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On the basis of complex research into the western part of the West Siberian Plate, a new scheme of the structure-formation zones of its basement has been developed and a new geological map of its pre-Jurassic basement has been compiled. Ophiolites and other mafic-ultramafic complexes (fragments of the oceanic Earth’s crust) were studied. The most complete Late Ordovician ophiolite complex comprising a melange of serpentinites, gabbroids, plagiogranites, and basalt with jasper interbeds lies in the Shaim area. Weakly altered spinel lherzolites were also examined there. The research has revealed not only Ordovician but also Devonian basalts as well as gabbroid complexes (392 Ma, Sm-Nd dating). The Paleozoic geodynamic history of the region was terminated with collision, which was accompanied by tectonic piling and the intrusion of granite plutons, metamorphism, and formation of new continental crust. These crucial events, which consolidated Paleozoic complexes throughout the vast area of the future West Siberian megabasin, date from the Early Permian. The composition, age, and nature of granitoid plutons in western West Siberia were studied, and isochrons and isotope characteristics were obtained, which give an insight into both the genesis and age of granite plutons and their subsequent transformations.

The substance composition, properties, and areas for use of five large scale varieties of technogenic high-alumina mineral raw materials are considered: aluminothermal slags, organic synthesis catalysts, abrasive slurries, aluminium slags and alumina dust. With combined use on the basis of this secondary raw material it is possible to produce more than twenty forms of different product:Currently in the Ural region a number of scientific organizations and industrial enterprises are participating in the fulfilment of Regional and Federal programs for processing technogenic formations. In 2008 the presidium of the Russian Academy of Sciences developed and approved a comprehensive program for study and assimilation of untraditional sources of mineral raw material, including technogenic formations. Main attention in the academic program is devoted to high-alumina natural and technogenic raw material sources: minerals of the kyanite, andalusite, silimanite, kaolinite and pyrophilite groups, aluminosilicate waste from thermal power engineering, high-alumina slags, slurries, dust, etc. Within the scope of fulfilling these programs there is research work, a study of substance composition and properties of mineral raw materials, and promising areas are being developed for use of the most valuable varieties of technogenic high-alumina materials. Among the latter are the following large-scale technogenic formations are of greatest practical interest (limits of Al 2 O 3 content, wt.%, are shown in brackets): aluminothermal slags in the production of the majority of ferroalloys and master alloys (50 -85), wastes of catalyst production or synthetic rubber (65 -75), corundum slurry from abrasive production (82 -96), dust from alumina calcining furnaces (90 -97), and metal-mineral waste from the production of secondary aluminum (60 -72).Technogenic "deposits" are primarily a potential raw material for synthesis of refractories, heat-resistant, and ceramic fuzed materials of different composition: alloyed corundum, mullite-corundum, spinel, codierite, etc. In view of the wide range of mechanical, thermal and chemical properties many varieties of technogenic mineral raw materials may be used effectively, not only in the refractory branch, but also in the production of abrasives, binders, heat insulation and other functional materials and objects [1 -3]. In order to develop effect areas for recycling secondary mineral resources complete information si necessary about the substance, grain size composition and physicochemical properties of each variety of technogenic polyphase and often polydispersed technogenic raw material. ALUMINOTHERMAL SLAGS FROM FERROALLOY AND MASTER ALLOY PRODUCTIONOAO Klyuchev Ferroalloy Plant is the sole enterprise in the RF and CIS producing more than thirty named unique ferroalloys and master alloys by the method of aluminothermal reduction of metals from oxides and other com-. 3 OOO Klyuchev Enrichment Plant, Dvurechensk, Sverdlovsk Region, Russia. 4 OAO UK RosStetsSplav, Yekaterinburg, Russia. 5 OOO NPO V...

Ultramafic magmas made the main contribution to PGE mineralization of ophiolite associations. An orebearing dunite-chromitite complex intruded from the mantle depth is widespread in the southern Kempirsai massif, where a large chromite deposit of Os-Ir specialization has been formed. The PGE contents (mg/t) in this type of chromitites (290 Os, 265 Ir, 200 Ru, 60 Pt, 55 Pd,18 Rh) reflect the specific character of Cr-bearing melt as an efficient carrier of PGE, while host dunite is practically free of PGE (about 20 mg/t in total). The geochemical specialization of ophiolite chromitites is displayed only for refractory PGE (Os, Ir, Ru), prevailing over fusible PGE (Rh, Pd, Pt). Therefore, the ophiolite association was classified as chromite-bearing and unpromising for PGE mineralization, as was exemplified in the Urals by Zavaritsky and Betekhtin, who opposed this rock association to PGE-bearing zonal and layered intrusions. This difference is caused by reductive conditions and high PT parameters dominating in magmatic chambers of ophiolite associations. The main conclusion that can be drawn from this study Abstract -On the basis of a representative collection of ultramafic rocks and chromite ores and a series of technological samples from the largest (Central and Western) deposits in the Rai-Iz massif of the Polar Urals and the Almaz-Zhemchuzhina and Poiskovy deposits in the Kempirsai massif of the southern Urals, the distribution and speciation of platinum-group elements (PGE) in various type sections of mafic-ultramafic massifs of the Main ophiolite belt of the Urals have been studied. Spectral-chemical and spectrophotometric analyses were carried out to estimate PGE in 700 samples of ultramafic rocks and chromite ores; 400 analyses of minerals from rocks, ores, and concentrates and 100 analyses of PGE minerals (PGM) in chromite ores and concentrates were performed using an electron microprobe. Near-chondritic and nonchondritic PGE patterns in chromitebearing sections have been identified. PGE mineralization has been established to occur in chromite ore from all parts of the mafic-ultramafic massifs in the Main ophiolite belt of the Urals. The PGE deposits and occurrences discovered therein are attributed to four types (Kraka, Kempirsai, Nurali-Upper Neiva, and Shandasha), which are different in mode of geological occurrence, geochemical specialization, and placer-forming capability. Fluid-bearing minerals of the pargasite-edenite series have been identified for the first time in the matrix of chromite ore of the Kempirsai massif (the Almaz-Zhemchuzhina deposit) and Voikar-Syn'ya massif (the Kershor deposit). The PGE grade in various types of chromite ore ranges from 0.1-0.2 to 1-2 g/t or higher. According to technological sampling, the average PGE grade in the largest deposits of the southeastern ore field of the Kempirsai massif is 0.5-0.7 g/t. Due to the occurrence of most PGE as PGM 10-100 mm in size and the proved feasibility of their recovery into nickel alloys, chromites of the Kempirsai massif can be con...