Volume 21, 1, 2002
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Volume 21, 1, 2002 |
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The 20-th anniversary of the journal "Tikhookeanskaya Geologiya" 3
M. D. Gerasimenko, Minoru Kasahara. Tectonic plate motion and deformation by space geodesy measurements (on the question of fixing kinematics reference frame). 5
A.V. Parfeevets, V.A. San'kov, A.I. Miroshnichenko, and A.V. Lukhnev.Evolution of the Earth's crust stress, the Mongol-Baikal mobile belt 14
I.A. Tararin, V.M. Chubarov, and T.M. Filosofova. Basification of plagiogneisses at the contact with gabbroids of the Yurchiksky massif from the Ganalsky Ridge of Kamchatka 29
V.N. Voevodin. Prototectonic elements of intrusive granitoids as an indicator of mechanism of their formation and ore-generating possibilities 48
A.I. Malinovsky, A.N. Filippov, V.V. Golozoubov, V.P. Simanenko, and V.S. Markevich. Lower Cretaceous deposits of the Kema river area (Eastern Sikhote-Alin): sedimentary filling of a back-ark basin 52
B.I.Pavlyutkin, and T.I.Petrenko. Stratigraphy of Cenozoic deposits of the Ivanovsky Basin, South Primorye 67
T.N. Palechek. Campanian-Maastrichtian Radiolarians of the Koryak-Kamchatka region 76
A.I.Khanchuk, B.L.Zalishchak, V.A. Pakhomova, E.G. Odarichenko, and V.I.Sapin. Genesis and gemology of sapphires from the Nezametny deposit (Primorye) 89
L.B. Hershberg, E.V. Mikhailik, O.V. Chudaev, V.A. Polinovskiy, M.M. Yurinets, and V.P. Utkin. Geological peculiarities and ore deposits of the Roskomnedra Guyot, the Magellan Seamounts (Pacific Ocean) 96
V.I. Isaev, A.A. Yurchuk, N.V. Shpakova, S.I. Voikova, O.S. Isaeva, and V.V. Sokolova. The State Far Eastern Regional Geological and Geophysical Database on Oil and Gas (a model of realization) 111
Anniversaries
Yuriy Mikhailovich Pushcharovskiy (to the 85-th anniversary) 127
Alexandr Ivanovich Jamoida (to the 80-th anniversary) 129
Necrologies
Shuldiner Victor Izrailevich (1931-2001) 131
Notes for Contributors
M. D. Gerasimenko, and Minoru Kasahara
Tectonic plate motion and deformation by space geodesy measurements (on the question of fixing kinematics reference frame)
The purpose of this research is investigation of a new algorithm for fixing the three-dimensional kinematics reference frame of space geodetic stations in which only vertical components of quasi-stable site velocities for every X, Y, Z direction are used. This kinematic reference frame does not depend upon any geological plate model and thus is free from the errors coming from the uncertainties of such a model. On the contrary, it is possible to verify such plate model as NNR NUVEL-1A using only geodetic information itself. The algorithm has been applied to the VLBI data (NASA GSFC VLBI terrestrial reference frame solution number 1122, June, 1999). We have used for the analysis the estimated rate of change of 400 baseline vectors between 59 VLBI sites. We have found fairly close agreement between our solution and international terrestrial reference frame solution ITRF97. That is the KRF can be fixed exclusively using space based measurement itself. Our solution almost does not yield ITRF97 solution in respect of NNR NUVEL-1A plate model. It is despite of the fact that ITRF97 network coverage the largest set of globally distributed VLBI, SLR, DORIS and GPS terrestrial space geodesy stations. In addition, we have found that the most likely change of the Earth's radius is near -0,3 mm/yr with estimated error 0,1 mm/yr that is in good agreement with reliably established determinations of this value.
