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Том 32, 5, 2013 |
| I.A. Tararin, Z.G. Badredinov, V.M.
Chubarov. Geology and petrology of
metavolcanites of Kvakhonskaya suite of the Sredinnyi Range
crystalline massif, Kamchatka 3 N.S. Ostapenko, O.N. Neroda, P.P. Saphronov. Geological conditions, formation factors and ore mineralogical characteristics of the Pokrovka gold-silver deposit (Priamurye) 19 V.T. Kazachenko, A.I. Khanchuk, S.N. Lavrik, E.V. Perevoznikova. Phlogopite-olivine rocks of Taukha terrane (Southeastern Sikhote-Alin) 35 V.S. Pushkar, M.V. Cherepanova, O.Yu. Likhacheva. Detalization of the Pliocene-Quaternary North Pacific Diatom Zonal Scale 51 I.N.Ttikhonov, V.L. Lomtev. Shallow seismicity and tectonic features of the Sea of Japan 66 E.G. Ivolga, N.P. Romanovskii, V.G. Gurovich, Yu.F. Manilov. On the deep structure of the North Sikhote-Alin and North Sakhalin fold structures junction area 78 D.I. Tsarev, A.A. Batueva, S.V. Kanakin. Metosomatic transformation of diabase porphyrite dike 89 V.A. Lobkina, E.N. Kazakova, S.P. Zhiruev, N.A. Kazakov. Methods of landslide risk assessment for territory of settlements of Sakhalin Region (Makarov city, Sakhalin) 100 L.P. Demyanova, A.V. Melnikov, G.A. Yurgenson, A.M. Fodorov. Quartz raw materials from Baikal Lake to Amur River area and recommendations of the fluoride way for its processing 110 V.I. Roslikova. Special features of carbonate nodule genesis in meadow soils in Late Pleistocene noncalcareous deposits of the forest-steppe Prekhanka landscape 117 Jubilees Gorychev Nikolai А. (60th birth anniversary) 125 Malyshev Yuri F. (80th birth anniversary) 127 I.A. Tararin, Z.G. Badredinov, V.M. Chubarov Geology and petrology of metavolcanites of Kvakhonskaya suite of the Sredinnyi Range crystalline massif, Kamchatka Metavolcanites of Kvakhonskaya suite exposed on the western slopes of the Sredinnyi Range metamorphic massif are represented by two rock series. The lower series, occupying the most part of the suite exposures, is dominated by porphyric and aphyric clinopyroxene-plagioclase metabasalts and their tuffs with subordinate metapicrobasalts, metaandesites and their tuffs, and metadacites. The latter form isolated bodies in the northern part of the Kvakhonskaya suite. The upper series is composed of metaandesites, metabasalts, and their tuffs and intercalated terrigenous rocks (siltstones, carbonaceous greywackes) and metadacites bodies. The rocks are intensively metamorphosed under conditions of greenschist facies (t = 250°–420°C, Ps – about 1 кbar) with the replacement of clinopyroxene crystals (or their fragments in tuff varieties) by actinolite, chlorite, and epidote, and plagioclase crystals by albite, muscovite, chlorite, and epidote. The specificity of metamorphic alterations of the Kvakhonskaya suite volcanites is the development of Ca-Na and Na amphiboles (winchite, ferrowinchite, glaucophane, and ferroglaucophane) on clinopyroxene in the form of the thinnest streaks and finest grains (about 20–30 mkm). The groundmass (or cohesive tuff mass) consists of titanite, magnetite, chlorite, epidote, stilpnomelane, and albite, occurring in various combinations. Basite metavolcanites of the suite belong to high-iron and often high-titanium formations making them similar to tholeiitic basalts of MOR or rifting tholeiites. Metaandesites and metadacites also preserve a higher iron content and belong to typical rocks of calc-alkali series of the island arcs or active continental margins. Primary rocks of the Kvakhonskaya suite are supposed to have formed within isolated volcanic centres at the bottom of the vast Cretaceous epicontinental marginal basin where thick terrigenous rocks were deposited whose detrital material was supplied from the Northeastern Asian continent. Geological and geochemical data testify to the similarity of the Kvakhonskaya suite metavolcanites and the greenstone altered volcanites of the Pensantain Ridge of Western Kamchatka whose age is 90–100 Ma according to the data of the U-Pb SHRIMP zircon isotopy. The metavolcanite protolith of the Kvakhonskaya suite might have been formed in the same age interval within the Western Kamchatka island arc. Key words: metavolcanites, Kvakhonskaya suite, Sredinny Range metamorphic massif, geochemistry, paleotectonic reconstructions. N.S. Ostapenko, O.N. Neroda, P.P. Saphronov Geological conditions, formation factors and ore mineralogical characteristics of the Pokrovka gold-silver deposit (Priamurye) Pokrovka gold-silver deposit has been explored by boreholes. From the results of core testing, gently sloping ore bodies (deposits) have been revealed which are still being developed. They were thought to consist of quartz veins and vein and streak zones of the same occurrence. Examination of operating open-cast mines’ terraces allowed correcting existing concepts. It was shown that steeply dipping veins and vein-streak zones are dominant in their