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The authors' determinations of the U–Pb isotopic age of zircon (LA–ICP–MS method) in the main types of igneous rocks emphasize the presence of both Neogene and older (up to Late Paleozoic) intrusions at the deposit. The earliest are rocks of the “trondhjemite” massif, which were emplaced in the Late Paleozoic. This age of the rocks of the trondhjemite massif, confirmed by the U–Pb isotopic method (302 ± 4 Ma) for zircon from rocks of its main intrusive phase (tonalites–granodiorites), is consistent with manifestation of Late Paleozoic tungsten-bearing magmatism and associated W mineralization in the North Caucasus (in the Peredevoi Range) and allows a possible Late Paleozoic age of large bodies of altered skarns with W mineralization at the Tyrnyauz deposit. At the next, Neogene stage, the intrusion of leucocratic granites took place with the formation of bodies of igneous breccias, the emplacement of an accompanying aplite dike formation, and the development of intense molybdenum (with subordinate W) mineralization in large vein–veinlet, stockwork systems. The U–Pb isotopic age of zircon in leucocratic granites is 2.67 ± 0.04 Ma. Later, a large massif of biotite (Eldzhurt) granites and associated formation of aplite and alaskite dikes were formed. Emplacement of subvolcanic rhyolite bodies followed. The U–Pb isotopic age of zircon in the Eldzhurt granites is 2.10 ± 0.08 Ma, and in rhyolites, 2.05 ± 0.04 Ma. Intrusion of these rocks was accompanied by the formation of Mo–W–Bi–Te–Au mineralization.

The isotopic U–Pb ages are estimated for zircons (for the first time by the LA–ICP–MS method) from biotite (Eldzhurty) granites and for the first time from the rhyolites at the giant Tyrnyauz Mo–W deposit (North Caucasus). The weighted mean isotopic U–Pb age of zircon from the Eldzhurty granites is 2.10 ± 0.08 Ma, with variations from 1.78 to 2.53 Ma, whereas that of zircon from the rhyolites is 2.05 ± 0.04 Ma, with variations from 1.81 to 2.42 Ma. These data confirm the Neogene (Pleistocene) age of the rock crystallization, are in agreement with the emplacement sequence, and emphasize the short time span (~50 ky) between them.

The first data of a U–Pb isotopic study (LA-ICP-MS method) of zircon from leucocratic granites of the giant Tyrnyauz Mo–W deposit (North Caucasus) are presented. The emplacement of this granite separated the formation stages of Mo–W skarns and younger large stockworks with Mo-mineralization. Two types of zircons are distinguished among the grains identified. The first type is represented by rare tabular and short-prismatic crystals (xenocrysts) of an ancient zircon, with large variations of the U–Pb isotopic age (from about 300 Ma to almost 1500 Ma). The second type includes more abundant long-prismatic crystals of a young zircon; its weighted average U–Pb isotopic age (2.67 ± 0.04 Ma) corresponds to the time of leucocratic granite crystallization.

—Based on new geochronological data on gabbroid and plagiogranitoid associations (Tavan-Hayrhan, East Bayan Tsagaan, Bayan Tsagaan Uul, Tungalag, Three Hills, and Shutkhuin massifs) located among the Vendian island-arc volcanic complexes of the Lake Zone of Western Mongolia, an independent stage of Vendian island-arc intrusive magmatism (560–542 Ma) is substantiated. Geochronological ages determined by xenogenic zircon from Vendian gabbroids and granitoids (716–559 Ma) indicate a wide time interval of their formation and different natures of the sources. Several such sources are assumed. The source of the first type is rocks of the late Riphean oceanic crust of the Paleoasian Ocean, on which the Vendian island arc of the Lake Zone formed later. This is evidenced by the presence of xenogenic zircon with the ages of ~716, 658–642, 613–611 Ma. The source of the second (probably main) type is rocks of the Vendian island-arc crust of the Lake Zone. This is indicated by the presence of xenogenic zircon with ages of 583–559 Ma, observed in all studied Vendian intrusive associations.

