THE CALCULATION OF MASS TRANSFER AND ELEMENT MOBILITY IN SAR-CHESHMEH GRANODIORITE STOCK, KERMAN-IRAN

4th International Scientific Conference - SGEM2004, www.sgem.org, SGEM2004 Conference Proceedings/ ISBN: 954-918181-2, June 14-18, 2004, 47- 62pp

ABSTRACT

Sar-Cheshmeh porphyry copper deposit, as the biggest copper mine in Iran is
located in southwest of Kerman. This deposit is located in southern part of Orumieh –
Dokhtar metallogenic belt, which is also the most important copper belt in Iran. The
Sar-Cheshmeh granodioritic stock, called “Sar-Cheshmeh Porphyry” is intruded into
the Eocene andesitic rocks. This intrusion has caused potassic (first mineralization
episode) and phyllic alteration zones in lower levels due to ascending toward the
lower temperatures, mixed magmatic and meteoric waters. Therefore, the potassic
alteration zone is overprinted by a later phyllic alteration episode. In this paper, based
on the graphical method of isocon, mass changes and element mobility within the
granodiorite stock have been calculated. The results show that Nb, Zr, Ti and P were
relatively immobile during the hydrothermal alteration episodes and their mass
conserved alteration. In potassic alteration zone, granodiorite rocks show enrichment
of K, Si, S, and depletion of Fe, Mg and Na, Because of the substitution of plagioclase
and amphibole by K-feldspar and biotite respectively. Increasing the copper content is
due to chalcopyrite crystallization within this alteration episode. During the phyllic
alteration, Silica is increasing drastically. It is also an obvious reduction of Na, K, Mg
(due to sericitazation of alkali-feldspars and alteration of ferromagnesian minerals)
within this alteration zones. Decreasing the copper is also due to copper leaching and
subsequence enrichment in supergene alteration in higher the levels.

Key words : Mass Change, Granodiorite, Isocon, Sar-Cheshmeh