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listelement.badge.dso-typeЭлемент, ISOTOPIC PROVINCES AND FORMATION STAGES OF THE CONTINENTAL CRUST IN THE BAIKAL-MUYA BELT: Sm-Nd ISOTOPIC EVIDENCE FOR GRANITIC AND SILICIC VOLCANIC ROCKS(2007) Rytsk E.Y.; Kovach V.P.; Yarmolyuk V.V.; Kovalenko V.I.Recent geological, geochronological, geochemical, and isotopic data made it possible to establish the main stages of the formation and evolution of the oceanic and continental crusts of the Central Asian Foldbelt (CAFB), to outline isotopic provinces, and to elaborate geodynamic models of the crust formation related to the origin and breakdown of Rodinia and Gondwana supercontinents. Nevertheless, many problems related to the earliest, Late Riphean–Vendian periods of the geological history remain a matter of debate due to the lack of isotopic geochronological and geochemical data. The Baikal fold region as a tectonotype of the Baikalides is the key domain for solving these problems. This communication is a synthesis of the original geochronological and Nd isotopic data on granitic rocks and silicic volcanics of the Baikal–Muya Belt (BMB) of the Baikal fold region. Isotopic provinces and formation stages of the crust are outlined on the basis of these data.listelement.badge.dso-typeЭлемент, NEW DATA ON THE PLATINUM POTENTIAL OF HYDROTHERMAL FORMATIONS IN THE UPPER AMUR REGION(2007) Mel'nikov A.V.; Radomskii S.M.; Moiseenko V.G.; Mel'nikov V.D.Until recently, industrial deposits of platinum group elements (PGE) were only recognized in two petrogenetic classes. The magmatic class included liquation, early magmatic, and late magmatic deposits. The sedimentary class was represented by placers. Recently, they have been complemented with industrial deposits of Pt and PGE of metamorphic and hydrothermal classes. Deposits in black shales and their metasomatic rocks (unconventional or complex Au–Pt deposits) have the highest Pt potential among these petrogenetic classes. Pt-bearing hydrothermal deposits are widespread in the upper Amur region. They have been explored over a long period and are characterized by significant resources.listelement.badge.dso-typeЭлемент, COPPER-GOLD-PALLADIUM MINERALIZATION IN ULTRABASIC ROCKS OF THE POLAR URALS(2007) Kuznetsov S.K.; Filippov V.N.; Onishchenko S.A.; Kotel'nikov V.G.The northern Ural region incorporates several large ultrabasic massifs (Voykar-Osa, Rai-Iz, and Syum-Keu) confined to the Polar Ural ophiolite belt. The massifs enclose chromite deposits. The ultrabasic rocks are characterized by high concentrations of refractory platinoids (PGE) of the Ru–Os–Ir composition and the subordinate role of Pt, Pd, and Rh. Laurite, erlichmanite, cuproiridsite, irarsite, ruarsite, hollingworthite, sperrylite, and other mineral phases are subordinate. Native gold, silver, copper, and iron are also found in these massifs. Recent detailed investigations of the Polar Urals have made it possible to discover a low-sulfide copper ore occurrence on the right bank of the Dzelyatyshor Creek (left tributary of the Malaya Kharamatalou River). We have detected for the first time gold and silver associated with palladium, bismuth, and tellurium in the copper ore.listelement.badge.dso-typeЭлемент, FORMATION SETTING OF EARLY MESOZOIC BASALTS OF THE RUSSIAN FAR EAST: ACCRETION OF THE PACIFIC GUYOTS OR EPICONTINENTAL RIFTING?(2007) Baskina V.A.; Tomson I.N.; Yakushev A.I.The formation setting and origin of alkali basalts hosted in Mesozoic siliceous–terrigenous rocks of the Russian Far East remain controversial issues. Some geologists believe that these basalts are remains of Pacific guyots in accreted oceanic terranes. Based on the presence of such basalts, the host fold-thrust structures are interpreted as open oceanic deposits transported over many hundreds of kilometers. Subsequently, they were adjoined to the continent as accretionary prisms in the Jurassic, Jurassic–Early Cretaceous, and Early Cretaceous. According to another concept, the Mesozoic alkali basalts are related to volcanism in the epicontinental basins (rift-grabens).listelement.badge.dso-typeЭлемент, NEW RESULTS OF MONITORING ACOUSTIC NOISE IN THE KOLA SUPERDEEP BOREHOLE(2007) Belyakov A.S.; Zhigalin A.D.; Lavrov V.S.; Lyubushin A.A.; Muhamedov V.A.; Nikolaev A.V.; Guberman D.M.; Yakovlev Y.N.Geophysical observations in the Kola superdeep borehole have been resumed after a prolonged interval. Previous geoacoustic investigations in this borehole were mainly casual and short-term. Moreover, the sensitivity and frequency range of the instrumentation applied were insufficient for registration of weak high-frequency acoustic vibrations.