2024-03-29T03:00:45+03:30 http://ijcm.ir/browse.php?mag_id=51&slc_lang=fa&sid=1
51-827 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 Application of geochemical data in recognizing origin of Soltanieh dolomite and determining temperature of dolomite formation, in North of Semnan Shahmirzad village is located on the southern parts of the Eastern Alborz Mountain Ranges. One of the sedimentary rock units that crops out in this area is Soltanieh Formation (Upper Precambrian Lower Cambrian). Thin section and oxygen isotope studies have been used in order to determine the petrological characteristics and the temperature of Soltanieh dolomites formation environment. Examination of the petrographic properties of the dolomite samples, along with geochemical data reveals that all of the dolomite samples are diagenetic (secondary) and were formed under reducing conditions in shallow to deep phreatic environment. The heaviest and lightest IRO values illustrate that temperature of early to late diagenetic dolomites range from 72 t to 113.5 t respectively. Dolomite Oxygen Isotope Soltanieh Fm. Shahmirzad. 2002 4 01 3 16 http://ijcm.ir/article-1-827-en.pdf
51-828 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 Mineralo - Geochemical investigation on Kohe-zar Gold mineralization area, Torbate-Heydarie Gold - Polymetal mineralization of Kohe-zar area is located alout 35 kilometers southwest of Torbat - Heydarieh in Khorasan province. Mineralization was oeeured in quartz - speeularite ± pyrite ± chacopyrite veins and vein lets. The main ore minerals are specularite, chalcopyrite, pyrite, avinite (Bi - bearing tetraedrite), acanthite, native bismuth (occurred intergrowth with barite), native gold, electrum, coveline - digenite and weathered minerals such as geothite, hydrogeothite, eu-fe oxides, malachite. Ore minetalization of Kohe - zar is related to low - sulfide, quartz - hematite type of hydrothemal ore deposists. On the basis of therrnobarogeochemical investigation on quartz, medium temperature fluid with low potential mineralization is responsible for mineralization in this area. Ore mineralization Gold Electron Microprobe fluid Inclusion. 2002 4 01 17 32 http://ijcm.ir/article-1-828-en.pdf
51-829 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 Mineralogical and Geochemical Evaluation of Clay Minerals of Zonuz Mine, in Marand According to REE & SEM Studies in Comparison with Esteghlal Mine, in Abadeh The Zonuz irregular lens shaped kaolin deposit located in Marand, Azarbaygan, is exploited as an openpit. Andesite, Trachyandesite and dacite igneous rocks are located in south, west and east parts of the deposit, respectively. The Ore was analysed by XRD, SEM and NAA. Assemblage of major minerals including Quartz, Kaolinite, Illite and Calcite, and minor minerals of Dolomite, Montmorillonite and Limonite are detected. Geochemical analysis show that La, Ce, Nd are present in minor amounts, and the high ratio of LREEIHREE indicates the enrichment of LREE which is probably the result of surface tension ofthese elements on clay particles. Geological and Geochemical evidence indicate that hydrothermal fluids played a major role in the formation of the Ore body, particulary along fault zones. A comparison is also made between autogentic Zonuz deposit with allogentic Esteghlal deposit. Zonuz deposit Hydrothermal Mineralogy Geochemistry Rare Earth Element. 2002 4 01 33 50 http://ijcm.ir/article-1-829-en.pdf
51-830 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 Textures and REE geochemistry in Gian copper occurrence The Upper Devonian - Lower Carboniferous Sourian complex, is composed of clastic - carbonates, volcanic, metamorphic rocks and quartz lenses hosts copper mineralization in Gian area of Fars province. This complex is metamorphosed to green schist facies. This metamorphism resulted In massIve to disseminated sulfide mineralization in the direction of schistosity and within quartz lenses. Low-grade green schist facies metamorphism is recognized with cataclastic flow and fracturing of pyrite crystals, infilling