scholarly journals Mineral chemistry and formation conditions of calc-silicate minerals of Qozlou Fe skarn deposit, Zanjan Province, NW Iran

2019 ◽  
Vol 12 (21) ◽  
Author(s):  
Mir Ali Asghar Mokhtari ◽  
Hossein Kouhestani ◽  
Kazem Gholizadeh
Keyword(s):  
Mineral Chemistry ◽  
Skarn Deposit ◽  
Silicate Minerals ◽  
Porphyritic Granite ◽  
Nw Iran ◽  
High K ◽  
Ore Minerals ◽  
Mineralized Zone ◽  
Supergene Processes ◽  
Carbonaceous Rocks

Abstract The Qozlou Fe skarn deposit is located at the Abhar–Mahneshan belt of the Central Iranian Zone. It is associated with Upper Eocene porphyritic granite that intruded into the Upper Cretaceous impure carbonaceous rocks. The Qozlou granite has high-K calc-alkaline affinity and is classified as subduction-related metaluminous I-type granitoids. Skarn aureole in the Qozlou is composed of endoskarn and exoskarn zones, with the exoskarn zone being the main skarn and mineralized zone. It includes garnet skarn, garnet-pyroxene skarn, pyroxene skarn, epidote skarn, and pyroxene-bearing marble sub-zones. The Qozlou Fe deposit is 300 m long and 5–30 m wide. Magnetite is the main ore mineral associated to pyrite, chalcopyrite, and pyrrhotite. Garnet, clinopyroxene, actinolite, epidote, calcite, and quartz occur as gangue minerals. Covellite, hematite, and goethite were formed during the supergene processes. The ore and gangue minerals have massive, banded, disseminated, brecciated, vein–veinlets, replacement, and relict textures. EPMA data indicate that garnets have andradite–grossularite compositions (Ad39.97–100–Gr0–49.62) and clinopyroxenes have diopsidic composition (En29.43–42.5–Fs14.31–20.99–Wo43.08–50.17). Based on mineralogical and textural criteria, skarnification processes in the Qozlou skarn can be categorized into three discrete stages: (1) isochemical (metamorphic–bimetasomatic), (2) metasomatic prograde, and (3) metasomatic retrograde. Anhydrous calc-silicate minerals (garnet and clinopyroxene) were formed during the prograde metasomatic stage, while ore minerals and hydrous calc-silicate minerals were formed during the retrograde ore-forming sub-stage. Temperature and ƒO2 conditions range between 430 and 550 °C and 10−26 and 10−23, respectively, for the metasomatic prograde stage. The retrograde metasomatizing fluids had likely ƒS2 = 10−6.5 and temperatures < 430 °C at the beginning of the ore-forming sub-stage.

Geology, mineral chemistry and formation conditions of calc-silicate minerals of Astamal Fe-LREE distal skarn deposit, Eastern Azarbaijan Province, NW Iran

2015 ◽  
Vol 68 ◽  
pp. 79-96 ◽  
Author(s):  
Saeid Baghban ◽  
Mohammad Reza Hosseinzadeh ◽  
Mohsen Moayyed ◽  
Mir Ali Asghar Mokhtari ◽  
Daniel Gregory
Keyword(s):  
Mineral Chemistry ◽  
Skarn Deposit ◽  
Silicate Minerals ◽  
Nw Iran ◽  
Formation Conditions

scholarly journals Petrology and mineral chemistry of peraluminous Marziyan granites, Sanandaj-Sirjan metamorphic belt (NW Iran)

2015 ◽  
Vol 66 (5) ◽  
pp. 361-374 ◽  
Author(s):  
Esmaiel Darvishi ◽  
Mahmoud Khalili ◽  
Roy Beavers ◽  
Mohammad Sayari
Keyword(s):  
Mineral Chemistry ◽  
White Mica ◽  
Granitic Rocks ◽  
Calc Alkaline ◽  
Metamorphic Belt ◽  
Nw Iran ◽  
The North ◽  
Continental Plate ◽  
High K ◽  
Type Granite

