Hydrothermal fluid evolution in collisional Miocene porphyry copper deposits in Iran: Insights into factors controlling metal fertility

Publikationen: Beitrag in FachzeitschriftArtikelForschung(peer-reviewed)

Autoren

Externe Organisationseinheiten

  • Shahid Chamran University of Ahvaz
  • Shiraz University
  • University of New Brunswick

Abstract

The Cenozoic Urumieh-Dokhtar Magmatic Belt (UDMB) in Iran is considered as one of the major Cu-bearing regions in the world with high potential for the occurrence of giant/large porphyry Cu ± Mo ± Au systems. In the UDMB, porphyry Cu mineralization is strictly associated with Miocene intrusions originating mostly from collisional-related partial melting of subduction-modified juvenile lower crust. In this study fluid inclusion coupled with laser Raman analysis is used to characterize and compare the fluid evolution of the large Meiduk deposit and smaller low grade porphyry copper systems (e.g., Keder, Sarkuh, and Iju) in the UDMB. It can be shown that enhancement of metal fertility of a porphyry system is controlled by several factors: (1) The salinity of early hydrothermal ore fluids; maximum ore-efficiency is seen in porphyry deposits showing supersaturation of NaCl in the pristine high temperature fluids (e.g., Meiduk), (2) Presence of CO 2 and fast exhausting of CO 2 vapor components during early stages of mineralization, (3) Temperature decrease especially during the main ore stage, and (4) High oxygen fugacity (near to the magnetite – hematite oxygen buffer) of the most primitive fluids in the early stages of hydrothermal system.

Details

OriginalspracheEnglisch
Seiten (von - bis)183-200
Seitenumfang18
FachzeitschriftOre geology reviews
Jahrgang105.2019
AusgabenummerFebruary
Frühes Online-Datum31 Dez 2018
DOIs
StatusVeröffentlicht - 1 Feb 2019