of fractures of pyrite with chalcopyrite, pressure shadow of chalcopyrite around pyrite, recrystalization and presence of triple junctions in pyrite. Distribution pattern of REE in schists of Gian copper shows a decreasing trend from La to Lu. The ratio of 2:LREE/LHREE is more than one and the ratio of LaN I YbN is less than 15. This indicates that schists are formed by the metamorphism of shales and the ratio of (LalLu),,> 1 indicates that the transfer of REE has been affected by surface adsorption. It may be concluded that this copper occurrence is the result of ore-bearing shale metamorphism. copper metamorphism REE 2002 4 01 51 65 http://ijcm.ir/article-1-830-en.pdf
51-831 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 CLASSIFICATION OF AMPHIBOLES FROM IRON ORE DEPOSITES, SANGAN AREA, KHAF oeeuring in the Sangan arca was fonned within two different rock groups· graitoids and skarns. Based on the new amphibole classification and nomenclature, the general fonnula of amphibols IS (AB2C,T,O"OH),. Amphibole of granitoids is a ferroedenite in which Si = 6.87 - 7.75, CaR> 1.5, (Na+K)A > 0.5 and Ti < 0.5. Skarn amphiboles are mostly developed within amphibole skarns and gamet-pyroxene skarns during retrograde stage of skarn evolution. High-temperature amphiboles are rich in Al while low-temperature amphiboles are poor in AI. Skarn amphiboles are classified in two groups: (a) hastingsite in which Si = 5.99 - 6.08, CaB> 1.5, (Na+K)A > 0.5, Ca < 0.5 and Al < Fe+] (b) ferroactinolite in which Si = 7.61 - 7.90, CaB>1.5, (Na+K)A < 0.5 and CaA < 0.5. Amphibole in (a) is AI-rich while amphibole in (b) is AI-poor. Amphibole. Sangan Khaf granitoid. garnet-pyroxene skarn. amphibole skarn ferroedenite. hastingsite and ferroactinolite. 2002 4 01 67 80 http://ijcm.ir/article-1-831-en.pdf
51-832 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 Growth of MnCI2.4H20 crystals and measurement the exact percent of cobalt impurities in the crystal, using radioactive isotopes of 54Mn, 60Co, 57CO and NMRON technique In this paper, MnCl,.4H,O crystals with monoclinic structure, for the study of magnetic hyperfine field in magnetic crystal at low temperature, have been grown. To study the effect of impurities on T, (spin-lattice relaxation time), crystals with different percent of "Co impurities, from saturated mixed solution of MnCl,.4H,O and CoCl,.6H,O at temperature of 30Q'K, have been grown. The percent of cobalt impurities in the solution and crystal was determined by using the radioactive isotopes of "Mn, 6OCO and "Co as probes. The result indicated that the ratio of "Co/"Mn was about 6.2% which has a good correspondence with the results of the NMRON spectrum of 54Mn in low temperatures (T<lOOmK). CoCI2.6H20 MnCI2.4H]O NMRON (Nuclear Magnetic Resonance on Oriented Nuclei) and Antiferromagnetic 2002 4 01 81 86 http://ijcm.ir/article-1-832-en.pdf
51-833 2024-03-29 10.1002
Iranian Journal of Crystallography and Mineralogy www.ijcm.ir 1726-3689 2588-4719 10.61186/ijcm 2002 10 1 Study of Transformation of Clay Minerals in the Interaction Process with Additives by uS,e of Scanning Electron Microscope and XRD and its Relation to Mechanical Behaviour of Soil The use of lime as additive to soil is a very common technique in engineering projects. The purposes of this proceses are the increase in strength and a decrease in plasticity behaviour of the soil. The results of this research indicate that in the chemical interaction process of soil minerals with lime, a part of minerals, specifically clay minerals, transform to other minerals. In fact, this transformation is the base for the different mechanical response of soil. In the present study, attention is made to the tri-calcium-silica-hydrate (CSH), tetra-calcium-alumnahydrate (CAH), and ettringite, as the three major minerals formed in this process. This transformation is monitored by use of scanning electron microscope and x-ray diffraction testing. Clay mineral Lime Ettringite Tri-Calcium-SilicaHydrate Tetra-Calcium-Alumina-Hydrate 2002 4 01 87 97 http://ijcm.ir/article-1-833-en.pdf