Acta Montanistica Slovaca (Dec 2002)
The influence of tectonical structures on the stability rock massif in the area of the magnesite deposit Jelava of the Dúbrava massif
Abstract
Magnesite deposits Dúbrava and Miková are located in Carboniferous formations between Brádno and Ochtiná (Dúbrava massif). Carboniferous magnesites are, according to the lithostratigraphic division of Early Paleozoic complexes of Gemericum by Bajaník et al. (1983), situated in the Dobiná Group, more precisely in the upper part of the Ochtiná Formation, in the environment of black schists with intercalation of metabasalts and their pyroclastics. In the lower parts of the formation are small-pebble conglomerates and polymict sandstones. Carbonatic bodies of the Dúbrava massif has the directional length, 4 500 m, course NE-SW, inclination 55-60o to SE and maximal thickness 600 m. A calculation in 1967 indicated above 500 millions kt of reserves whish after a modification of conditional parameters was reduced to its three fifths. Reserves excluded during the second calculation had a higher content of Fe2O3 causing the lowering of fireproof products quality.In the text the structural and stability conditions in the area of the Dúbrava deposit and the Miková deposit of the Dúbrava massif are analysed.