Geochemical Atlas – Erzgebirge and Vogtland

The distribution of Cadmium (Cd) in stream sediments is log normal with a slight tendency to left skewness. The median is 0.9 mg/kg and the arithmetic average is 1.7 mg/kg. The minimum concentrations are close to the detection limit of 0.005 mg/kg, the maximum values are to 84 mg/kg. Areas with gneiss hosted polymetallic vein deposits show significantly higher average Cd contents than granite massifs and Ordovician to Devonian metasedimentary rocks. Areas of Cd > 5 mg/kg are related to the Freiberg mining district and to an ESE adjacent area of approximately 10 km E-W extension that partially hosts Pb-Zn-Ag bearing veins. Other areas of similar concentration occur in the vicinity of stratiform Fe-Zn-Sn mineralisation of the Westerzgebirge Complex deposit, extending beyond the study area´s south-eastern tip at the Czech border. Areas with Cd > 3 mg/kg occur in Ordovician to Devonian metapelites and metabasites SW of Oelsnitz, e.g. in the vein districts of the central Erzgebirge (Annaberg-Buchholz, Ehrenfriedersdorf, and Marienberg-Wolkenstein), in the surrounding of the Sn-greisen deposits of Altenberg and Zinnwald-Cinovec, and near to the carbonate hosted stratiform Pb-Zn deposit of Rehefeld-Hermsdorf. Also, the polymetallic mineralisation of Mohorn-Grund with its remnants of mining activity coincides with elevated Cd levels. Furthermore, Ordovician metapelites of the northern Erzgebirge rim generally contain around or less than 1 mg/kg Cd. The lowest contents (Cd < 0.1 mg/kg) are related to the western part of the Eibenstock granite, whereas the neighbouring Kirchberg and Bergen granites do not contrast with their metasedimentary envelope.