Trace Element Measurement Method And Its Application In Sandstone-type Uranium Exploration

With the development of exploration for sandstone type uranium deposits,the traditional geochemical methods face more challenge,there is a urgent need to establish a new method to find buried sandstone type uranium deposits which is invisible by traditional methods.Through the active part of surface elements to detect deep mineral information has achieved initial success,so it has become the focus of research in recent years.The purpose of this paper is to establish an analytical technique called "soil active trace element measurement" for buried sandstone type uranium deposits.Selection of technology route as shown : first of all investigate and survey is given to the domestic and foreign existing similar methods,and the three methods including the BCR method,the representative metal active state analysis method and one-step extraction method are conducted,so as to evaluate their advantages and disadvantages,the purpose of comparison for the three methods is to lay the foundation for the analysis of trace elements of activity measurement.On this basis,screening reagent combination sand testing analysis conditions was used to establish the "trace element activity measurement" analysis process,parallel test then was done,finally the "trace element activity measurement analysis technology was established.The analysis method was used to measure the more than 3000 samples in Heshituoluogai basin Poplar River depression.The results show that the relative error of the code sample and the relative error of more than 90% sample are within 30%,and the analysis data is reliable.Factor analysis subsequently is used to screen the principal factors which are closely related to sandstone uranium deposits and supergene geochemical conditions.The principal factors of F1 and F4 are particularly significant to geochemical exploration.The principal factor F1(La-Th-Be)represents the possible sources of material information in the region.Principal factor F4(U-MoGe)anomaly is closely related to deep sandstone uranium mineralization.In addition,the principal factor F2 is strongly related to the organic matter on the surface,principal factor,its distribution range is affected by the action of flowing water and deep mineral resources;while the other principal factors are not significant enough to be related to mineralization.The anomalies of U elements also indicate the possible favorable sites for mineralization and confirm each other with the F4 principal factor.While the ratio of U/Th also reflect the possible mineralization favorable areas.On the basis of this model,using sandstone uranium deposit geochemical anomaly model combining with the geological background of the basin and the analysis of the uranium source conditions,the possible uranium metallogenic prospect area of the basin is predicted.The central basin of poplar West Bank(Chapter I zone)and the area near Zhangergan area(Chapter II zone)was considered to be the most favorable prospect area.