DIAPIRISM, MAGMATISM AND MINERALIZATION IN THE HORMOZ ISLAND, PERSIAN GULF, SOUTH IRAN

Hormoz island is situated within the Persian Gulf in southern Iran. It is a salt-gypsum diapir that comprises diverse rock types ranging in age from pre-Cambrian to recent. It is part of a group of diapirs in Iran that are present in older (500-800 Ma) rocks known as the south Zagros group, (including Hormoz). This contrasts with the younger (or Great Kavir group) of diapirs in exclusively Tertiary rocks. Combined, the diapirs in Central Iran (Great Kavir) and south of Zagros form a prominent province on a global scale with over 500 occurrences known or suspected. The Hormoz diapir is unusual in many respects because of its recent tectonic activity, and unusual low- and high-temperature mineralization that formed deposits of gypsum, anhydrite, calcite, dolomite, hematite, hydro-hematite, goethite, pyrite, kaolinite, halite, as well as augite, hornblende, ilmenite, apatite, and feldspar. The role of magmatism (presently undated) in the context of diapirism remains yet to be resolved.