The first data of U–Pb isotopic study (LA–ICP–MS method) of zircon from tonalite–granodiorite forming a dominant part of the “trondhjemite” intrusive massif at the giant Tyrnyauz W–Mo deposit (North Caucasus) is presented. The concordant zircon isotopic U–Pb age obtained (302 ± 4 Ma) indicates a Late Paleozoic (Late Carboniferous–Early Permian) age of crystallization of these rocks. This is consistent with the Late Paleozoic epoch of W-bearing magmatism and related W mineralization in the North Caucasus (Peredovoi Ridge) and allows the possibility of the Late Paleozoic age of the large bodies of altered skarn with W mineralization at the Tyrnyauz deposit.

Studies of volcanic rocks in orogenic troughs of Eastern Kazakhstan were carried out. The troughs were formed at late-orogenic stages of evolution of Hercynian Altai collision system. Volcanic rocks are represented by basalts, andesites, dacites and rhyolites. Based on geochemical and isotopic data, the basalts and andesites derived from mafic magmas that formed as a result of partial melting of garnet peridotites in the upper mantle under the orogen. U–Pb zircon data prove two volcanic stages: more-scaled Middle Carboniferous (~311 Ma) and less-scaled Early Permian (297–290 Ma). Basalts and andesites in lower parts of the orogenic troughs and independent dacite-rhyolite structures were formed at the Middle Carboniferous stage. Parental mafic magmas were formed as a result of partial melting of mantle substrates in local transtensional zones along large shear faults. The formation of dacites and rhyolites could have been caused by partial melting of crustal substrates under effect of mafic magmas. Transtensional movements in the lithosphere of orogenic belts may indicate the beginning of collapse of orogens. A smaller volume of basalts and andesites formed at the Early Permian stage. Geochemical data prove the independent episode of partial melting in upper mantle. Synchronous basalts and andesites also appeared at wide territory in Tian Shan, Central Kazakhstan, and Central and Southern Mongolia. Early Permian volcanism indicates general extension of the lithosphere at the postorogenic stages. Large-scaled Early Permian mafic and granitoid magmatism in Central Asia has been interpreted in recent years as the Tarim Large Igneous Province caused by Tarim mantle plume activity. Thus, the extension of the lithosphere and associated volcanism in the Early Permian can be an indicator of the onset of the plume–lithosphere interaction process.

The results of U–Th–Pb LA-ICP-MS dating of detrital zircons collected from the Permian–Triassic red beds of the Moscow Basin are presented. U–Th–Pb ages of detrital zircons from two samples (Upper Permian and Lower Triassic), which were collected in the vicinity of the P–T boundary in the Zhukov Ravine reference section, show their contrasting provenance. It means that U–Pb detrital zircon geochronology can be used as an additional independent tool for stratigraphic correlation of the Permian–Triassic red beds, at least within the Moscow Basin. The applicability of the method is illustrated by additional constraints on the age of the Nedubrovo member deposits (Vologda Region) with a previously uncertain stratigraphic position: the U–Pb age pattern of the respective detrital zircons suggests their Early Triassic age.

The paper presents new original data on the Devonian felsic volcanism of the NW Rudny Altai (Russia) in the west of Central Asian Orogenic Belt (CAOB) – the front part of the Altai convergent margin of the Siberian continent. Two geochemical types of subvolcanic rhyolites were emplaced synchronously with the bimodal rhyolite-basalt association, which began to form in the end-Emsian, and clearly manifested on the border of the Givetian and the Frasnian. The rhyolites yield zircon U-Pb ages of ca. 390 Ma (R1-type) and 380 Ma (R2- and R3-types), reflecting two peaks of the volcanic activity. Most of these rocks have extreme petrochemical characteristics of high SiO2 contents and have contrast Na/K ratios. Their compositions are transition between calc-alkaline and tholeiite series: (La/Yb)n ~ 2–7, Zr/Y ~ 4 (Zr 350 ppm), Zr (>250 ppm), and high Ga/Al (>2.6) values. The island-arc-like R1-rhyolite formed immediately after the beginning of rifting due to widespread crustal melting under reduced conditions. The generation of rift-like R2- and R3-rhyolites took place under non-equilibrium conditions, synchronously with the rise in the upper crust of Givetian-Frasnian basic magmas, as a result of the active lithospheric extension and high thermal input from the underlying hot mantle. We propose an extension regime in the transition area between the island-arc and back-arc basin for the origin of rhyolites. The study of the Devonian volcanism of the Rudny Altai gives important information about the processes that occurred at the initial stage of the formation of the Altai convergent margin.