A.V. Parfeevets, V.A. San'kov, A.I. Miroshnichenko, and A.V. Lukhnev
Evolution of the Earth's crust stress, the Mongol-Baikal mobile belt
The evolution of the state of stress of the Mongol-Baikal mobile belt, which is part of boundary forming between the Eurasian plate and Amur microplates, is investigated on the basis of tectonophysical analysis of tectonic fracturing. The paleostress fields are ranged with the use of spatial characteristics of a three-component tensor and stress-ratio R = (s2 - s3)/(s1 - s3), which determines the form of stress ellipsoid. It is shown that the structures of the central part of the Baikal rift system and its northeastern flank developed in terms of strike-slip regime of the deformation at the initial stage of rifting, and in those of extension and transtension regimes at the late stage of it. The stress field of the southwestern flank of the rift system evolved from the regime of transtension and strike-slip to that of transpression. A relatively short-term episode of the northwestward compression (late Late Miocene-early Pliocene), preceeding to that of fast rifting, is revealed. Neotectonic structures of North Mongolia and Tuva developed under conditions of compression and transtension, tending to increase of a strike-slip component of displacements along the major faults at the north-north-eastward compression.
I.A. Tararin, V.M. Chubarov, and T.M. Filosofova
Basification of plagiogneisses at the contact with gabbroids of the Yurchiksky massif from the Ganalsky Ridge of Kamchatka
On the contact of amphibole gabbro of the Yurchiksky massif with plagiogneisses of the ganalsky series, a distinct column of replacement is obvious. It includes zones of hornfels formation and metasomatic alteration of the initial substrate, which is replaced in part by melting with the formation of mixed rocks. Dissolution and melting of the initial substrate in the intruding melt are responsible for selective assimilation of the replaced rock components by newly-formed melt and evacuation of the components that are in excess relative to the gabbroid eutectics. This results in displacement of the eutectic and cotectic compositions of the originating melts towards the andesite temperature minimum.
Comparison of the rock compositions from the metasomatic zones shows that in the direction from the rear zone outward a considerable amount of SiO2 is evacuated and FeO, MgO, and CaO are supplied. This makes the initial plagiogneisses substrate more basic and its composition approximate to that of the intruding mafic melt in the replacement area.
V.N. Voevodin
Prototectonic elements of intrusive granitoids as an indicator of mechanism of their formation and ore-generating possibilities
Prototectonic analysis has been traditionally used to determine the interior composition and general structure of granitoid plutons. However, the possibilities of such an analysis might be widened because heterogenous originally structural elements of the granitoid massives fixed in the rock texture and structure bear different geological information indicating conditions and mechanism of massif formation, and thus can be used to detect their ore-generating possibilities. The method for solving the problems of formation mechanism and ore-generating possibilities of granitoids from prototectonic elements is also discussed. Examples are provided by two sharply contrast raws of granitoid massives of mesozoids of East Russia: folded batholitoid massives and older discordant orogenic massives which differ in structure and ore content.
A.I. Malinovsky, A.N. Filippov, V.V. Golozoubov, V.P. Simanenko, and V.S. Markevich
Lower Cretaceous deposits of the Kema river area (Eastern Sikhote-Alin): sedimentary filling of a back-ark basin
Structure and composition of the Lower Cretaceous volcano-sedimentary deposits of the Kema river basin, belonging to the Kema terrane (Eastern Sikhote-Alin), have been more exactly defined by lithologic and stratigraphic investigations. Stratigraphic sequence of these deposits is as follows: Meandrovsky suite ( Barremian (?) - Early Aptian); Kemsky suite (Early Aptian - Late Albian), which is divided into three subdivisions, and Luzhkinsky suite (Middle toLate Albian). Among these deposits different gravitation sediments are widespread: from immature turbidites up to submarine landslides, associating with the products of submarine volcanism. The Kema terrane is part of the lateral row of adjacent and synchronously developing tectonic elements of a single Moneron-Samarginsky island-arc system. The location of the terrane, its genetic composition, thicknesses of the deposits, and nature of its filling and relations with the adjacent lateral elements indicate that the deposits had been formed in the near slope environments, and the terrane fits best the concept of a back-arc basin.
