Extraction And Evaluation Of Vanadium Mineralization Anomaly Based On Multifractal Model In The Jiujiang,Jiangxi Province

The Jiujiang region in northern Jiangxi Province is well-known for its numerous black shale-type vanadium deposits,which have tremendous potential for vanadium ore formation.The area has rich geochemical data and a long research history,but less previous studies have been conducted on using geochemical sampling data to extract mineralization anomalies for guiding mineral exploration in the region.In this study,based on 1:200,000 stream sediment geochemical data,a combination of multivariate statistical analysis techniques and multi-fractal anomaly extraction models was used to study the spatial distribution patterns and enrichment areas of trace elements in the Jiujiang region.Mineralization-related combination element geochemical anomalies were extracted,and favorable ore-controlling stratigraphy(the Hetang Formation and Piyuancun Formation)and unfavorable ore-forming factors(intrusive rocks)were evaluated to determine the vanadium ore-forming potential of the region and to delineate favorable ore exploration targets.The results of the multivariate statistical analysis showed that vanadium(V),chromium(Cr),cobalt(Co),and nickel(Ni)were closely related to vanadium mineralization in the region.The distribution of each trace element did not follow a normal or lognormal distribution,but rather a fractal or multi-fractal distribution.Based on the anomaly interpolation results,the multi-fractal model performed better in extracting anomalies,and the combination of multiple elements was more helpful in guiding mineral exploration.Comparing the C-A fractal model and S-A fractal model,both models performed well in extracting geochemical anomalies,but the C-A fractal model was knowledge-driven and could automatically determine the anomaly threshold and delimit the local anomaly area(i.e.,high anomaly),which was helpful in delineating the high anomaly range when exploring for vanadium deposits.Therefore,the combination geochemical anomaly extracted using the CA fractal model was used to guide vanadium mineral exploration in the Jiujiang region.Based on the combination geochemical anomaly extracted by the C-A fractal model,the vanadium ore-controlling stratigraphy,and the distribution range of intrusive rocks in the region,potential vanadium ore-producing areas were delineated.The results showed that the known vanadium deposits and their deeper surroundings were the key exploration areas for the next step.In addition to the surrounding areas of known vanadium deposits,seven possible ore-producing targets have been delineated in the central and western parts of the study area,including three primary ore-producing targets(A-1,A-2 and A-3)and four secondary ore-producing targets(B-1,B-2,B-3 and B-4).