The magneto-optical properties of magnetic nanocomposites have been studied in the study of spectral dependences of the transverse Kerr effect (TKE). Experimental preparation of nanocomposites formed from FeCoZr and Al2O3 alloys at different component concentrations by ion-beam sputtering is discussed. Discuss various methods of the theoretical study of nanocomposites depending on the concentration of ferromagnetic components. The spectral dependences of TKE at low concentrations of the metal component are investigated. Spectral dependences of the Kerr transverse effect are simulated in the framework of the TKE are compared taking into account the size effect at different values of the nanocomposite granule size. There is a good qualitative and quantitative agreement between experimental and theoretical spectral dependences of TKE. In addition, in this paper, we note both practical and fundamental importance of the results. The possibilities of using such nanocomposite materials are discussed.

Late Albian-early Cenomanin epoch of Au-Cu porphyry mineralization has been distinguished within the Sikhote-Alin. It is associated with the Alb-Cenomanian granitic rocks which emplacement coincided with the processes of orogeny and neoformation of continental lithosphere caused by compressive stress in the setting of transform continental margins of that time. The intrusion of the granitic magma into the crust of Jurassic accretionary wedge terranes and Early Cretaceous terrane of epicontinental turbidite basin provoked development of Au-Mo-Cu and Cu-Au-W ore genesis, respectively. U-Pb dating of zircons from host granites of the Malmuzh Au-Cu deposit yielded Alb-Cenomania age of 100-95 Ma. This age harmonizes with the age data reported by other researchers on the granitic rocks of East and Southeast Asia which are productive for hydrothermal mineral deposits of copper, gold, tin and other metals. Such age consistency suggests that there is Albian-Cenomanian metallogenic megabelt extending throughout the entire East Asian continental margin.

The Late Albian–Early Cenomanian epoch of Au-Cu porphyry ore mineralization has been distinguished within the Sikhote-Alin. The development of ore mineralization is associated with Albian–Cenomanian granitoids, synchronous to syn-strike-slip orogenesis and the formation of the continental lithosphere in the setting of transform continental margins. The development of Au–Mo–Cu and Cu–Au–W types of ore mineralization in the terrains of the Jurassic accretionary prism and the Early Cretaceous terrain of the epioceanic turbidite basin, correspondingly, was induced with the mantle–crustal synorogenic intrusions of granitoids. The U–Pb zircon dates (100–95 Ma, Albian–Cenomanian) of Au–Cu porphyry Malmyzh granitoids are given for the first time. The similar data available on the age of granitoids in Eastern and Southeastern Asia, which are associated with plutonogenic–hydrothermal deposits of Cu, Au, Sn and other metals, allow us to suggest that there is an Albian–Cenomanian metallogenic megabelt extending along the entire Pacific continental margin of Asia.

