Geoquímica de isótopos estáveis (C, S e O) das rochas encaisantes e do minério de Cu(Au) do depósito cristalino, província mineral de Carajás, Pará

Abstract

We describe stable isotopic data from country rocks and sulfide ores of the Cristalino Cu(Au) deposit (CD), Carajás Province, Brazil. Calcite from whole rock and sulfides grains from mafic to felsic volcanics and “hydrothermal breccias” were analyzed. The CD, an Archean (ca. 2.7Ga) IOCG deposit, occurs in hydrothermalized (e.g., alkalinization; carbonatization; sulfidation; etc.) Itacaiúnas Supergroup supracrustals. Diorites crosscut these rocks and can relate to Cu-ore. Isotopic signatures of ä34S and ä13C and ä18O plot in the mantle sulfides and in the carbonatite primary field respectively. Ore fluids may be derived from a granitic or dioritic intrusion or leached from MORB-type mafic volcanic rocks