广东南雄盆地下俄井地区综合地球物理特征及铀成矿条件分析OA

Nanxiong basin is one of the typical representative red-bed basins in South China.In the early stage of geological exploration,several uranium mineralized points and radioactive anomaly zones were discovered on the surface of the Xia'ejing area.The mineralization was believed closely associated with the margin slope belt,deep stratigraphic undulations and structurs of the basin,and is hosted in light-colored sandstone.However,previous geophysical work in this area was mainly focused on radioactive exploration,which lacked systematic analysis of the deep geological environment and uranium metallogenic conditions of the basin,resulting in insufficient understanding for the further evaluation of metallogenic potential.Based on previous research results and geological cognitions,audio-frequency magnetotelluric sounding,high-precision magnetic survey and gravity survey this study carried out.Combined with the physical properties of major lithology,the development characteristics of boundary pluton and the locations of major faults were basically clarified.The distribution of deep strata and the deep burial depth were inferred,and the uranium metallogenic conditions of the study area were comprehensively analyzed.It is considered that the Xia'ejing area is located at the junction of the piedmont fault depression zone and the gentle area of the basin.The Nanxiong fault and concealed pluton extend relatively gently in the deep part.The light-colored sand layers in the study area show the characteristics of low resistivity.The above achievements and understandings indicate that the deep part and surrounding areas of Xia'ejing still have good uranium prospecting potential.