Two methods — ICP-MS and ICP-AES are used for certification of the new reference material — needles of Siberian pine (NSP-1). Techniques of the analysis include decomposition of plant samples in two different ways: acid digestion in a microwave system MARS-5 and lithium metaborate fusion followed by ICP-MS and ICP-AES analysis of the solutions. Simultaneous determinations of all the elements were carried out in low, medium and high resolution using SF-mass-spectrometer ELEMENT and atomic-emission spectrometer IRIS Advantage with external calibrations and internal standards (In — ICP-MS, Sc —ICP-AES). Middle and high resolutions of ICP mass spectrometer were used for interference corrections. Data obtained by ICP-MS and ICP-AES with different decomposition techniques are in good agreement. The ICP-MS and ICP-AES techniques have been validated by the analysis of three plant reference materials: LB-1 (leaf of a birch), Tr-1 (grass mixture) and EK-1 (Canadian pondweed). These techniques were used for the determination of 38 elements in the new reference material NSP-1. Relative standard deviations for most of the determined elements were below 10%. Combination of ICP-MS and ICP-AES techniques for certification of the new reference material makes it possible to expand the set of elements to be determined and to reduce the total analysis time.

—The Bayan-Kol gabbro–granite association has been recognized within the West Sangilen fragment of collision zone in the northwestern framing of the Tuva–Mongolian massif, and its composition, age, and tectonic and geodynamic settings have been studied. The association includes the Bayan-Kol pluton and composite (mingling) dikes, which formed in the late collision period (495 ± 5 Ma), during the transition from transpression to extension mode with left-lateral strike-slip kinematics. The Bayan-Kol gabbro–granite association is spatially confined to the penetrating tectonic zones of the West Sangilen shear system. The position of gabbroid and granite bodies is controlled by local zones of tectonic extension. Basic magmas have a similar petrogeochemical composition, which indicates their intrusion from a single chamber of basic composition and differentiation of ascending magma. The melting, transfer, and formation of crustal granitoids of the Bayan-Kol association are genetically related to the thermal effect of basic melt and a syntectonic drop in lithostatic pressure. The intrusion and formation of basic and acid melts of the Bayan-Kol association took place at the lower and middle crustal levels in the settings of the reactivation and subsequent fragmentation of the tectonic zone.

Spectral dependences of the transverse Kerr effect (TKE) are studied in (CoFeZr)x(Al2O3)(1 − х) magnetic nanocomposites. TKE spectra are modeled for an unannealed composite using the Maxwell–Garnett approximation (MGA) in an effective medium. TKE calculations are made by considering the particle sizes of the nanocomposite (the quasi-classical size effect). The experimental data are found to be consistent with the theoretical TKE spectra.

The phase composition, structure, elemental distribution, and hydrolytic stability of quench-hardened and tempered sodium-aluminum-phosphate (SAP) and sodium-aluminum(iron) phosphate (SAIP) glass materials containing 10 wt.% (above 100%) oxides of rare earth elements (REE) were studied. It is shown that all materials obtained by quench-hardening melts (except La-containing melts) were x-ray amorphous, while slowly cooled (tempered) melts partially or completely crystallized with different phases of orthophosphates being released. The rate of leaching of elements from tempered SAP glasses determined at 90°C is approximately one or two orders of magnitude higher than then for the quench-hardened glasses, and the leach rate of elements from quench-hardened SAIP glasses is lower than from quench-hardened SAP glasses.

