Metallogenesis of the sediment-hosted stratiform Cu deposits of the Ravar Copper Belt (RCB), Central Iran

- The Ravar copper belt (RCB) was introduced for first time.
- The RCB is a Cu-Ag-U red bed type sediment-hosted stratiform copper (SSC) belt.
- Spionkopite as a common supergene mineral in the SSC deposits, is recognized in this belt.
- Marcasite that was less reported in SSC deposits of the world, is a common mineral in the RCB.

The Ravar Copper Belt (RCB) is located in the north of Kerman in the Central Iran. This belt is a part of the Tabas Block which is 450 km long and 50 km wide. It is bounded by Kuhbanan- Kalmard Fault in the west and Nayband Fault in the east. The main lithological units in the RCB are Mesozoic sedimentary rocks. The stratigraphic sequence includes evaporites, continental red beds and limestone, similar to other sedimentary Cu belts around the world. Sandstone is the most common host rock in the RCB and has arenite composition which was formed in fluvial to deltaic environment related to foreland basin. Mineralization is closely related to plant fossils and the main ore minerals include chalcocite, bornite, pyrite, marcasite, argentite, spionkopite, covellite, malachite, etc. Replacement, dissemination, banding and veinlet are the most common ore textures which suggest an epigenetic origin related to the early diagenetic stage. Geochemical signatures indicate that RCB is a Cu-Ag-U Red bed type sediment-hosted copper belt similar to Paradox basin and Central Andes deposits. In addition to Cu (3%), minor amounts of Ag, U, Hg, Pb and Au are also existed. Negative values of δ34S show that sulfur is introduced by BRS process and is more derived from organic maters destruction. It is proposed that meteoric and ground waters achieved high salinity while passing through the lower evaporite sequences, thus being able to leach metals from thick red beds as chloride complexes during upward flows. Ore deposition occurred when the metal bearing solution reached to the organic rich gray bed.