Geochemical associations and their spatial patterns of variation in soildata from the Marrancos gold—tungsten deposit: a pilot analysis

摘要

This paper discusses the results of a soil geochemical exploration surveyin the environs of the Marrancos gold—tungsten deposit, dealing with 144 samples oftopsoil, analysed for 53 chemical elements. At this initial stage of the project the mainobjectives were: (1) to identify associations between chemical elements; (2) toestimate spatial patterns of variation for such associations in the surficial materials.The associations were established using principal component analysis (PCA).Variography was used to obtain the theoretical model of spatial continuity of eachvariable. These models were used in the interpolation method (kriging) selected toestimate surficial dispersion patterns. The results of PCA and PCA mapping indicatedistinct distribution patterns for the metals related to the primary mineralogical orgeochemical association, as identified for this deposit. Based on the results, six of the53 chemical elements studied were selected to estimate spatial patterns of dispersionin the topsoil. This approach allows the recognition of the geochemical signature ofthe deposit, and the selection of several target areas for follow-up work. Several siteswere selected for water sampling (surficial and groundwater), and the soil samples tobe used in partial extractions are now defined.