Application of Geostatistical Tools to the Geochemical Characterization of the Peloritani Mts (Sicily, Italy) Aquifers

Sources of groundwater contaminants in inhabited areas, located in complex geo-tectonic
contexts, are often deeply interlocked, thus, making the discrimination between anthropic and natural
origins difficult. In this study, we investigate the Peloritani Mountain aquifers (Sicily, Italy), using
the combination of probability plots with concentration contour maps to retrieve an overall view of
the groundwater geo-chemistry with a special focus on the flux of heavy metals. In particular, we
present a methodology for integrating spatial data with very different levels of precision, acquired
before and during the “geomatic era”. Our results depict a complex geochemical layout driven
by a geo-puzzle of rocks with very different lithological natures, hydraulically connected by a
dense tectonic network that is also responsible for the mixing of deep hydrothermal fluids with the
meteoric recharge. Moreover, a double source, geogenic or anthropogenic, was individuated for
many chemicals delivered to groundwater bodies. The concentration contour maps, based on the
different data groups identified by the probability plots, fit the coherency and congruency criteria
with the distribution of both rock matrices and anthropogenic sources for chemicals, indicating the
success of our geostatistical approach.