AbstractThe Marziyan granites are located in the north of Azna and crop out in the Sanandaj-Sirjan metamorphic belt. These rocks contain minerals such as quartz, K-feldspars, plagioclase, biotite, muscovite, garnet, tourmaline and minor sillimanite. The mineral chemistry of biotite indicates Fe-rich (siderophyllite), low TiO2, high Al2O3, and low MgO nature, suggesting considerable Al concentration in the source magma. These biotites crystallized from peraluminous S-type granite magma belonging to the ilmenite series. The white mica is rich in alumina and has muscovite composition. The peraluminous nature of these rocks is manifested by their remarkably high SiO2, Al2O3and high molar A/CNK (> 1.1) ratio. The latter feature is reflected by the presence of garnet and muscovite. All field observations, petrography, mineral chemistry and petrology evidence indicate a peraluminous, S-type nature of the Marziyan granitic rocks that formed by partial melting of metapelite rocks in the mid to upper crust possibly under vapour-absent conditions. These rocks display geochemical characteristics that span the medium to high-K and calc-alkaline nature and profound chemical features typical of syn-collisional magmatism during collision of the Afro-Arabian continental plate and the Central Iranian microplate.

scholarly journals Rare and Critical Metals in Pyrite, Chalcopyrite, Magnetite, and Titanite from the Vathi Porphyry Cu-Au±Mo Deposit, Northern Greece

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 630
Author(s):  
Christos L. Stergiou ◽  
Vasilios Melfos ◽  
Panagiotis Voudouris ◽  
Lambrini Papadopoulou ◽  
Paul G. Spry ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Mineral Chemistry ◽  
Critical Metals ◽  
Northern Greece ◽  
Inductively Coupled ◽  
Porphyry Cu ◽  
Icp Ms ◽  
Quartz Monzonite ◽  
Ore Minerals ◽  
Plasma Mass Spectrometry

The Vathi porphyry Cu-Au±Mo deposit is located in the Kilkis ore district, northern Greece. Hydrothermally altered and mineralized samples of latite and quartz monzonite are enriched with numerous rare and critical metals. The present study focuses on the bulk geochemistry and the mineral chemistry of pyrite, chalcopyrite, magnetite, and titanite. Pyrite and chalcopyrite are the most abundant ore minerals at Vathi and are related to potassic, propylitic, and sericitic hydrothermal alterations (A- and D-veins), as well as to the late-stage epithermal overprint (E-veins). Magnetite and titanite are found mainly in M-type veins and as disseminations in the potassic-calcic alteration of quartz monzonite. Disseminated magnetite is also present in the potassic alteration in latite, which is overprinted by sericitic alteration. Scanning electron microscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of pyrite and chalcopyrite reveal the presence of pyrrhotite, galena, and Bi-telluride inclusions in pyrite and enrichments of Ag, Co, Sb, Se, and Ti. Chalcopyrite hosts bornite, sphalerite, galena, and Bi-sulfosalt inclusions and is enriched with Ag, In, and Ti. Inclusions of wittichenite, tetradymite, and cuprobismutite reflect enrichments of Te and Bi in the mineralizing fluids. Native gold is related to A- and D-type veins and is found as nano-inclusions in pyrite. Titanite inclusions characterize magnetite, whereas titanite is a major host of Ce, Gd, La, Nd, Sm, Th, and W.

scholarly journals Mineral chemistry of magnetite and fluid inclusions studies in the Kuh-Baba iron deposit, south of Hashtroud, NW Iran

2019 ◽  
Vol 27 (4) ◽  
pp. 755-766
Author(s):  
Majid Hafez Darbani ◽  
◽  
Ali Abedini ◽  
Farhang Aliyari ◽  
AliAsghar Calagari ◽  
...  
Keyword(s):  
Fluid Inclusions ◽  
Mineral Chemistry ◽  
Iron Deposit ◽  
Nw Iran

scholarly journals Lineament Patterns and Mineralization Related to Alteration Zone by Using ASAR-ASTER Imagery in Hize Jan-Sharaf Abad Au-Ag Epithermal Mineralized Zone (East Azarbaijan—NW Iran)

