Characteristics of uranium-rich volcanic lava and prospecting direction of uranium deposits in Maquan Basin, Ganhang Belt

This paper is the research of uranium deposits prospecting direction.ObjectiveThe intermittent period of the Huanghu Ridge volcanic activity in Ganhuai belt, Jiangxi Province, China, produced a set of uranium-rich volcanic lava that is disposed in a layered manner within the Maqian Basin. The volcanic lava directly controls the spatial distribution of uranium ore bodies. Therefore, the study of the characteristics of uranium-rich volcanic lava is of great significance for analyzing the volcanic activity of this period, judging the source of mineralization, and indicating the direction of uranium exploration in the basin. Methods Based on the petrographic characteristics of the third section of the Yuhu Volcanic Group in the Zhujia Mine area of the Maqian Basin, this paper analyzes and tests the chemical element contents of the uranium-rich volcanic lava, the altered rocks, and the uranium ore stones. Results By summarizing the changes of chemical elements in the rocks and comparing and analyzing the characteristics of Andesite in adjacent areas, it is concluded that uranium-rich volcanic lava is Andesitic breccia lava and Andesite, which is rich in alkali, iron and titanium, and rich in light rare earth elements and large ionic lithophile elements(Rb, Ba, K).With the increase of uranium content in the rocks, the content of heavy rare earth elements in the ore of the Andesite series of potassium basalt lavas characterized by the loss of high field strength elements (Nb, Ta, Ti) continues to increase. It is concluded that the uranium-rich volcanic lava is formed by the volcanic eruption caused by the coupling of volcanic magma and deep uranium-bearing hydrothermal at the same period, and there is continuous uranium-bearing hydrothermal transformation in the later period. Conclusions Based on the characteristics of uranium-rich volcanic rocks, the search for concealed uranium-rich volcanic rocks of the Ehu Lake Late-Middle Period in the basin should be the focus of the next phase of uranium exploration work using geophysical prospecting methods, mainly magnetic survey.