New map representation of soil results in the environmental geochemical atlas of the Geological Survey of Brazil

Abstract

Since the sampling of the first twenty centimeters depth in top layer of soil sampling points, aiming at environmental studies, it was necessary to find a way to represent these results in the soil maps of the Environmental Geochemical Atlas of the Geological Survey of Brazil (SGB-CPRM). It should not increase the number of maps per Atlas, and should be understandable and accessible to professionals of several disciplines, besides being compatible with more than 15,000 samples, already collected by the environmental geochemistry and medical geology project (PGAGEM) of the SGB-CPRM since its beginning in 2003. After studying how British and Chinese researchers developed ways of representation for similar surveys in their own countries, it was chosen to make a single map, representing the two samples, the superficial (Top) being represented by colored and varied points and the subsurface (Sub) represented by a raster surface generated by IDW compatible with the previously performed samples. A map of the Federal District of Brazil is shown as an example of the defined model.