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Siah-Kamar hornfalses and skarns are located about 5Km east of Dehsalm and 85Km west of Nehbandan city, southeast of Birjand Province and east of Lut Block. This Skarn formed by injected Rigi granitoid (Eocene age) into limestone and sandstone (Upper Cratacious).  Rigi Mountain is mainly granodiorite in composition and contains plagioclase, quartz, hornbelend and biotite minerals. Geochemistry and tectonic studies show that this pluton is calc-alkaline and I-type granite. Pyroxene, quartz and plagioclase are main minerals in hornfelses. Investigation of mineralogy and geochemistry Siah-Kamar skarns and hornfalses have indicated that formed during metamorphism and metasomatic stages (prograde and retrograde). Hornfalses and marbles are formed during metamorphism stage and prograde metamorphism stage formed anhydrous calc- silicate minerals assemblages (wollastonite, grossular- andradite and diopside).  During retrograde metasomatism, these minerals have effected by alteration and replacement with hydrous calc- silicate minerals (epidote, chlorite and low termolite-actinolite). Finally during latestaye metasomatism, fine aggregates assemblage minerals such as  of chlorite, quartz and clayminerals are formed. Presence of wollastonite, magnetite and andradite minerals shows that this skarn is formed nearly 550^oC temperature and high oxygen fugacity (fO2=10-12-10-23). Siah- Kamar Skarn has calcic- skarn type.

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 Oxygen fugacity (fO₂) and zircon crystallization temperatures (Ti-in-zircon) of ore-bearing quartz monzonite intrusive rocks of ChahShaljami and Dehsalam Cu-Mo porphyry deposits were measured by using calculations of zircon trace element values and oxidation conditions of parental magma were investigated. The Ce⁴⁺/Ce³⁺ values for ChahShaljami and Dehsalam are in a range of 8 to 295 with an average of 125 and 3 to 171 with an average of 35, respectively, therefore they were not in the favorable range for porphyry mineralization. The estimated fO₂ values for ChahShaljami and Dehsalam are in the range of ∆FMQ -1.8 to MFMQ +0.6 with an average of ∆FMQ -0.6 and ∆FMQ -1.3 to ∆FMQ -0.4 with an average of ∆FMQ -0.8 which is at least ∆FMQ +1 less than the values of porphyry copper mineralization in the world.. Based on the zircon log fO₂ values of ore-bearing intrusive rock, the parental magma originated from partial melting of supra-subduction mantle peridotite zone within oceanic slab. Melting under unfavorable conditions (under magnetite-hematite (HM) buffer and in faylite-magnetite-quartz (FMQ) buffer condition, and lack of sufficient Cu and sulfur at the source), which is supported by evidences in deposit such as lack of magnetite-hematite intergrowths, was not ideal for porphyry Cu porphyry mineralization in the two regions. The results are supported also by previous whole-rock major and trace element geochemistry and Sr-Nd isotopic values.