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First data on the geologic and geochemical compositions of kimberlites from nine kimberlite pipes of southwestern Angola are presented. In the north of the study area, there are the Chikolongo and Chicuatite kimberlite pipes; in the south, a bunch of four Galange pipes (I-IV); and in the central part, the Ochinjau, Palue, and Viniaty pipes. By geochemical parameters, these rocks are referred to as classical kimberlites: They bear mantle inclusions of ultrabasites, eclogites, various barophilic minerals (including ones of diamond facies), and diamonds. The kimberlite pipes are composed of petrographically diverse rocks: tuffstones, tuff breccias, kimberlite breccias, autolithic kimberlite breccias, and massive porphyritic kimberlites. In mineralogical, petrographic, and geochemical compositions the studied kimberlites are most similar to group I kimberlites of South Africa and Fe-Ti-kimberlites of the Arkhangel'sk diamondiferous province. Comparison of the mineralogical compositions of kimberlites from southwestern Angola showed that the portion of mantle (including diamondiferous) material of depth facies in kimberlite pipes regularly increases in the S-N direction. The northern diamond-bearing kimberlite pipes are localized in large destructive zones of NE strike, and the central and southern diamond-free pipes, in faults of N-S strike.

On the basis of combined (paleomagnetic, lithological, and paleontological) data, a scale of Neogene geomagnetic polarity is proposed for the West Siberian Plate (WSP). It comprises 17 large orthozones of normal and reversed polarity. The scale was compiled by comparing and correlating the Neogene key sections of the Kulunda and Baraba plains, Irtysh regions between Omsk and Pavlodar and near Tara, and Ob' region near Tomsk. The reliability of paleomagnetic data is confirmed by component analysis of natural remanent magnetization and by a possibility of determining its primary component. In the studied Neogene rocks this is a high-temperature component related to magnetite, hematite, and maghemite, which decays at 420-675

The Ogurtsovo section, one of the key sections of the Ob' region near Novosibirsk, has been comprehensively studied using a detailed geological description of deposits, granulometric and petromagnetic analyses. The combined methods allowed us not only to interpret the geologic structure of the Ogurtsovo section in terms of its facies and genesis but also to refine and supplement the Pleistocene geologic history of the region. Emphasis was placed upon relationships between granulometric and petromagnetic parameters. As a result, we have revealed regularities in the behavior of magnetic characteristics and their relationships as a function of granulometry in different lithogenetic types of deposits. On the example of this key section, criteria are proposed for distinguishing facies of the subaerial complex by analytical methods.

We report results of an integrated study of volcanosedimentary rocks of the Middle-Late Miocene Dzhilinda Formation consisting of the prevolcanic sedimentary Lower Dzhilinda and volcanosedimentary Upper Dzhilinda subformations. The section was studied in three wells drilled near Lake Mukhal (Khoigot paleovalley, Vitim upland). The Dzhilinda sediments contain ubiquitous Alveolophora jouseana (Moiss.) Moiss. typical of Miocene environments. Deposition occurred in two main stages represented by different water (diatoms) and land (spores and pollen) plant communities. The upsection successive changes in diatom species are attendant with changes in pollen and spore assemblages. The K-Ar ages of lavas indicate that the mostly sedimentary lower section of the Dzhilinda Formation deposited between 12 and 14 Ma and the more volcanic upper section, with a lacustrine lens at base, formed at about 10.8-9.5 Ma. The isotope dating of volcanic rocks agrees with the ages inferred from the diatom and spore-pollen analyses. The prevolcanic Lower Dzhilinda subformation deposited during the Middle Miocene climate optimum. The stratigraphy, lithology and facies of sediments suggest that the Dzhilinda deposition was associated with the development of a deep freshwater lake in the conditions of active tectonism and volcanism.

