Przestrzenne rozmieszczenie srebra w strefie kontaktowej utworów redukcyjnych z utworami utlenionymi (Rote Fäule) w rejonie złoża Cu-Ag Radwanice-Gaworzyce
Abstract
Spatial distribution of silver at the contact zone of reduced rocks with oxidized rocks (Rote Fäule) in the Cu-Ag Radwanice-Gaworzyce deposit.
A b s t r a c t. The characteristics of spatial distribution of silver minerals and Ag in ore minerals within the Lower Zechstein formations at the contact zone between reduced rocks and the Rote Fäule oxidized rocks are shown. All presented outcomes are on based on rock material taken from mining profiles and some archival boreholes in the Radwanice-Gaworzyce deposit area. These studies were used microscopic observations in reflected light and by microprobe analyses using the CAMECASX-100. In all analyzed profiles, oxidized rocks (enriched in hematite) were found, which occur at various levels of the Kupferschiefer series beneath the reduced zone enriched in ore minerals. Silver in the reduced zone occurs in the form of its own minerals, such as: native silver, stromeyerite, mckinstryite, jalpaite, naumannite, silver amalgams. Futhermore, silver is present asCu and Fe isomorphic substitutions in the crystal lattice of copper sulfides of the Cu-S and Cu-Fe-S groups and in As and Sb sulfosalt. In the oxidized zone, silver occurs as electrum, silver amalgams and substitutions in remnant copper sulfides. A decrease in the concentration of silver in ore minerals and in the content of silver minerals towards the top of the mineralized interval is characteristic. The concentration of silver (both in the form of its own minerals and as isomorphic substitutions in ores) is impoverished in the zone where the oxidation front crosses the Kupferschiefer shale than in the case when the stabilization of the redox front is at the border boundary of the Weissliegend sandstone with and the Kupferschiefer shale. The spatial distribution of silver in the Lower Zechstein formations at the contact zone between the reduced and oxidized rocks is the result of the evolution of ore mineralization, caused by the flows of mineralizing solutions, as evidenced by the depletion of the oxidized zone in silver, and its enrichment in the adjacent reduced rocks.
A b s t r a c t. The characteristics of spatial distribution of silver minerals and Ag in ore minerals within the Lower Zechstein formations at the contact zone between reduced rocks and the Rote Fäule oxidized rocks are shown. All presented outcomes are on based on rock material taken from mining profiles and some archival boreholes in the Radwanice-Gaworzyce deposit area. These studies were used microscopic observations in reflected light and by microprobe analyses using the CAMECASX-100. In all analyzed profiles, oxidized rocks (enriched in hematite) were found, which occur at various levels of the Kupferschiefer series beneath the reduced zone enriched in ore minerals. Silver in the reduced zone occurs in the form of its own minerals, such as: native silver, stromeyerite, mckinstryite, jalpaite, naumannite, silver amalgams. Futhermore, silver is present asCu and Fe isomorphic substitutions in the crystal lattice of copper sulfides of the Cu-S and Cu-Fe-S groups and in As and Sb sulfosalt. In the oxidized zone, silver occurs as electrum, silver amalgams and substitutions in remnant copper sulfides. A decrease in the concentration of silver in ore minerals and in the content of silver minerals towards the top of the mineralized interval is characteristic. The concentration of silver (both in the form of its own minerals and as isomorphic substitutions in ores) is impoverished in the zone where the oxidation front crosses the Kupferschiefer shale than in the case when the stabilization of the redox front is at the border boundary of the Weissliegend sandstone with and the Kupferschiefer shale. The spatial distribution of silver in the Lower Zechstein formations at the contact zone between the reduced and oxidized rocks is the result of the evolution of ore mineralization, caused by the flows of mineralizing solutions, as evidenced by the depletion of the oxidized zone in silver, and its enrichment in the adjacent reduced rocks.