Information Extraction Of Remote Sensing Alteration And Comprehensive Metallogenic Prediction In Xiangshan Area, Jiangxi

Xiangshan area is located in the southwestern margin of Ganhang volcanic-rock metallogenic belt with faulted structure, magmatic rocks development, extensive metamorphism and complete stratum outcrops. There were lots of previous studies on regularity of ore formation, tectonic backgrounds and mineral types etc. of Xiangshan area and they found out that Xiangshan area had potential for searching for large uranium deposits.Based on research on existing data relating to the geology of the research area, this paper used OLI remotesensingdata to carry out information abnormity extraction of uranium mineralization alteration and conducted interpretation of liner-annular structure by the visual method. This paper utilized the “weights-of-evidence method” to carry out quantitative analysis on ore-finding information such as stratum, lineament, geochemical abnormity and alteration information abnormity as well as space distribution relationships of ore deposits(occurrence). Final favorable evidence factors were chosen by weighted values of various metallogenic information: U geochemical abnormity, favorable stratum units(Qbss1、ηγπk1s) lineament(degrees of central symmetry) and iron stained alteration abnormity etc. were used as geological variables for constructing a metallogenic prediction model; finally, by obtained values of posteriori probabilities, Xiangshan uranium deposits were predicted and metallogenic prospects were divided into different classes. Four uranium mineralization target areas were selected, in which there were 1 A-class metallogenic prospect, 1 B-class metallogenic prospects and 2 C-class metallogenic prospects. Metallogenic prospects were mainly controlled by faulted structures of NNE and NNW; remotely sensed alteration abnormity and various abnormal weightedvalues showed that mineralization within prospects were mainly related to iron-stained abnormity; the higher the class of an mineral resource potential area was, the greater the U geochemical abnormality value was; there were lots of ore deposits(occurrence) in the selected prospects, showing that outcomes of prediction had certain reliability and the selected mineralization target areas had work value for further research.