Volume 21, 4, 2002
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Volume 21, 4, 2002 |
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A.G. Rodnikov, N.A. Sergeyeva, L.P. Zabarinskaya. The deep structure of the Deryugin basin (Sea of Okhotsk) 3
A.M. Petrishchevskiy. Structural wedges in the earth's crust of the Russian Far East margin (geophysical features) 9
Liu Zhaojun, Wang Simin. Mesozoic sequence stratigraphic framework features and its genetic analysis of Songliao Basin, Northeast China 18
Kwang-Soo Seo, Dong-Woo Lee, In-Chang Lyu, Byung-Su Lee. Conodonts from the Dumugol formation Lower Ordovician, Tanyang area, Korea 26
V.P. Tuzov, L.I. Mitrofanova, R.V. Danchenko, V.P. Boldyreva. The Kurasiysk-Maruyam complex of Neogene deposits in South Sakhalin 37
V.G. Pyatiletov. The problem of the age of the Tukuringra complex in the Mongol-Okhotsk fold area 48
I.V. Buchko, A.E. Izokh, M.Yu. Nosyrev. Sulfide mineralization of ultrabasite-basites of the Stanovoy megablock in the southern framing of the North Asian craton 56
V.A. Stepanov, A.V. Melnikov, V.I. Palazhchenko, T.V. Makeyeva, V.I. Gvozdev. Original sources of platinum metal placer shows of the Dambuki cluster in the Upper Priamurye region 69
A.B.Osipenko, Ye.G.Sidorov, A.P.Kozlov, E.A.Landa, G.V.Ledneva, B.A.Markovskiy. Geochemistry of magmatic series from the Galmoenanskiy mafic-ultramafic massif, Koryakia 79
V.O. Khudolozhkin, O.V. Avchenko. Investigation of the forms of existence of dissolved particles in the water-silica system in subcritical and supercritical conditions by the method of thermodynamic modeling 92
N.V. Boldovskiy. The structural and geological conditions of formation and distribution of underground waters in the East Asian volcanic belt 103
Obituary
F.G. Korchagin (1946-2002) 122
A.G. Rodnikov, N.A. Sergeyeva, L.P. Zabarinskaya
The deep structure of the Deryugin basin (Sea of Okhotsk)
The Deryugin basin is a unique structure located in the Sea of Okhotsk. The sediment thickness reaches 12 km. The basin is characterized by increased values of the heat flow, thin crust, and seismic and hydrothermal activity. The basin is located above a hot plume in the mantle, i.e. an asthenospheric diapir detected in the upper mantle at a depth of 20-25 km. The western slope is bounded by an ophiolite belt of ultrabasic magmatic rocks, which apparently determines an ancient (Mesozoic) subduction zone separating the Deryugin basin from Eastern Sakhalin and at the same time representing an island arc with andesite magmatism. Behind the arc, there was a back-arc sedimentary trough which was filled with volcanic siliceous and clayey siliceous sediments in the Cretaceous and which now forms the folded basement of Northern Sakhalin. In this context the assumption is substantiated of good prospects for oil and gas of the sedimentary basins Mesozoic base formed for the major part in the conditions of back-arc basins favorable for generation, accumulation and conservation of hydrocarbons.
A.M. Petrishchevskiy
Structural wedges in the earth's crust of the Russian Far East margin (geophysical features)
The typical seismic and gravity crust models of epicontinental areas (Sikhote-Alin, Kamchatka, the ?urils, and southwestern Australia) are analyzed. The feature of these regions is the structural wedges intruded under the epicontinental geological structures at the "crust-mantle" boundary. Wave-velosity and density of the wedge-shaped layers in the lower part of the crust decrease, and the same parameters increased in the subsurface layers from ocean to continent. The geometrical and material descriptions of the structural wedges in the lower part of the crust are combined with the tectonic nappes and accretionary complexes on the surface. The origin and tectonic evolution of the structural wedges is related to the crust and upper mante splitting during the collision of lithosphere plates.
Liu Zhaojun, Wang Simin
Mesozoic sequence stratigraphic framework features and its genetic analysis of Songliao Basin, Northeast China
A hierarchy of sequence stratigraphic subdivisions is suggested for the Late Jurassic - Cretaceous deposits of the Songliao basin based on the results of seismic survey and also holes and outcrops. A megasequence, supersequence set, supersequences, sequences and parasequences are distinguished characterizing stages of the basin development and different-order cyclic recurrence. Regional and global factors are considered that govern the course of the basin evolution.
Kwang-Soo Seo, Dong-Woo Lee, In-Chang Lyu, Byung-Su Lee
Conodonts from the Dumugol formation Lower Ordovician, Tanyang area, Korea
This study is to clarify the geologic time of the Dumugol Formation in the Tanyang area on the basis of conodonts. A total of 245 identifiable conodonts were recovered from 56 samples. They are classified into 7 multielement species referable to 10 genera, and 9 form species belonging to 13 genera. In terms of biostratigraphic biozones, the Dumugol Formation is divided into four conodont zones, viz, Chosonodina herfurthi - Rossodus manitouensis, Glyptoconus quadraplicatus, Paracordylodus gracilis, and Triangulodus dumugolensis zones in ascending order. Conodont fauna of the Dumugol Formation is correlated with the Chosonodina herfurthi - Rossodus manitouensis zone to the Triangulodus dumugolensis zone of the Dumugol Formation in the Baegunsan Syncline region, the Cordylodus rotundatus - Acodus oneotensis zone to the Scalpellodus tersus zone of North China, Fauna C to Fauna E of North America, the Cordylodus rotundatus zone to the Oepikodus evae zone of the Baltic region, the Chosonodina herfurthi - Acodus zone to the Drepanodus gracilis - Scolopodus sexplicatus zone in Australia.