The Glafirinskoe and related skarn Cu-Au (+Mo, W) deposits represent an Early Paleozoic (Late Cambrian to very early Ordovician) mineralization in the Altaid Belt, also known as the Central Asian Orogenic Belt. They are associated with multiphase plutons of high-K calc-alkaline to shoshonitic rocks that are related to a low-degree partial melting of metasomatically-enriched upper mantle, followed by amphibole fractionation in a deep (lower crustal ?) magma chamber and then by magma fractionation and emplacement at shallower crustal levels. Isotopic U-Pb zircon dating of the igneous rocks yields early Ordovician (ca. 480–478 Ma and 483 Ma) age. These rocks were emplaced in a continental magmatic arc after the Late Cambrian collision, in a post-collisional setting involving the stall and break-off of the subducting slab during the Late Cambrian to Early Ordovician. The deposits comprise prograde and retrograde skarns that are characterized by abundant andradite-rich garnet, which defines their oxidized type. Wider zones of potassic (quartz-K-feldspar) and calc-potassic (quartz-K-feldspar-calcite-garnet) alteration occur in the igneous rocks, with their further overprint by propylitic (with abundant scapolite) and phyllic (carbonate-phyllic) alteration. All these alteration assemblages bear abundant chalcopyrite and minor bornite. Phyllic alteration assemblages also contain various As, Sb, Pb, Zn, Co, Ni sulfides and sulfosalts, tellurides, Bi minerals, and native Au. Scheelite and/or molybdenite are locally present in some mineralized zones. The Cu-Au-Mo(-W) mineralization occurs as skarn orebodies that are spatially associated with porphyry-style alteration assemblages reflecting the high exploration potential for additional, but concealed, skarn-porphyry Cu-Au-Mo deposits in the vicinity. The retrograde skarn and potassic (calc-potassic) alteration assemblages were formed from high temperature (570–580 °C), high salinity , aqueous chloride magmatic-hydrothermal fluid, with its boiling and phase separation indicating hydrostatic conditions at a relatively deep (~6 km) skarn-porphyry environment. Propylitic alteration assemblages were formed at lower temperatures (~380–420 °C) from a Ca-Na-chloride, low salinity (~8 wt% NaCl-eq.) magmatic-hydrothermal fluid. Fluid inclusions in minerals from phyllic alteration assemblages indicate the influx of a CO2-rich fluid at about 270–290 °C and 1400 ± 50 bars and subsequent mixing with more saline (20 wt% NaCl-eq.) and cooler (~240 °C) hydrothermal fluids.

Accretionary-collisional events occurred at the western margin of the Tuva-Mongolian microcontinent are used to explain the largely contradictory Cambrian geodynamic history of the western Central Asian Orogenic Belt (CAOB). This study presents new data for the Erzin metamorphic complex in order to constrain the petrogenesis and tectonic implications of the metamorphic rocks in this complex. The Erzin complex in the tectonic Erzin zone is composed of high-grade metamorphic rocks that have formed under variable metamorphic conditions (T = 730–835 °C, P = 5.3–7.5 kbar). In the Erzin complex, metamorphic rocks have undergone multiple stages of ductile deformation with subvertical mineral lineation and were then superimposed by sub-horizontal ductile deformation. The stages of tectonic deformation are close in time and mark collisional stages characterized by a sequential change from the compression regime to the extension regime in the period of 495 ± 5 Ma. The determination of the time interval is based on structural and petrological data, previously published materials, as well as the dating of granite dikes (U-Pb, zircon) sealing the Erzin complex. P-T conditions and structural-petrological studies analysed in this paper suggest that the formation of the Erzin metamorphic complex occurred as a result of a collisional event between the Tannuola island arc and Tuva-Mongolian microcontinent. We suggest that the Erzin metamorphic complex is important for study of transitional regime between the collisional event and initial orogenic collapse in the ancient fold belts. Metamorphic record of the Tuva-Mongolian microcontinent provides important information about the processes that occurred at the Early Paleozoic geodynamic evolution in the western CAOB.

This is a synthesis of published and new data on the Kalba batholith in Eastern Kazakhstan, the large granitic body in the western part of the Central Asian Orogenic Belt. The batholith consists of granodiorite-granite and leucogranite rocks discriminated on the basis of major- and trace-element chemistry and isotope systematics. The granodiorite-granite rocks, which form the bulk of the batholith, are compositionally variable and can be classified as mixed S-I-type granites. The leucogranites occurring as a few large intrusions in the northwestern part of the batholith have more stable compositions, with high contents of REE, HFSE, F, Li, and B, typical of A-granites. Judging by the isotope systematics of the Kalba granites, compared with that of their potential parent rocks from the Kalba-Narym zone and its surroundings, the two groups originated by different mechanisms in two magmatic events. The granodiorite-granites were produced by large-scale melting of crustal material, including the metabasaltic basement and overlying metavolcanic and metasedimentary rocks. The origin of leucogranites was associated with low-degree partial melting of the deepest Kalba-Narym sediments under the effect of fluoride fluids. The batholith formation spanned about 21 myr: granodiorites and granites formed in the 297–286 Ma interval and leucogranites between 288 and 276 Ma. The ages of the two events bracket the intraplate postorogenic stage of the CAOB history that was coeval to the formation of the Tarim large igneous province.

