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Mansurov Z.A.,Al-Farabi Kazakh National University | Shabanova T.A.,Al-Farabi Kazakh National University | Mofa N.N.,Al-Farabi Kazakh National University | Glagolev V.A.,Satpaev Institute of Geological science
Eurasian Chemico-Technological Journal

The concept morphostructure formations nanosized individuals on the basis of carbon and quartz is offered. Under offered circuit in "the first stage" substances are generated by atoms - "elementary individuals". They - form "simple morphostructures", for example, fullerenes, film and a one-wall carbon tube. They have, at the best the two-dimensional structural order. The second stage of growth morphostructures is connected to formation of more complex of "elementary particles" on the basis of the approximated rounded molecules. They - form "simple morphostructures", for example, fullerenes, film and carbon tube also. The third stage - clusters. Clusters, similarly to atoms and molecules, can form cyclic formations (oligomer/polymers), crystals and can enter structure of the mixed constructions of a layer. They can form also simple morphostructures, for example, fullerenes, film and carbon tube. The fourth stage - compact formations of polymer and so on. © 2012 al-Farabi Kazakh National University. Source

Li J.,Hebei United University | Li J.,CAS Institute of Geology and Geophysics | Xu Y.,Hebei United University | Shen P.,CAS Institute of Geology and Geophysics | And 4 more authors.
Scientia Geologica Sinica

The ore body of skarn type deposit in Sayak is located in the contact zone between Carboniferous limestone and granite, surrounded by skarn. The skarn minerals in Sayak mainly include garnet, pyroxene, epidote and chlorite. Metallic minerals are mainly chalcopyrite, bornite, pyrite, pyrrhotite, cobaltite. The mineralization of Sayak deposit can be divided into five metallogenic stages: Diopside-garnet skarn stage, garnet skarn stage, epidote-magnetite stage, quartz-sulfide stage and carbonate stage. Electron microprobe analyses show that skarns in Sayak belong to typical calcic skarns. There are three types of garnet in skarn, and they all belong to andradite-grossularite solid solution series. The garnet shifted from andradite towards andradite-grossularite with time, and the andradite-grossularite is most relevant to the mineralization besides. The content is changing with the zone rhythmically, which means that its growth is discontinuity indicating multi-stages of fluid. The pyroxenes are mainly composed by diopside with a small amount of hedenbergite. The epidote is almost epidote with a little clinozoisite. The magnetite is composed by a high TFeO content with a negative correlation with other oxide. Chalcopyrite-pyrite-pyrrhotite-marcasite and chalcopyrite-cobaltite are developed in early quartz-sulfide stage, while compact massive chalcopyrite formed in the later main stages. The chalcopyrite and pyrite are both lean sulfur and rich metallic element, and pyrrhotite is lean cobalt but rich nickel. The mineralogical features such as paragenetic association of skarn minerals and the composition evolution of garnet indicated that the ore-forming hydrothermal evolved from alkalescence to acidity as the decrease in temperature and oxygen fugacity. Meanwhile the chalcopyrite-based metal sulfides occurred enrichment and precipitation with the neutralization in the contact zone. ©, 2015, Science Press. All right reserved. Source

Shen P.,CAS Institute of Geology and Geophysics | Pan H.,Changan University | Seitmuratova E.,Satpaev Institute of Geological science | Yuan F.,Hefei University of Technology | Jakupova S.,Satpaev Institute of Geological science

