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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.

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 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.

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.