The paper is concerned with the experimental spectral dependence of the magneto-optic Kerr effect for samples of nano-layered films of Co-Au. Theoretical spectral dependences of the ‘Transversal Kerr Effect’ are constructed. Spectral dependences taking into account the size effect are given. Theoretical and experimental data are compared. There is good agreement between experimental and simulated results. The relevance of this research area and the results obtained are noted. Discussed the possibility of using such nano-layered thin films structures.

The magnetooptical spectra of the transverse Kerr effect of (CoFeZr)x(Al2O3)1-x nanocomposites are calculated within the framework of the symmetrized Maxwell-Garnett (SMG) approximation. The quasi-classical size effect and the size distribution of the granules were taken into account. The calculation results for the spectral range 0.5-3.5 eV and different concentrations of the magnetic component are in semi-quantitative agreement with the experimental data. A possible reason for the existing discrepancy is the difference between the optical and magneto-optical parameters of ferromagnetic granules from those corresponding for bulk samples.

Carbon micro- and nanoscale structures formed during the consolidation of magmatic rocks is investigated. They are very similar to nanoscale carbon structures synthesized in a laboratory. A wide range of elements (Fe, K, Ti, V, Cr, Mn, Ni, Pt, Zn, Ga, Ge, Br, Sr, Zr, and Pb) are identified by XRF analysis in natural globules of graphite containing micro- and nanoscale structures. Some of these elements are thought to be natural catalysts in the formation of carbon structures by chemical vapor phase deposition (CCVD); the rest (rare-earth and noble metals) are considered to be useful as indicators of host rock mineralization.

1193 Finds of graphite, bitumen, and carbonaceous matter in magmatic rocks and ores of various compo� sitions provide evidence for the participation of hydro� carbon fluids in petrogenesis and ore formation. Hydrocarbons are able to extract chemical elements and transport them as element-organic compounds and produce carbonbearing phases and ore concen� trations upon dissociation (1). Consequently, the asso� ciation of graphite and noble metals in ores is not acci� dental and explains the relationships between the high concentrations of platinoids and graphite and/or bitu� men occurrences in "tubes" of the Nizhnii Tagil Mas� sif (2), in dunite pipes (3, 4), and in Merenskii reef of Bushveld (5), in ores of Stillwater (6), and in deposits of the Norilsk and Dzhaltul-Khungtukunskii types (7-9). Detailed study of graphite on the microstruc� tural level in was not carried out for these objects. Cur� rently researchers are greatly interested in nanosized graphite manifestations known as graphenes, fullerenes, graphite tubes, and other structured forms of carbon. The optimal conditions of obtaining of var� ious nanomaterials are now being studied. Until now finds of carbon nanostructures in natural objects have been extremely rare. Graphite nanostructures from metamorphic rocks of the Grenville province (Can� ada) and graphitebearing alkaline pegmatites of the Kola Peninsula (10, 11) are examples of those close to synthetic structured carbon by morphology. Natural microand nanostructures of graphite are of special scientific interest for understanding the possible con� ditions and mechanisms of their formation (12), as well as the possible participation of metal-organic compounds in this process.

We consider a problem on an ellipsoidal inhomogeneity in an infinitely extended homogeneous isotropic elastic medium. The inhomogeneity differs from the ambient body in the elastic moduli (Poisson’s ratio ν and shear modulus µ) and in that it has intrinsic strains. We use the equivalent inclusion method to write out expressions for the Helmholtz and Gibbs free energy of the inhomogeneity as quadratic forms in the intrinsic strains and strains at infinity. The general expressions for the coefficients of these quadratic forms are written out as three rank four tensors characterizing the contribution to the energy by the plastic strain (ɛp2), by the strain at infinity (ɛ02), and (only for the Gibbs energy) by the cross term ɛ0ɛp.