The Bozshakol area is one of the most important copper resource concentrations in Central Kazakhstan. We report in situ zircon U-Pb age and Hf isotope data, whole rock geochemical and Sr-Nd isotopic data for the volcanics and intrusions from the Bozshakol area.Secondary ion mass spectrometry (SIMS) zircon U-Pb dating indicates that the volcanics erupted at 501.8±3.2Ma and the intrusions emplaced at 489.5±3.3Ma. The volcanics are subdivided into two types. Type I are tholeiitic to calc-alkaline basalt and calc-alkaline andesite and dacite, which are enriched in light rare earth elements (LREE) with a marked negative Nb anomaly and Th/Yb-enrichment. They also have low initial 87Sr/86Sr ratios (0.7026-0.7048), high zircon εHf(t) and whole-rock εNd(t) values (+9.7 to +17.0 and +5.4 to +6.7, respectively). Type II are Nb-enriched basalts (NEBs, Nb=6-7ppm), which are sodium-rich (Na2O/K2O=3-10) and differ from the vast majority of arc basalts in their higher Nb, Zr, and TiO2 contents and Nb/U ratio. NEBs also have low whole-rock initial 87Sr/86Sr ratios (0.7040) and high εNd(t) values (+5.6). Therefore Bozshakol volcanics were formed by partial melting of the mantle wedge and subducted slab.The Bozshakol ore-bearing intrusive rocks include the fine- and medium-grained tonalite porphyry. They belong to the medium-K calc-alkaline series and are strongly enriched in LREE with a marked negative Nb anomaly and Th/Yb-enrichment. The fine-grained tonalite porphyries exhibit element characteristics similar to normal arc granitoids. They have low initial 87Sr/86Sr ratios (0.7036-0.7039), high zircon εHf(t) values (+10.7 to +17.2) and whole-rock εNd(t) values (+4.9 to +5.7). Compared with the fine-grained tonalite porphyries, the medium-grained tonalite porphyries have high Al2O3 and Sr contents (16-17wt.% and 565-569ppm, respectively) and low Yb and Y concentrations (0.9-1.1ppm and 9.3-12.1ppm, respectively), showing a geochemical affinity to adakites. Therefore, Bozshakol intrusive rocks were also derived from the mantle wedge and minor slab melts. We propose a model of intra-oceanic subduction for the Middle to Late Cambrian magmatic evolution of magmatic arcs in northwestern central Kazakhstan. © 2015 Elsevier B.V. Source

Shen P.,CAS Institute of Geology and Geophysics | Pan H.,Changan University | Seitmuratova E.,Satpaev Institute of Geological science | Jakupova S.,Satpaev Institute of Geological science
Journal of Asian Earth Sciences

Nurkazgan, located in northeastern Kazakhstan, is a super-large porphyry Cu-Au deposit with 3.9 Mt metal copper and 229 tonnage gold. We report in situ zircon U-Pb age and Hf-O isotope data, whole rock geochemical and Sr-Nd isotopic data for the ore-bearing intrusions from the Nurkazgan deposit. The ore-bearing intrusions include the granodiorite porphyry, quartz diorite porphyry, quartz diorite, and diorite.Secondary ion mass spectrometry (SIMS) zircon U-Pb dating indicates that the granodiorite porphyry and quartz diorite porphyry emplaced at 440 ± 3 Ma and 437 ± 3 Ma, respectively. All host rocks have low initial 87Sr/86Sr ratios (0.70338-0.70439), high whole-rock εNd(t) values (+5.9 to +6.3) and very high zircon εHf(t) values (+13.4 to +16.5), young whole-rock Nd and zircon Hf model ages, and consistent and slightly high zircon O values (+5.7 to +6.7), indicating that the ore-bearing magmas derived from the mantle without old continental crust involvement and without marked sediment contamination during magma emplacement. The granodiorite porphyry and quartz diorite porphyry are enriched in large ion lithophile elements (LILE) and light rare earth elements (LREE) and depleted in high-field strength elements (HFSE), Eu, Ba, Nb, Sr, P and Ti. The diorite and quartz diorite have also LILE and LREE enrichment and HFSE, Nb and Ti depletion, but have not negative Eu, Ba, Sr, and P anomalies. These features suggest that the parental magma of the granodiorite porphyry and quartz diorite porphyry originated from melting of a lithospheric mantle and experienced fractional crystallization, whereas the diorite and quartz diorite has a relatively deeper lithospheric mantle source region and has not experienced strong fractional crystallization. Based on these, together with the coeval ophiolites in the area, we propose that a subduction of the Balkhash-Junggar oceanic plate took place during the Early Silurian and the ore-bearing intrusions and associated Nurkazgan porphyry Cu-Au deposit occurred in an intra-oceanic arc setting. © 2015 Elsevier Ltd. Source

