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چکیده
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The Kuh e-Dom intrusion is part of Urumieh- Dokhtar magmatism in the central Iran tectonic zone. These rocks range from acidic rocks (SiO2=62.68– 67.3 wt.%; Mg# =32.2–46.04) including granodiorite, monzogranite, quartz monzonite and quartz-monzodiorite composition to basic-intermediate rocks (SiO2=48.5– 57.3 wt.%; Mg#=38.87– 57.06) including gabbro, diorite, quartz diorite, monzodiorite and monzonite composition. The major and trace elements of the intrusion rocks along with Sr– Nd isotopic data of the granitoid rocks gathered from the Kuh- e Dom intrusion were studied to understand the underlying petrogenesis. Mineralogical evidence supports its characteristics as I-type because it has pyroxene, amphibole, biotite, magnetite and euhedral titanite, and lacks muscovite and other primary aluminous silicates such as garnet, cordierite, and sillimanite. This is also supported by its association with volcanic rocks and absence of high temperature metamorphic rocks. Furthermore, these rocks show a marked reduction in P2O5 when SiO2 contents are increased (Not shown). This feature is an important criterion for distinguishing I-type granites from S-type granites because apatite reaches saturation in metaluminous and mildly peraluminous magmas (A/CNK<1.1) but is highly soluble in strongly peraluminous melts [12]. Hence, these rocks could be outlined; the emplacement of the plutons, which are I-type and metaluminous characteristics and mostly belong to the high-K calc-alkaline series, took place at 47 Ma. They are enriched in LILE and LREE relative to the HFSE and HREE with negative Ba, Nb, Ti, Ta, P, Sr and Eu anomalies in the most samples so, the acidic rocks present strongly pronounced negative anomalies in Ba (Ba/Ba* = 0.250.5), Nb (Nb/Nb* = 0.19- 0.43), Sr (Sr/Sr* = 0.34-0.85), P (P/P* = 0.1-0.53) , Ti (Ti/ Ti*= 0.13-0.23), Ta (Ta/Ta* = 0.290.65), and Eu (Eu/Eu*: 0.58- 0.88) and Basic-intermediate rocks exhibit negative anomalies in Ba, Nb, Ti and to a lesser extent Ta (
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