عنوان مقاله [English]
The Miduk porphyry copper deposit is located in central-southern Iran. Mineralization is emplaced in Eocene volcanic rocks of andesite-basalt composition. Copper mineralization is accompanied by both potassic and phyllic alteration. The main mineralization is in the potassic alteration zone. In this paper, four alteration stages (potassic, transition, phyllic, and propylitic) have been studied, in terms of mass transfer and element mobility, during the hydrothermal process. In order to illustrate these changes quantitatively, isocon plots have been used. Isocon plots indicate that Si, Ti, Al, Ga are relatively immobile during alteration. In all stages of hydrothermal alteration, volume changes are close to zero. In the potassic alteration zone, there is an obvious enrichment of K, Ba and a depletion of Na, Ca, Mg and Mn. In the transition alteration zone, Ca is added, Cu and K are depleted and Na and Mg are relatively unchanged. In the phyllic alteration zone, Na, K and Ba are depleted and Cu, Ca and Fe were enriched. Finally, in the propylitic alteration zone, Fe and Ba are depleted and Ca, Mg, Na and Cu are enriched.