Stepanov A.V.,Satpaev Institute of Geological science | Bekenova G.K.,Satpaev Institute of Geological science | Levin V.L.,Satpaev Institute of Geological science | Hawthorne F.C.,University of Manitoba
Mineralogical Magazine

Natrotitanite, ideally (Na 0.5Y 0.5)Ti(SiO 4)O, is a new mineral from the Verkhnee Espe rare-element deposit at the northern exo-contact of the Akjailyautas granite massif in the northern part of the Tarbagatai mountain range, Eastern Kazakhstan. Both the mineral and the name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA 2010-033). Star-shaped aggregates of small short prisms of yellow or yellowish white (Na,Y,REE)-bearing titanite rimmed by thin (∼2 μm) rims of natrotitanite are embedded in yttrium-bearing fluorite and replace narsarsukite. Associated minerals are microcline, albite, quartz, riebeckite, aegirine, biotite, astrophyllite, rutile, zircon and elpidite. Natrotitanite is milky white to yellowish grey, transparent to translucent, and has a white streak and a vitreous lustre. It shows pale orange cathodoluminescence but does not fluoresce under ultraviolet light. It shows no cleavage or parting, and is brittle; the calculated density is 3.833 g cm -3. The indices of refraction, measured with the Bloss spindle stage for the wavelength 590 nm using a gel filter, are α = 1.904, γ = 2.030, and these values are in accord with the mean refractive index, 1.988, calculated from the Gladstone-Dale relation. Natrotitanite is monoclinic, C2/c, a = 6.5691(2), b = 8.6869(3), c = 7.0924(2) Å, β = 114.1269(4)°, V = 369.4(2) Å 3, Z = 4, a:b:c = 0.7562:1: 0.8164. The seven strongest lines in the X-ray powder diffraction pattern [in the order d (Å), I, (hkl)] are as follows: 2.597, 10, (130); 3.248, 8, (112); 2.994, 6, (200); 1.641, 4, (330); 4.941, 3, (110); 1.498, 3, (400); 2.273, 3, (113). Chemical analysis by electron microprobe gave Nb 2O 5 1.28, SiO 2 27.83, TiO 2 35.00, SnO 2 0.57, V 2O 3 0.36, Fe 2O 3 0.23, Y 2O 3 7.87, Ce 2O 3 0.83, Sm 2O 3 0.26, Gd 2O 3 0.46, Tb 2O 3 0.17, Dy 2O 3 2.45, Ho 2O 3 0.16, Er 2O 3 2.24, Tm 2O 3 0.50, Yb 2O 3 2.53, Nd 2O 3 0.35, Lu 2O 3 0.28, MnO 0.33, CaO 8.16, Na 2O 5.55, F 1.52 O F -0.64, sum 98.71 wt.%. The resulting empirical formula is (Na 0.39Ca 0.32Y 0.15Dy 0.03Yb 0.03Er 0.03Ce 0.01Ho 0.01Tm 0.01Gd 0.01Nd 0.01) Σ1.00(Ti 0.95Nb 0.02Sn 0.01Fe 3+ 0.01Mn 0.01V 0.01) Σ1.01Si 1.01O 4.00(O 0.83F 0.17), calculated on the basis of 3 cations per formula unit. The general formula is written as (Na,Ca,Y,REE)TiSiO 4(O,F), and the endmember formula is (Na 0.5Y 0.5)Ti(SiO 4)O. The crystal structure of a composite optically continuous crystal of natrotitanite and (Na, Y)-bearing titanite was mounted on a Bruker D8 three-circle diffractometer equipped with a rotating anode generator (MoKα radiation), a multi-layer optics incident-beam path and an APEX-II CCD detector. The crystal structure was refined in space group C2/c to a final R 1 index of 1.8%. Natrotitanite is isostructural with titanite, (Na + Y + REE) replacing Ca at the Ca site in the titanite structure. © 2012 Mineralogical Society. Source

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