On the Geochemistry and Mineralogy of the Anthropocene

Since geochemistry and mineralogy have been reciprocally controlled, this work is meant to review the setting of a geochemical and mineralogical signal related to the Anthropocene strata. From geochemical viewpoint, a worldwide geochemical enrichment of the atmosphere, hydrosphere and pedosphere may be used as stratigraphic markers of the Anthropocene. For instance, global biogeochemical cycles of major nutrient elements, trace elements, emerging pollutants, and organic pollutants were recently modified during the Anthropocene due to human activities. In addition, some isotopes may be used as an isotopic signature of widespread human impact on the global environment. Several methods were developed to evaluate the scale of anthropogenic effect including the computation of some geochemical parameters such as enrichment and contamination factors, geoaccumulation index and pollution load index. To make a distinction between natural and anthropogenic pollution, a geochemical background levels should be used. In addition, statistical methods such as Principal Component Analysis (PCA) and Clustering Technique (CT) argued relevant to study Anthropocene samples. As examples of Anthropocene record in Tunisian polluted sites, we presented three cases. (1) Record of the Anthropocene based on heavy metals and PCA along a core from the coast of Sfax. (2) Record of the Anthropocene based on infrared and CT along a core from Sebkha El Guetiate, Gabes. (3) Polychlorinated Biphenyls (PCBs) previously detected at the surface of Bizerte lagoon was reinterpreted as proxy to set the Anthropocene strata in Tunisian wetlands. Added to the direct effects of human pollution, secondary effects such as the acidification of aquatic environment increase mobility of several trace elements, leading hence to a new generation of mineral species. During a small period from 2017 to the beginning of the 2020, a boom of the number of mineral species may be noticed in the approved list of new minerals. In this review, we catalog only 30 mineral species resulting from combination of the new human induced elements pumped within environment.