Sediment-hosted disseminated gold mineralisation at Zarshuran, NW Iran

Mineralogy, geochemistry and geodynamic setting of the granitoids from NW Iran

“…The metamorphic rocks have been thrust over Oligocene to Miocene volcano-sedimentary rocks along the NW-SE Qeynarj-e-Chartagh thrust fault (Figure 2), but they are overlained unconformably by Tertiary rocks in the east of the area (Babakhani and Ghalamghash, 1990). K-Ar dating of carbonaceous schists in the Zarshuran area (Mehrabi et al, 1999), apatite U-Th/He data from the Mahneshan area (Stockli et al, 2004), and 40 Ar-39 Ar dating of muscovite schists (Gilg et al, 2006), constrains the timing of rapid exhumation of the basement rocks to the Early Miocene (20 Ma). The U-Pb zircon intrusion age of the granitic gneisses in the Mahneshan metamorphic complex $560 Ma (Stockli et al, 2004) is similar to U-Pb dates from basement rocks of the Saghand area from the Central Iran Zone (Ramezani and Tucker, 2003).…”

Petrogenesis and Tectono-Magmatic Setting of Meso-Cenozoic Magmatism in Azerbaijan Province, Northwestern Iran

“…Recent studies indicate the probable existence of porphyry type mineralization in the Hashtrud-Mianeh region accompanying Oligocene plutonism that intruded the Eocene volcanic rocks (Jamali, 2011;unpublished data). Miocene magmatism with an adakitic signature and mildly alkaline affinity is accompanied with epithermal and Carlin type gold mineralization in Ghorveh and Takab regions (Mehrabi et al, 1999;Richards, 2006 and2009).…”

Arsenic in Natural Environments

“…In some cases, stable isotope analyses, outcrop characteristics, radiometric dating, and mineral overgrowths may be used to decipher the origins and age relationships between minerals (e.g. Faure and Brathwaite, 2006;Mehrabi, Yardley and Cann, 1999;Zachariás et al, 2004;Sidle, Wotten and Murphy, 2001;Sidle, 2002;. Specifically, the Getchell hydrothermal gold deposits in north-central Nevada, USA, contain arsenopyrite, arsenian pyrite, orpiment, and realgar Cline, 2001).…”

“…Natural stibnite may contain more than 0.5 wt% of arsenic (Ashley et al, 2003). Other arsenic-bearing minerals that may be present in hydrothermal deposits include: orpiment, realgar, nickeline (NiAs), loellingite (FeAs 2 ), tennantite ((Cu,Fe) 12 As 4 S 13 ), and arsenolite (As 2 O 3 ) (Pfeifer et al, 2004, 207;Craig, Vaughan and Skinner, 2001, 353;Mandal and Suzuki, 2002;Van Moort, Hotchkis and Pwa, 1995;Mehrabi, Yardley and Cann, 1999).…”