2016 ◽  
Vol 06 (04) ◽  
pp. 232-250 ◽  
Author(s):  
Shabnam Khosroshahizadeh ◽  
Mohsen Pourkermani ◽  
Mahmood Almasian ◽  
Mehran Arian ◽  
Ahmad Khakzad
Keyword(s):  
Alteration Zone ◽  
Nw Iran ◽  
Mineralized Zone

scholarly journals Petrogenesis of the post-collisional porphyritic granitoids from Jhalida, Chhotanagpur Gneissic Complex, eastern India

2020 ◽  
pp. 1-37
Author(s):  
Poulami Roy ◽  
Bapi Goswami ◽  
Sukanya Dutta ◽  
Chittaranjan Bhattacharyya
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
High Alumina ◽  
Strong Negative Correlation ◽  
Porphyritic Granite ◽  
High K ◽  
Granitoid Magma ◽  
Heavy Rare Earth Elements ◽  
Set Up ◽  
Batch Melting

Abstract The Jhalida porphyritic granitoid pluton is exposed in a regional shear zone belonging to the Chhotanagpur Gneissic Complex of the Satpura Orogen (c. 1.0 Ga), regarded as the collisional suture between the South and North Indian blocks. The pluton intruded the migmatitic gneisses, metapelites, calc-silicate rocks and amphibolites belonging to the amphibolite facies. The mineral assemblage indicates the calc-alkaline nature of the granitoids. Mafic (Pl–Qz–Bt±Hbl) schists occur as xenoliths within the pluton. The granitoids are classified as alkali-calcic to alkalic, dominantly magnesian grading to ferroan, metaluminous to slightly peraluminous, and shoshonitic to ultrapotassic. Geochemically, the granitoids are enriched in large-ion lithophile elements (LILE), particularly K, and light rare earth elements (LREE), but are comparatively depleted in Nb, Ta, and heavy rare earth elements (HREE). The strong negative correlation between SiO2 and P2O5, metaluminous to weakly peraluminous character, high liquidus temperature (798–891°C) and high fO2 (ΔQFM +0.8 to +1.6) of the melt suggest their I-type nature. Field relations and tectonic discrimination diagrams imply their post-collisional emplacement. Low Nb/U (average 8.5), Ce/Pb (average 9.0), and Al2O3/(Al2O3 + FeO(t) + MgO + TiO2) ratios and relatively low Mg number (average 0.15) of these granitoids indicate a crustal mafic source. Batch melting (at 825–950°C) of 10–20% of an old, incompatible elements-rich high-K high-alumina hornblende granulite can generate the porphyritic granite melt. The heat source for melting was an upwelling of the asthenospheric mantle in the post-collisional set-up. Textural and chemical characteristics of the mafic xenoliths show that invading porphyritic granitoid magma metasomatized the amphibolite protoliths.

scholarly journals Geochronological and Geochemical Constraints on the Origin of the Hutouya Polymetallic Skarn Deposit in the East Kunlun Orogenic Belt, NW China

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1136
Author(s):  
Hongchang Gao ◽  
Fengyue Sun ◽  
Bile Li ◽  
Ye Qian ◽  
Li Wang ◽  
...  
Keyword(s):  
Lower Crust ◽  
Inductively Coupled Plasma ◽  
Orogenic Belt ◽  
Granitic Rocks ◽  
Skarn Deposit ◽  
Nw China ◽  
Inductively Coupled ◽  
East Kunlun ◽  
Ore Minerals ◽  
East Kunlun Orogenic Belt

