Contents
Volume 18, ¹ 1, 1999
ContentsVolume 18, ¹ 1, 1999 |
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Stratigraphy
A.G.Konstantinov, Ye.S.Sobolev. Biostratigraphic scheme for the Carnian and Lower Norian of northeast Russia. Article 1. Description of sections, and stratigraphic range of cephalopods 3
A.G.Klets, S.G.Kislyakov. Regional stratigraphic units of the Carboniferous, northern Khabarovsk Territory 18
A.M.Korotky, N.G.Razjigaeva, T.A.Grebennikova, L.A.Ganzey, L.M.Mokhova, V.B.Bazarova, L.D.Sulerzhitsky, K.A.Lutaenko. Holocene deposits and paleogeography of Kunashir Island, Kurile Islands 25
Mineralogy and Geochemistry
N.V.Astakhova, A.V.Sorochinskaya. Authigenic carbonates in the Upper Pleistocene – Holocene deposits of marginal seas, northwest Pacific 41
V.I.Gvozdev, A.V.Ignatiev, V.V.Ratkin, T.A.Velivetskaya, N.G.Ukhaneva.
d18O and d13C isotope composition of carbonates in Vostok-2 deposit (Primorie) 50A.V.Mozherovsky, Ye.P.Terekhov.Authigenic minerals from cement of Early Cretaceous and Paleocene sedimentary rocks of the Yamato rise (Sea of Japan) 59
Metallogeny
V.I.Goncharov, A.A.Sidorov. Rejuvenation of deposits of volcanogenic belts 70
I.Yu.Gromakovsky, V.A.Stepanov. Gold mineralization in carbonate thick units of Oktyabrsky region, Priamurie 84
M.V.Goroshko, V.A.Guryanov, V.Ye.Kirillov. Uranium metallogeny of the south-eastern part of the Siberian platform 90
A.A. Gavrilov. Mineragenic asymmetry and dissymetry of central type structures (CTS). Article 1. The Curie principle and metal ore and diamon-bearing kimberlite distribution in hearth systems. 103
Brief Communications
L.B.Khershberg, M.M.Zadornov, M.M.Yurinets, V.A.Polinovsky, E.L.Shkolnik, O.V.Chudaev, I.N.Govorov. Comparative results of sea floor drilling and dredging data from the Western Pacifiñ 115
Anniversaries
Vadim V.Onikhimovsky (in commemotation of the 85th birth anniversary) 118
Valery B.Troyan ( (in commemotation of the 60th birth anniversary)
A.G.Konstantinov, Ye.S.Sobolev
Biostratigraphic scheme for the Carnian and Lower Norian of northeast Russia.
Article 1. Description of sections, and stratigraphic range of cephalopods.The main sections of the Carnian and Lower Norian of Northern Priokhotie, Omolon massif, Adycha River Basin and Kharaulakh Range are described by layers. The stratigraphic range of ammonoids, nautiloids and coleoids is analyzed, and assemblages of the species are distinguished and traced on the study territory. Twelve ammonoid and six nautiloid assemblages are recognized in the Carnian and Lower Norian of northeast Russia. These data are the basis for improving and detailing the biostratigraphic scheme of the Boreal Upper Triassic.
A.G.Klets, S.G.Kislyakov A.G.Klets, S.G.Kislyakov
Regional stratigraphic units of the Carboniferous, northern Khabarovsk Territory
A successive change of faunal assemblages has been ascertained in the sections of Carboniferous deposits of the southern part of the Verkhoyano-Kolyma fold system and Okhotsk massif. On the basis of the distinguished layers with fauna the sections were correlated with each other and with the section of adjacent regions, and a biostratigraphic characteristics was given to regional and local stratigraphic units.