The Dumugol Formation is Late Tremadocian through Early Arenigian of Europe, Late Ibexian through Early Canadian of North America in age.
Most of the recovered conodonts are well preserved and are brownish black (5YR 2.5/1 to 2.5 YR 2.5/1 by Munsell Soil Color), displaying a color alteration index of 4-5 and indicating that these rocks have been heated to 300-400 degrees Celsius.
V.P. Tuzov, L.I. Mitrofanova, R.V. Danchenko, V.P. Boldyreva
The Kurasiysk-Maruyam complex of Neogene deposits in South Sakhalin
The Maruyam deposits in the south of Sakhalin Island are of great interest with respect to their gas potential. At present there is no one single point of view concerning the boundaries and the volume of the Maruyam suite. This paper offers the biostratigraphic characteristics of reference sections of the Kurasiysk and Maruyam suites. Diatom flora in the examined deposits makes it possible to accomplish correlation with the general geochronological chart and to give grounds for their age.
V.G. Pyatiletov
The problem of the age of the Tukuringra complex in the Mongol-Okhotsk fold area
Biostratigraphic investigations in the western Amur-Okhotsk fold system resulted in new finds of microphytoliths in the metamorphic unit (Tukuringra complex), whose age has been conventionally specified in the range of Riphean-MiddlePaleozoic. The overlying Baldizhak unit, which in terms of material composition, metamorphic degree, and deformation differs substantially from the metamorphic unit, displayed Middle Paleozoic crinoids.
It is shown that in different parts of the Mongol-Okhotsk belt (Transbaikal region on the west to the left bank of the Zeya River on the east) the boundary of appearance of Devonian fauna is registered. Below this boundary occurs a Riphean-Middle Paleozoic volcanogenic siliceous terrigenous unit (up to 6 km thick.
I.V. Buchko, A.E. Izokh, M.Yu. Nosyrev
Sulfide mineralization of ultrabasite-basites of the Stanovoy megablock in the southern framing of the North Asian craton
This paper is an attempt to assess the prospects of a number of the Precambrian ultrabasite-basite intrusive complexes from the Stanovoy megablock in the southern framing of the North Asian craton with regard to copper-nickel mineralization basing on a comprehensive analysis of geological data and the results of investigations of mineralogical and chemical composition of sulfide minerals. At present the massifs of the Early Proterozoic (?) Ildeusskiy gabbro-verlite intrusive complex are the most promising for this type of mineral raw materials.
V.A. Stepanov, A.V. Melnikov, V.I. Palazhchenko, T.V. Makeyeva, V.I. Gvozdev
Original sources of platinum metal placer shows of the Dambuki cluster in the Upper Priamurye region
Discovered within the Dambuki ore-placer cluster, located in the southern margin of the Bryantinskiy protrusion of the Stanovoy fold-block area, sulphide massive platinum metal copper-nickel ores and their streaky-impregnated analogues are characteristic sources of removal of EPG minerals to placers. The carried out investigations of the revealed association of EPG minerals from the placer and minerals of sulphide copper-nickel ores allowed us to determine the connection between the original source and the association of EPG minerals from placers. The revealed original mineralization may be related to the Shanuchskiy type.
G.A.B.Osipenko, Ye.G.Sidorov, A.P.Kozlov, E.A.Landa, G.V.Ledneva, B.A.Markovskiy
Geochemistry of magmatic series from the Galmoenanskiy mafic-ultramafic massif, Koryakia
New data on the geochemistry of magmatic rocks from the Galmoenanskiy mafic-ultramafic massif, located in the Olyutorskaya tectonic zone, Koryakia, are presented with discussion of features of zoned (Alaskan-type) massif petrogenesis based on the obtained results interpretation. It is found that massifs of the studied type are characterized by stable and recurring petro- and geochemical parameters. The chemical composition of magmatic series determined in the structure of such massifs indicates a different source of melts for each of the series. The formation of the dominant dunite-wherlite-clinopyroxenite-gabbro rock sequence in the zoned-type massifs is related to fractionation of the initial magmatic melt, corresponding to primitive high-Mg basalts.
GV.O. Khudolozhkin, O.V. Avchenko
Investigation of the forms of existence of dissolved particles in the water-silica system in subcritical and supercritical conditions by the method of thermodynamic modeling
The solubility of quartz and polymorphs in water has been calculated on the basis of the new "Selector" (author Karpov I.K.) complex computer program at temperatures ranging to 740° C and at pressure ranging to 6 Kbar. The calculated solubility has been described along the three-phase boundary (quartz-water-fluid) and in the two-phase fields, quartz-water, and quartz-fluid. The calculated solubility of silica in water is in accordance with experimental results.
N.V. Boldovskiy
The structural and geological conditions of formation and distribution of underground waters in the East Asian volcanic belt
The principles of recognition of hydrogeological systems and hydrogeological stratification of the geological section of the East Asian marginal-continental volcanic belt have been worked out as the basis for defining the peculiarities of underground water formation and distribution. The recognition of hydrogeological systems is based on stratigraphic, petrographical, geostructural and hydrogeological regularities in the volcanic units of the belt. The worked-out hydrogeological stratification makes it possible to most optimally approach the problems of medium-scale hydrogeological mapping. The regularities of formation of underground water resources in the volcanogenic hydrogeological systems are considered.