The Hutouya polymetallic skarn deposit lies in the Qimantagh area of the East Kunlun Orogenic Belt, NW China. Skarnization and mineralization at the deposit are closely associated with contemporary felsic intrusions. In this paper, zircon U-Pb ages and zircon Hf isotope as well as whole-rock geochemical and whole-rock Sr-Nd isotope data are reported for intrusive rocks and crystal tuff of the Elashan Formation in the Hutouya area. Moreover, Re-Os ages and S-Pb isotopes are also reported for the ore minerals in the Hutouya deposit. The Zircon laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) U-Pb age of granodiorite and Re-Os isochron age of molybdenite suggest that mineralizations occurred at ca. 227 Ma and that the granodiorite and molybdenite are closely related petrogenetically. All the granitoids in the Hutouya deposit are high-K calc-alkaline and metaluminous to weakly peraluminous I-type granitoids. Among them, the ore-forming granitoids were derived by the mixing of crust-derived (either juvenile or ancient mature lower crust) and mantle-derived magmas, whereas the non-ore-related granite porphyry was generated by the partial melting of a single ancient mature lower crust. The magmas of all the granitoids underwent extensive fractionation–crystallization during the process of rising and emplacement. The sulfur of the analyzed samples from the northern and middle zone of Hutouya deposit (including No. II, III, IV, and VI ore belts) belongs to deep magmatic sulfur, while the sulfur of samples from the southern zone of Hutouya deposit (No. VII ore belt) includes not only deep magmatic sulfur but also a contribution of strata sulfur. All the ore mineral samples in the Hutouya deposit have similar Pb compositions that are consistently derived from a mixed source of upper crust and mantle. Tectonic discrimination diagrams indicate a post-collisional setting for all granitic rocks of the Hutouya skarn deposit, which is therefore considered a product of a the post-collision extensional system and is consistent with other porphyry-skarn deposits within the East Kunlun Orogenic Belt.

scholarly journals Geochronological and geochemical constraints on the petrogenesis of high-K granite from the Suffi abad area, Sanandaj-Sirjan Zone, NW Iran

Geochemistry ◽  
2011 ◽  
Vol 71 (4) ◽  
pp. 363-376 ◽  
Author(s):  
Hossein Azizi ◽  
Yoshihiro Asahara ◽  
Behzad Mehrabi ◽  
Sun Lin Chung
Keyword(s):  
Nw Iran ◽  
High K ◽  
Sanandaj Sirjan Zone ◽  
Geochemical Constraints

scholarly journals STRUCTURAL AND MORPHOLOGICAL FEATURES OF VERBA MOLYBDENUM ORE MINERALIZATION

2018 ◽  
pp. 15-19
Author(s):  
M. M. Kostenko ◽  
P. A. Kondratenko
Keyword(s):  
Internal Structure ◽  
Complex Structure ◽  
Morphological Features ◽  
Ukrainian Shield ◽  
Granite Massif ◽  
South Eastern ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Mineralized Zone ◽  
Native Bismuth

The article shows the Verba ore mineralization of molybdenum (Volyn Block of the Ukrainian Shield) is associated with small granite intrusions. They are located in the south-eastern exocontact zone of the Ustynivka granite massif of the Paleoproterozoic Chisinau complex. The Verba minera­lization is a linear-coarse mineralized zone of the complex structure. This is confirmed by the development in its rocks of frequent, non-orientated veins of quartz, fluorite-quartz and carbonate-quartz compositions and numerous cracks. They have molybdenite and concomitant mineralization, as well as the wide spreading of molybdenite inclusions directly in the granites. A number of differently oriented faults and of small fracturing local zones, cataclasite, millonitized and breccias represents the internal structure of the mineralized zone. The characteristic of molybdenite the leading ore minerals is shown. It is morphologically represented by a closely connected scattered inclusions, rarely veined inclusions, and associated ore minerals: cassiterite, bismuth, native bismuth, emlectocytes, galena, sphalerite, chalcopyrite, pyrite, ilmenite, magnetite and titanomagnetite.

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