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Basic rocks appear as cumulative hornblende gabbros in the Namen pluton, West of Sabzevar. One outcrop of these rocks contains magnetite ore patches. Although magnetite- bearing hornblende gabbro (MHG) and other hornblende gabbros (HG) have similar mineralogy, their trace element compositions are completely different. Trace element analysis of magnetite minerals by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method on the MHG, HG and ore (MG) indicate that all magnetites could be classified as Ti and V enriched magmatic magnetite. MG and MHG magnetites have similar composition but trace element composition of HG magnetites display distinct characteristics. The HG magnetites are enriched in Mg, Al, Ga, Y, Nb and REE; while the MG and MHG have relatively higher concentration of Ti, V, Cr, Mn and Zn. These two groups show different trends in the REE diagrams. The MG and MHG magnetites have tetrahedral REE pattern with depleted LREE [(La/Yb)_N= 0.46]; while HG magnetites illustrate relative enrichment of LREE/HREE [(La/Yb)_N= 2.67]. The incorporation of magnetite trace elements and whole rocks geochemical data confirm the role of volatile phase separation in the gabbroic magma evolution in the Namen pluton.

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The study area is located in Tertiary plutonic belt of Lut Block.  Tertiary intrusive injection in Cretaceous limestone caused the formation of skarn in this region. Injection intrusive changes the texture and mineralogy of limestone and skarn or marble formed. A lens-shaped iron mineralization mainly occurred in the border of intrusions and calcareous unit. Petrological studies show that the whole combination intrusive quartz-monzonite, quartz monzonite to granodiorite variables. These granitoids are sub-alkaline series and they are meta-aluminous. Geochemical features show that they belong to I-type granitoids. Enrichment in Light rare earth elements (LREE) rather than HREE and a slight negative anomaly of Eu are important evidence that show the intrusions were formed in a magmatic belt on subductions zone and belong to calc-alkaline volcanic arc setting in active continental margins. Different geochemical graphs show consistency granitoid intrusions in south of Moein Abad with iron skarn-related intrusions

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The chromitite ores of Sabzevar ophiolitic zone could be divided into two groups of high Cr and high Al. The concentration of Cr₂O₃, As, S and some heavy metals (Cu, Ni, Ag, Co, Zn) is higher in high Cr samples; while high Al chromitites show higher concentration of Al₂O₃, SiO₂, TiO₂ and other trace elements. The high Cr chromitites have higher PGE than Al-rich samples and PGE concentration increases with Cr₂O₃. The high Cr chromitites have fractionated PGE chondrite- normalized patterns with negative slope (Pd/Ir = 0.25) and high IPGE/PPGE (average 6.22); while high Al chromitites show unfractionated and relatively flat patterns
(Pd/Ir = 1.9, IPGE/PPGE = 2.88). The PGE composition of high Cr chromitites indicates they are formed by high degrees of partial melting (boninitic melt) in arc setting. In contrast, Al- enriched samples have been produced by low degrees of partial melting (toleiitic melt) beneath spreading centers (i.e., mid-ocean ridges or back-arc basins). The results of PGE composition of Sabzevar chromitites are coincident with chemical composition data of chromite crystals in these samples.

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The clinopyroxene composition of two types of alkaline and calc-alkaline gabbros at Piranshahr pluton was investigated in this study. The major oxides variations are similar in all clinopyroxenes of two types of gabbros and are classified as diopside- augite; but trace element compositions are very different in these two groups. The clinopyroxenes of alkaline gabbros are rich in high field strength elements (HFSE) and rare earth elements (ΣREE= 34- 64 ppm) and have high ⁸⁷Sr/⁸⁶Sr ratios. In other side, the clinopyroxenes in calc-alkaline samples have high Sr, Rb and Ba and elevated ⁸⁷Sr/⁸⁶Sr; but are depleted in HFSE and rare earth elements (ΣREE= 9.4- 21.6 ppm). Calculation of equilibrated melts from trace elements composition of clinopyroxenes using partition coefficients between clinopyroxene and the basaltic melt show that they are formed by different sources which is consistent with whole-rock geochemical data of gabbros.

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The studied mining area is located in the northeast of the Lut block, within the Ahangaran mountain range. The rock units in the region generally include limestone and metamorphosed carbonate rocks that are penetrated by intrusive masses with the composition of diorite, monzodiorite, granodiorite and granite. Based on the structural control of the mineralization zone and the formation of metasomatism succession with the presence of low-temperature hydrous minerals such as chlorite and epidote along with magnetite, the iron mineralization of the area can be considered as a low-temperature skarn type. The mineral chemistry of magnetite and the amounts of Ca, Ti, Al, V, Cr, Ni and Mn are also similar to skarn deposits. Field studies indicate that another younger intrusive mass at depth is the origin of the iron mineralization of the ore zone. Based on analysis of components, calculated on the basis of REE, the ore solution with magmatic origin has moved upward along the faults and after mixing with atmospheric fluids, as a result, it has created a reaction with the carbonate rocks of the iron ore.