We report results of bottom temperature monitoring of 2003-2004 in the deepwater South Baikal basin (Lake Baikal) near active gas-fluid methane vents at lake depths of 1020 and 1350 m. Sediments and water temperatures were measured using an autonomous temperature recorder designed at the Institute of Geophysics (Novosibirsk). Experiments implied short-duration recording and pioneering continuous 350 day-long monitoring near the Staryi vent. Measurements within a 1 m thick layer above and below the bottom showed notable variations in water (up to 0.07

The Central System (CS) or Spanish Central System forms part of two of the five morphotectonic mesoblocks that make up the Intermediate macroblock (number 6) of the Iberian plate. The combination of geological, geophysical and geomorphological data, used in accordance with the Rantsman methodology (1979), served as the basis for obtaining a regional analysis. The cartography obtained shows territorial units (4 macroblocks, 4 mesoblocks, 35 blocks, 85 microblocks and 162 nanoblocks), morphotectonic alignments (quantity/order: 3/2, 4/3, 5/23, 6/48, 7/93 and 8/164) and morphotectonic knots (quantity/order: 1/2, 5/3, 35/4, 85/5, 162/6, 324/7, 816/8). The number of delimited morphostructures increases from the central part towards the east. At the block level, one may distinguish a transverse differentiation of the territorial units and alignments, which is interpreted as an expression of the region's lithospheric heterogeneity. There is a close relationship between the morphostructures and seismicity, indicating that greater activity occurs in the blocks of the eastern and northeastern sectors.

Complex study and comparative analysis were carried out for two gold deposits, Vodorazdel'noe and Ondol'toi, localized among carbonate and siliceous-carbonate rocks of the Il'chir Formation in southeastern East Sayan. The Vodorazdel'noe deposit is of gold-quartz-sulfide type; it formed at 275-300

Spinel-anthophyllite rocks that may be classified as ultrabasic low-Ca spinel amphibolites have been first discovered in the Kokchetav collision zone (northern Kazakhstan). They outcrop 2 km west of Enbek-Berlyk Village among schists and quartzites and are closely associated with spinel harzburgites and garnet pyroxenites. The main hosted minerals are spinel (hercynite) and anthophyllite. The rocks bear magnetite-hornblende-spinel-anthophyllite pseudomorphs with rounded and polygonal sections, which might have been resulted from the replacement of garnet grains. The prismatic anthophyllite crystals and scarce olivine relics contain elongate parallel spinel inclusions resembling spinel-olivine syntactic intergrowths in the Enbek-Berlyk spinel harzburgites. The spinel-anthophyllite rocks are similar to the associated spinel harzburgites in CaO, MnO, SiO₂, and Al₂O₃ contents but are richer in FeO and poorer in MgO ( F = FeO/(FeO + MgO) = 57% against 35% in the harzburgites). Geological, mineralogical, and geochemical data suggest that the spinel-anthophyllite rocks formed during the isochemical contact metamorphism of garnet-bearing spinel harzburgites, which contained more FeO and less MgO than garnet-free harzburgites of the same area. Variations in FeO and MgO contents in both types of harzburgites seem to be due to different chemical compositions of the chlorite protoliths of these rocks.

The relief of a vast area of western China and southern Mongolia was analyzed by methods of specialized morphometry to reveal structural and morphological features of recent tectonism. The tectonic relief of some part of the collisional system of Inner Asia, including the eastern Tien Shan, Govi Altay, and Bei Shan, is characterized by a general decrease in heights from west to east and a complicated system of domal ridges and intermontane troughs controlled by lenticular-rhombic faulting in the upper lithosphere. Submeridional transverse linear lows play an important role in the structure of the tectonic relief. It is likely that they are due to an irregular longitudinal flow of lithosphere blocks in the process of submeridional transverse compression. The structural signature of collisional geodynamics is traced eastward to the Ordos Province in a large meander of the Huang He and northward to the Hangayn Mountains, Tuva, and southern Gorny Altai. The predominance of domal deformations in young uplifts and no signs of their block desintegration suggest a crucial role of vertical tectonic motions largely responsible for the recent tectonic style of the eastern Tien Shan and Altay.

The Bohai Gulf basin is the largest petroliferous basin in China. Its Carboniferous-Permian deposits are thick (on the average, ca. 600 m) and occur as deeply as 5000 m. Coal and carbonaceous shale of the Carboniferous Taiyuan Formation formed in inshore plain swamps. Their main hydrocarbon-generating macerals are fluorescent vitrinite, exinite, alginite, etc. Coal and carbonaceous shale of the Permian Shanxi Formation were deposited in delta-alluvial plain. Their main hydrocarbon-generating macerals are vitrinite, exinite, etc. The carbonaceous rocks of these formations are characterized by a high thermal maturity, with the vitrinite reflectance R⁰ > 2.0%. The Bohai Gulf basin has been poorly explored so far, but it is highly promising for natural gas.