Mineralizacja endogeniczna w masywach skał ultrazasadowych północnego przedpola Sudetów Środkowych

Abstract

ENDOGENOUS MINERALIZATION OF ULTRABASIC ROCK MASSIFS IN THE NORTHERN FOREFIELD OF MIDDLE SUDETES Summary Small vein intrusions found to occur in serpentinites of the Gogołów-Jordanów massif, Lower Silesia, are described. Dykes of strongly hydrolized microgabbro, lamprophyres of the groups of camptospessartite and vogesite, grey and white aplites, as well as gabbroic and granitic pegmatites are distinguished, and their character and occurrence conditions are given. The vein intrusions reveal contact selvage of reaction rim type, with well developed hydrobiotite, vermiculite, talcous arid chlorite zones. The chemical compositions of the vein intrusions are presented in the projection according to S.R.N. Nocholds and R. Allen. Distinguished are two magmatic differentiation series, one with the main gabbro intrusion of Sobótka, another with the Sobótka granite, two series of differentiation of fractional gabbroic and granite magma. The differentiation of rocks in small vein intrusions has been explained by assimilation of ultrabasic rocks, according to the differentiation of serpentinite massifs, as regards magnesium and calcium contents. Hydrothermal magnesite mineralization related to post-magmatic activity of granite intrusion has been characterized genetically, as well.