A.M.Korotky, N.G.Razjigaeva, T.A.Grebennikova, L.A.Ganzey, L.M.Mokhova, V.B.Bazarova, L.D.Sulerzhitsky, K.A.Lutaenko
Holocene deposits and paleogeography of Kunashir Island (Kurile Islands)
Natural environment development and sedimentary environment evolution were studied for Kunashir Island in the Middle-Late Holocene. Against the background of global climatic changes natural environment dynamics was influenced by migration of the warm and cold current system. Dry and cool climate was changed by warm and moist climate about 7-6.5 ka, somewhat later than on Hokkaido Island. At that time the Kuroshio Current became more active, and Kunashir Island vegetation changed greatly: birch associations were replaced by nemoral broad-leaved forests. During Atlantic-Subboreal cooling (4.5-4.7 ka) the island's vegetation changed slightly, which was due to a warm current influence. The most considerable regression for the Middle-Late Holocene took place in this period. That cooling of about 3.5-3 ka led to strong vegetation changes: coniferous and broad-leaved/coniferous forests developed. Active detrital material arrival at the coastal zone resulted in the growing of accumulative landforms. During Subboreal-Subatlantic cooling (1.8-1.3 ka) the isthmus area grew in size, coastal wetlands with lakes and coastal dunes were formed; meadow and swamp landscapes developed. Subatlantic warming was not intensive. Active eolian accumulation took place during the Little Glacial Period of cooling and regression.
N.V.Astakhova, A.V.Sorochinskaya
Authigenic carbonates in the Upper Pleistocene – Holocene deposits of marginal seas, northwest Pacific
The paper presents data on authigenic carbonate distribution in the Holocene - Upper Pleistocene deposits of the Okhotsk, Japan, East China, Philippine and South China Seas. Description of the carbonates, chemical and isotope composition of the samples are given. The chemical analysis of the samples indicates that almost all authigenic carbonates are composed of calcite or magnesian calcite; and only in one case, of siderite. Isotope oxygen composition ranges from +37.7 to +26.1‰ (SMOW); it is, probably, connected with different temperatures of carbonate formation. A distinct geographic regularity is traced. A decrease in d18O values is observed from the cold Okhotsk Sea to the warm South China Sea. A very wide range of the isotope carbon composition, from -42 to +3.8‰, indicates different sources of carbonic acid required for these carbonates formation. As a basis for isotope carbon composition we can distinguish three sources of carbonic acid in the studied sediments: microbiological methane oxidation, organic matter destruction during sediment diagenesis and dissolved organogenic limestone. Thus, the formation of authigenic carbonates in sediments of the marginal seas of the Northwest Pacific is the result of: 1) sediment diagenesis, 2) methane oxidation in the zones of gas anomalies, 3) their precipitation from the supersaturated by carbonates sea shoal waters of the tropical sea lagoons.
V.I.Gvozdev, A.V.Ignatiev, V.V.Ratkin, T.A.Velivetskaya, N.G.Ukhaneva
d18C and d13C isotope composition of carbonates in Vostok-2 deposit (Primorie)
For the first time the authors discuss the results of study of d13C and d18O in carbonates from limestones, marbles, skarns, ores, and post-ore veinlets in the skarn-scheelite -sulfide deposit Vostok-2 in Primorie. It has been established that the d13C and d18O values obtained for limestones (from 2.8 to 3.6‰ and from 21.1 to 23.8‰, respectively) testify to their sea genesis. Close values of d13C and d18O (from 2.4 to 3.1‰ and from 22.0 to 24.1‰, respectively) are characteristic of marbles found in the contact of granitoid masses and stocks and indicate a subordinate role of hydrothermal fluid in the process of contact metamorphism. More significant variations of isotopic composition of these elements have been established for the rocks altered through skarnization process. For example, marbles in the contact with skarns show d13C from 1.9 to -0.5‰ and d18O from 19.0 to 15.0‰, which may indicate an increasing role of the deep hydrothermal fluid at that time. Calcites found among skarns and ore minerals and calcites from post-ore veinlets have d13C from -0.5 to -13.0‰ and d18O from 17.0 to -3.0‰
A.V.Mozherovsky, Ye.P.Terekhov
Authigenic minerals from cement of Early Cretaceous and Paleocene sedimentary rocks of the Yamato rise (Sea of Japan)
Authigenic minerals from cement are good indicators of sedimentation environment and processes of sediment transformation from the beginning of their burial to the deepest levels of metamorphism. Yet they have not been studied in marginal seas, and their investigation can considerably amplify knowledge of the history of sedimentation and extend some general problems of development of the Sea of Japan region.
