Acta Montanistica Slovaca (Dec 1998)
The characteristics of the Rožňava ore district, in relation to the structural-tectonic analysis and mineralization exampled by the deposition conditions
Abstract
The argentiferrous quartz-siderite-sulphide Strieborná vein hosted by mid-greenschist facies of Lower Paleozoic sequences represents one of the important vein structures of epigenetic mineralisation within the Rožňava ore district, Slovakia. The lenticular vein consists of some ore columns with high-grade fine to medium-grained semimassive and massive sulphides with Ag-tetrahedrite as the principal mineral of the sulphide stage. The mesoscopic analysis demonstrates that the sulphide mineralisation and enclosing rocks were subjected to successive stages of penetrative deformation and recrystallisation within the brittle-ductile shear zone. It is concluded that relatively later brittle-ductile deformations of sulphides are most evident within and along reactived subvertical fault zones to which the highest accumulation of sulphides is restricted. A wide variety of brittleductile deformation textures has been identified. Brittle and ductile deformation textures such as intense cataclasis, grain indentation, grain boundary migration, dislocations, plasticity reflect the response of the sulphides to various degrees of deformation, recrystallisation and remobilisation. The distribution of deformation textures within orebodies with a highgrade sulphide ore (Ag-tetrahedrite) suggests a strong strain partitioning along reactived fault zones. It is postulated that a later focussed fluid flow in these zones had significant effects on the strain of earlier sulphides and emplacement of high ore concentrations.
