Geochemical Characteristics And Prospecting Predictions Of 1:50000 Stream Sediments In Jiangma Area,Geji County,Tibet

Jiangma area is located in the western part of the Tibetan Plateau,and its administrative division is under the jurisdiction of Geji County,Ali,Tibet.The geotectonic of the study area is mainly located in the western Bangongco-Nujiang Suture Zone,which stretchs over Gangdisi magmatic arc and South Qiangtang arc-basin system tectonic units.Stratum in the study area are simple,mainly include Nawuco ophiolitic mélange Group,Mugagangri Group,Quse Formation,Shamuluo Formation,Qushenla Formation,Niubao Formation,etc.Magmatic activity is intense in the area,including late Triassic-early Jurassic ophiolites,early Cretaceous volcanic rocks and intrusive rocks.The structure in this area was well developed and the tectonic framework in this area was controlled by the NW-SE and the NWW-SEE faults.It belongs to the western Bangongco-Nujiang metallogenic belt,which has a copper-gold polymetallic metallogenic geological background and favorable metallogenic geological conditions.Based on the analysis and study of the measured data of 1:50000 stream sediments in Jiangma area,16 elements of Au,As,Sb,Hg,Cu,Pb,Zn,Ag,W,Sn,Mo,Bi,Cr,Co,Ni and Cd in the stream sediments were studied.The contents and spatial distribution characteristics of elements in the stream sediments were analyzed,and the main metallogenic elements in the study area were summarized.The characteristics of symbiotic assemblages of elements in sediments were analyzed and studied.Geochemical anomalies of stream sediments in Jiangma area were extracted,based on Unconventional statistics,Subregion contrast filtered through outliers and Double-window moving average,respectively.Contrasted and comprehensive analysed these geochemical anomalies,the double-window moving average method is selected as the abnormal information extraction model.Combined with the characteristics of metallogenic geological background,10 synthesis anomalies have been delineated by this method,comprising 5 class A and 5 class B anomalies.The synthesis anomalies of class A were explained and evaluated.Based on the synthesis anomalies,combined with the geological background,geophysics,remote sensing of the study area,2 ore prospect areas are defined in the study area,and 5 prospecting targets with.Moreover,we consider that epithermal porphyry copper-gold deposit and orogenic gold deposit are the haloes for the mineral deposits.This paper provides necessary and valuable basic geological information for the next mineral geology work in the study area,and also provides ideas and directions for regional mineral geology work.