B.I. Pavlyutkin, and T.I.Petrenko
Stratigraphy of Cenozoic deposits of the Ivanovsky Basin, South Primorye
On the basis of new data, a scheme of division of Paleogene-Neogene volcanogenic-sedimentary deposits has been first suggested for the Ivanovsky basin, a Cenozoic tectonic structure, which is located in the southern margin of the Khanka massif. The distinguished stratigraphic units are described in terms of their lithological and paleobotanic composition and correlated with adjacent Cenozoic basins. The basin under consideration is placed in earlier adopted scheme of structural and formational zonation of South Primorye for the Paleogene-Neogene.
T.N. Palechek
Campanian-Maastrichtian Radiolarians of the Koryak-Kamchatka region
Campanian-Maastrichtian Radiolarian assemblages of the Russian Far East including Koryak Upland, Olyutorsky Peninsula, Kamchatka Isthmus, Western and Eastern Kamchatka are compared. Taxonomic composition, morphology of the Radiolarian shells, diversity and abundance of orictozenoses are discussed. The studied Radiolarian complexes are correlated with the stratigraphic scheme for Cretaceous volcanic-siliceous sediments of the Bering Sea region and zonal scales of the adjacent territories. Based on these data, conditions for deposition of Late Cretaceous sedimentary-volcanogenic complexes of the Russian Far East were reconstructed.
A.I. Khanchuk, B.L.Zalishchak, V.A. Pakhomova, E.G. Odarichenko, and V.I.Sapin
Genesis and gemology of sapphires from the Nezametny deposit (Primorye)
The paper presents original materials on the research of inclusions in sapphires from the Nezametny placer deposit, and also minerals of a granite - porphyry heavy fraction of a gold-ore native stock from the Nezametny deposit, where loose sapphires, hyacinths, and shpinels occur. Chemical analyses of corundum and mineral inclusions are made. Based on the established association of mineral inclusion phases - columbite, albite, zircon, zinc-bearing hercynite, rutile, glass composition, and presence of accessory corundum in granite-porphyries and granosyenite- porphyries, it was concluded that rare-metal pegmatites, greisens, and metasomatites associated with Mesozoic granitoid bodies being widespread in the area, are the source of the corundums studied.
L.B. Hershberg, E.V. Mikhailik, O.V. Chudaev, V.A. Polinovskiy, M.M. Yurinets, and V.P. Utkin
Geological peculiarities and ore deposits of the Roskomnedra Guyot, the Magellan Seamounts (Pacific Ocean)
The paper first presents the results of the geological and geophysical study and considers the peculiarities of geological structure and ore content in the Roskomnedra (MG-36) Guyot, which is part of the southeastern termination of the Magellan Seamounts. The guyot consists of basalts (95%) and breccias (5%) which are covered by cobalt-rich manganese crusts (CMC). Resources of dry crust ores in the bathymetric interval of 1300-1600 m are 12,5 million tons. These resources can provide the mining exploitation during 20 years due to uniformity of geological structure of the ore beds and high ore-bearing coefficient (0,86); ore bed inclinations on the guyot are less than 7°, high parameters of economic value (Co-0,595%, Coapprox. - 1,73%, CMC productivity by Coapprox. - 1,65 kg/m2, and coefficient of ore content - 0,86 ), as compared with the Dalmorgeo and IOAN guyots, and the lowest content of deleterous admixtures and slag-forming components.
V.I. Isaev, A.A. Yurchuk, N.V. Shpakova, S.I. Voikova, O.S. Isaeva, and V.V. Sokolova
The State Far Eastern Regional Geological and Geophysical Database on Oil and Gas (a model of realization)
A conceptual model of the State database of geological and geophysical data of the Far Eastern oil-and gas region is being developed in the state concern (SC) "Dalinformgeocentre". The distinctive features of realization of the informational and logical structure consist in integration of concepts of various categories of users of petroleum geology, application of standards of State Bank of Numerical Geological Information, and industrial relation systems of database control and GIS- systems, invoking a specialized Norwegian system of Petrobank for loading-unloading of primary geophysical data of Sakhalin shelf projects, in stage-by-stage preparation of the database for operation. Unstable and extremely low level of financing of works is a general regulator of projecting.
The integrated numerical packages are prepared for operation on individual sedimentary basins in the form of an non- network graphic user interface with application of available program and technical means. The nearest perspectives of the development of a database are to create the customer - server technology in a mode of deleted access of an external customer.