Structural evolution of the Roudný gold deposit, Bohemian Massif: a combination of paleostress analysis and review of historical documents

Abstract

The Roudný gold deposit, hosted by a large-scale NNE-SSW trending fault zone (the Blanice Graben), represents a type locality of low-fineness gold (Au-Ag) mineralization in the Bohemian Massif. In order to decipher its structural evolution, we performed a detailed analysis of brittle to brittle-ductile structures on outcrops and of structures described in unpublished historical materials. Three stress phases were distinguished: compressional, strike-slip, and extensional. Most hydrothermal veins originated during the strike-slip and extensional phases. Based on a comparison with the nearby Ratibořské Hory-Stará Vožice deposit, a representative of Ag-Pb-Zn vein type mineralization in the Blanice Graben, we conclude that the structural pattern of both ore deposits/mineralizations (Ag-Pb-Zn and Au-Ag) is compatible with the overall sinistral strike-slip evolution of the Blanice . Whereas most of the Ag-Pb-Zn veins represent typical extension veins/fractures, early gold-bearing quartz veins of the Roudný deposit were probably initiated as Riedel R' shears and were later reopened during the extensional phase.

Argentotetrahedrite-(Zn), Ag6(Cu4Zn2)Sb4S13, a new member of the tetrahedrite group

“…Argentotetrahedrite-(Zn) was also identified in samples collected from the mine dump in the southern part of the abandoned small deposit of Zvěstov (Stříbrnice), which is located 1200 m NNE from the village of Zvěstov. This deposit located 10 km SW of Vlašim, central Bohemia region, Czech Republic, is one of the small ore occurrences connected with the Blanice Graben, which represents an ~200 km long NNE–SSW trending crustal-scale brittle tectonic zone in the Moldanubian Unit, with minimal sinistral movement of ~17 km (Zachariáš and Hübst, 2012). The deposit consists of an irregular hydrothermal vein system ~1300 m long, with thickness ~20– 50 cm and a vertical extent (verified by a prospect borehole) of ~60 m (Nouza, 1988).…”

Geology and mineralization characteristics of Khamkeut Saen Oudom gold deposit, Bolikhamxai, Lao PDR

“…The Yilgarn, West Australia (Duuring et al, 2000), Hillgrove, New Southwest Australia (Ashley and Craw, 2004) and one part of Bohemian massif (Zacharias and Hübst, 2012) are high metamorphic rocks have higher values than KSO. Yuryang (Pak et al, 2005) and one part of bohemian massif (Zacharias and Hübst, 2012) are low grade metamorphic rock which have similar range to KSO (Fig. 5.1).…”