structure. In the central and western parts of the deposit they are north-eastward-directed< while in the eastern flank they are chiefly of the north-western orientation. The importance of different low-permeable for geological screens fluids is substantiated for localization and formation of ore bodies. The main factors of ore localization in screened hydrothermal systems have been established. The role of dacite sill thermal action in the formation of ore-enclosing cavities and mineral deposition is evaluated. Ore minerals spectrum including gold-bearing (copper gold and its compound intermetallids), earlier being unknown in the deposits, has been determined by electronic-microscopic ore studies. Based on the part played by all ore minerals micrometric sizes and their separation in quartz matrix, one can draw inference about non-equilibrium conditions of productive mineral deposition processes. Keywords: gold-ore deposit, occurrence and structure of ore bodies, ore localization factors, conditions for mineral deposition, ore minerals. V.T. Kazachenko, A.I. Khanchuk, S.N. Lavrik, E.V. Perevoznikova Phlogopite-olivine rocks of Taukha terrane (Southeastern Sikhote-Alin) Paleocene ultraferrum and Mn-rich phlogopite-olivine rocks of Taukha terrane belong to the alkaline ultrabasic rocks of a potassium series. Olivine is represented by hortonolite, and phlogopite is enriched in Cl. Phlogopite-olivine rocks contain titanomagnetite, Mn-rich ilmenite, Zn-rich pleionast, apatite, and zircon. Epigenetic serpentine, talc, carbonates, magnetite, breithauptite, niccolite, hedleyite, cobaltite, zumoite, auricupride, cuproauride, palladium gold, and other minerals are also found. Phlogopite-olivine rocks are probably a component part of the magmatic complex, earlier unknown in Sikhote-Alin, whose rocks are associated with fluodolites of a large diatreme. There is every reason to believe that they have resulted from the injection of magmatic material into the lithosphere upper layers. The magmatic material has a high portion of a fluid component whose main constituents were H2O, Cl, F, and S. From the specific features of formation, sharp predominant abundance of K over Na, and the enrichment by some incompatible elements (Sn, Ta, Nb, Zr), phlogopite-olivine rocks are more similar to lapmroite, but differ from them by high Fe, Mn, Au, Pt, Pd content and olivine composition. Manifestation of such magmatism in the Taukha terrane evidences that the subduction regime was changed into the transform margin one. Key words: phlogopite-olivine rocks, fluodolites, noble metals, Taukha terrane, Sikhote-Alin. V.S. Pushkar, M.V. Cherepanova, O.Yu. Likhacheva Detalization of the Pliocene-Quaternary North Pacific Diatom Zonal Scale A high-resolution diatom zonal scale has been developed on the basis of the stratigraphic diatom distribution in the Pliocene and Quaternary North Pacific deposits. The levels of the first evolutionary appearance and extinction of some diatom species are the base to establish zonal boundaries. Proposed diatom zones are traced in different facies of the North Pacific, mainly in the subarctic latitudes. The analysis of the diatom appearance and disappearance at the boundaries in the deposits of different biogeographic zones shows a space-temporal shift of these boundaries forced by the rates of the changes of paleopopulation densities and distribution areas during their expansion or degradation. This specification should be taken into account to provide the correlation between different biogeographical regions with specific features of the surface water masses. Key words: diatoms, biostratigraphy, Pliocene, Quaternary, anthropogene, North Pacific. I.N.Tikhonov,
V.L. Lomtev
Shallow seismicity and tectonic features of the Sea of Japan From the results of the data analysis from different seismic bulletins for the Japan Sea region the most comprehensive unified catalogue of earthquake with magnitude M 3.0 and depths h 60 km for the period 1975–2010 is prepared. Maps of epicenters of the events for four focus depth intervals (0–10, 11–20, 21–30 and 31–60 km) and three sublatitude sections 1° wide are plotted. Structural peculiarities and possible tectonic nature of the active seismic zone along the submarine margin or borderland of the Japan-Sakhalin island arc are examined; these are regional uplift, rather megaduplex fracture of compression faults, caused by crustal sliding at the rear of the frontal deep thrust. Crustal seismicity of the southeastern margin of the Korean peninsula (Sino-Korean shield) is most likely associated with the Tsushima and Ulleung faults. It is suggested that it might provoke the development of blocks, possibly tsunamigenic slides in the southern and eastern slide cirques of the Ulleung basin, cut into the Hwang Ho avandelta. Key words: shallow (crustal) seismicity, crustal tectonics, borderland, back upthrow, slide, Japan Sea, Japan-Sakhalin arc. E.G.
