Nowsze badania nad dolomitami kruszconośnymi

Abstract

NEW STUDIES ON THE ORE-BEARING DOLOMITES Summary The zinc-lead ore minerals of the Silesia-Cracow area are bound up with the dolomites thought to be the ore-bearing ones. This is a cause of needs of study on distribution and properties of these dolomites. Studies are possible owing to the numerous drillings connected with the search for zinc-lead deposits. Approximately 200 samples were examined and dolomiticity coefficient as a relation of magnesium oxide content to that of calcium oxide was determined. Microscopic studies, spectral analyses and roentgenospectral investigations were also made. On this basis both the petrographical and the geochemical differences of the ore-bearing dolomites have been established in relation to the other Triassic dolomite sediments and the considerable irregularity of their extent depending on tectonics has been determined, too. Taking that into consideration, as well as the suggestions resulting of the palaentological data, one can draw conclusions concerning epigenetic character of the ore-bearing dolomites. Much data show that these sediments originated as a result of dolomitization caused by the descension solutions still before Jurassic.