V.I.Goncharov, A.A.Sidorov
Rejuvenation of deposits of volcanogenic belts
Under analysis are the peculiarities of discrete formation of complete and incomplete series deposits of ore assemblages of volcanogeic belts as exemplified by the Russian Northeast. The complete series include deposits different by their temperature characteristics, low-temperature deposits inclusive. The incomplete series do not comprise the latter group. The deposits of complete ore-formation series were generally developing according to the stage-by-stage, monophase scheme of ore genesis without any considerable rise in temperature by the beginning of every new phase of their formation under conditions of gradual cooling of mineral-forming environments. The formation of incomplete-series deposits was also of stage-by-stage but polyphase character and occurred in the conditions of rejuvenation of mineralization with a sharp increase in temperature by the beginning of the next phase, stage, with a discontinuity in crystallization and appearance of a specific high-temperature mineral complex. An appreciable temperature rise of hydrotherms was due to repeated tectono-magmatic activation of the ore region.
I.Yu.Gromakovsky, V.A.Stepanov
Gold mineralization in carbonate thick units of Oktyabrsky region, Priamurie
As exemplified by ore occurrences of Jeltulak, types of gold mineralization in cabonate units of Priamurie were studied. A comparative geochemical and petrochemical analysis was done of the ores and enclosing carbonate rocks of the examined ore shows and Carlin gold deposit, Nevada, USA. A tendency to mineralized dolomites enrichment in argillaceous-hydromica components (K, Al) and ore elements was established. The ore bodies are represented by banded or brecciated dolomites with vein gold-polymetallic, lenticular gold-magnetite-pyrrhotite and impregnated gold-pyrite-arsenopyrite mineralization. They occupy a certain stratigraphic position in the section of the carbonate unit. The ores are characterized by free, high purity gold of various classes of grain size in association with cinnabar. Gold-pyrite-arsenopyrite mineralization of the Jeltulak ore show is similar to the ores of Carlin type deposits, particularly to carbonate ores of the Vorontsov deposit in the Urals. The prospects for revealing gold mineralization in carbonate units of Priamurie are outlined.
M.V.Goroshko, V.A.Guryanov, V.Ye.Kirillov
Uranium metallogeny of the south-eastern part of the Siberian platform
The paper considers new data on uranium metallogeny of the south-eastern part of the Siberian platform. It is shown that uranium occurrences are widespread in the hydrothermal altered rocks of the region. They are represented by different genetic types and formed in the periods of tectonic and magmatic activation of regional structures in the Proterozoic, Riphean and Mesozoic. There are cases of uranium accumulation in Neogene-Quaternary crusts of weathering. The Riphean eisitic, beresitic, argillized formations and Mesozoic argillisites are most productive for ore genesis.
A.A. Gavrilov
Mineragenic asymmetry and dissymetry of central type structures (CTS).
Article 1. The Curie principle and metal ore and diamon-bearing kimberlite distribution in hearth systems.
Åndogenic structures of central type( SCT) represent a class of injective dislocations of crust and mantle location, which control distribution of shows, deposits and concentration areas of mineral resources of different types (metals ores, diamonds, hydrocarbons,etc.). A comparative study and revealing of common regularities of CTS localization of different genesis age and range are necessary for the use of their description and characters to be formalized. One of the most effective ways of solving these problems is applying a theory of symmetry. There are numerous examples of hearth structures of different orders characterized by asymmetric location of metal ores and diamond-bearing kimberlites with respect to the geometric centre and the mirror line, by different productivity and specialization of diametrically located blocks. The basis for this phenomenon is the mutual superposition of symmetries of structure-forming energy-mass transportation flows and anisotropic geologic environment (Curie principle). The mineragenic asymmetry of CTS is rather widespread, which is necessary to take into account when conducting prospecting and making different-scale predictions.
L.B.Khershberg, M.M.Zadornov, M.M.Yurinets, V.A.Polinovsky, E.L.Shkolnik, O.V.Chudaev, I.N.Govorov
Comparative results of sea floor drilling and dredging data from the Western Pacific
The paper describes the first experience of using original drilling equipment for estimation of manganese crust resources in the Western Pacific. A comparison of the dredging and drilling data shows that the drilling method always decreases the thickness of the crusts.