Ivolga, N.P. Romanovskii, V.G. Gurovich, Yu.F. Manilov
On the deep structure of the North Sikhote-Alin and North Sakhalin fold structures junction area The gravity field interpretation is performed for the North Sikhote-Alin and North Sakhalin structure junction area using the COSCAD-3D software package. Petrodensity and petromagnetic maps are compiled which allow obtaining the additional new data on pertophysical features and the deep structure of the study area. As a result of complex geophysical and petrophysical data interpretation, the sketch map of disjunctive tectonics of the region has been compiled and the ring structure has been distinguished featured by the singularity of petrodensity characteristics of the rock fill which is caused by the influence of the mantle deep structure. It can be considered as a magma chamber structure which center is located in North Sakhalin Bay. Key words: gravity field, petrodensity inhomogeneities, disjunctive disturbances, destruction of the lithosphere, magma chamber structure, Sikhote-Alin, Sakhalin. D.I. Tsarev, A.A. Batueva, S.V. Kanakin Metosomatic transformation of gabbro-porphyrite dike Endogenic clastic dykes and tubes are more often considered to be eruptive and explosive. It is supposed that while moving from the depth rock debris have been rounding taking the form of pebbles. It is hardly to imagine how under a short process, as an explosion, rock debris could be rounded and take the form of pebbles. Some geologists consider that explosive pebble dykes and tubes have been formed as a result of fluid turbulence in the earth’s crustal cavities. At the same time, fragments of the mountain rocks elevated, rolled and rounded. rounding rock debris in the cavities of the earth’s crust under fluidization. In any case rounding rock debris is a mechanical process. This work is an evidence of an example of isotropic dyke clasts formation by a tectono-metasomatic way. Keywords: fragmental metasomatism, fluidization, solubility, infiltration and diffusive emplacement, Eastern Sayan. V.A. Lobkina, E.N. Kazakova, S.P. Zhiruev, N.A. Kazakov Methods of landslide risk assessment for territory of settlements of Sakhalin Region (Makarov city, Sakhalin) The main damage inflicted by landslides on the population and economy of Sakhalin Region is manifested in infrastructure and buildings damage and destruction and blocking of roads, lines of communications and electric transmission by landslide deposits. Also some victims of the landslides have been registered. High landslide danger requires creating schemes of planning limitation for the territories of settlements of Sakhalin Region while elaborating the documents for territorial planning (general plans). The authors suggest the methods of landslide risk assessment for construction of schemes of planning limitation for the settlement territories. The methods offered are useful for landslide risk assessment of an extended territory (for example, the territory of a settlement), because they help to visualize information in terms of landslides location on large-scale maps, to evaluate an area affected by landslide processes, and to obtain information about objects and buildings (type and quantity of buildings and their location as to the landslide massif) in a landslide dangerous zone, etc. Also it enables to determine the degree of a landslide danger. In accordance with the category of the landslide danger for each area, it becomes possible to take precautionary measures on the engineering protection danger or to move objects from the dangerous zone. The methods of landslide risk assessment are illustrated by way of example of the city of Makarov (the eastern coast of Sakhalin Island). Key words: landslide, landslide danger, Sakhalin Region, scheme of planning limitation. L.P. Demyanova, A.V. Melnikov, G.A. Yurgenson, A.M. Fedorov Quartz raw materials of the Baikal-Amur region and suggestions for their processing by fluoride method The paper presents the results of the examinations of silica-bearing raw materials deposits. They are located in the territories of the Irkutsk, Amur regions and Transbaikalie, the Baikal-Amur Region, displaying balance resources and prospective reserves. As a result of the examination of integrated processing the silica-bearing raw materials, a technique for processing by fluoride method has been devised. Widening the scope of raw material base of the silica industry of the Russian Federation along with the study of the processing of silica-bearing raw material of various composition make a contribution to the solution of many targets with the use of pure amorphous silica. Key words: silica-bearing raw material, quartzites, integrated processing, ammonium hexafluosilicate, amorphous silica, Baikal-Amur Region. V.I. Roslikova Special features of carbonate nodule genesis in meadow soils in Late Pleistocene noncalcareous deposits of the forest-steppe Prekhanka landscape The paper presents new materials revealing genetic features of the formation of carbonate nodules in meadow soils of the superaqueous landscapes of the Prekhanka lowland on heavy clay Loam, clayey noncalcareous sediments. Key words: superaqueous landscapes, soil, carbonate nodules, micromorphology, paleogeographic environment, Prekhanka Lowland, Far East of Russia. |