Volume 20, 5, 2001
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Volume 20, 5, 2001 |
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Geophysics
V.V. Argentov, V.V. Zhigulyev, O.A. Melnikov, V.N. Patrikeyev. The experience in application of small-depth seismic investigations for revealing of structure of the Yuzhny-Sakhalin gas-water-mud volcano 3
V.I. Isaev, V.Yu. Kosygin, V.V. Sokolova. Prediction of oil-and- gas presence for the objects of exploration works in sedimentary basins of the Sakhalin Island from the results of geodensity and paleotemperature modeling 12
L. A. Maslov, V. E. Kuznetsov, O. S. Komova. Stress field due to crustal density inhomogeneities in the area of profile Obluchie - Datta Cape (Priamurye), relation to deep structure and geophysical fields 25
Sedimentology and Stratigraphy
F.P. Likht. Conditions for thin gold concentration in near-continental marine sedimentation (on sedimentation model for black shale-type deposits) 31
A.G. Klets, I.V. Budnikov, R.V, Kutygin, V.S. Grinenko. Middle Carbo-Early Permian event levels in Verkhoyaniye and regional stratigraphic scheme 45
I.D. Polyakova, L.A. Krol, G.N. Perozio, Ye.A. Predtechenskaya. Classification of sections and detailed mapping of domanikites 58
A.V. Kudymov. Early Cretaceous turbidites of the Northern Sikhote-Alin: structure, composition and sedimentation environments 72
P. Ya. Tishchenko, A.I. Svininnikov, G.Yu. Pavlova, T.I. Volkova, Ye.M. Il’ina. Dolomite formation in the Sea of Japan 84
Petrography and Geochemistry
A.A. Stepashko. Mantle lateral heterogeneity in South East Russia in the context of the Asian margin Mesozoic evolution 93
E.P. Lelikov, T.A. Emel’yanova, V.T. S’edin, M.M. Arakelyants, V.A. Lebedev. New radioisotopic dating for volcanites from the Sea of Japan and Sea of Okhotsk 118
L.F. Mishin, N.V. Berdnikov. Nature of high-alumina secondary quartzite by data of thermobarogeochemistry and isotopic analysis of oxygen and hydrogen 123
S.S. Zimin. Role of the boron compounds in the formation of tin deposits of a cassiterite-silicate formation (on the example of the Komsomolsk ore district) 140
Anniversaries
A.I.Khanchuk (to the 50-th birth anniversary) 151
V.I. Sukhov (to the 70-th birth anniversary) 153
V.V. Argentov, V.V. Zhigulyev, O.A. Melnikov, V.N. Patrikeyev
The experience in application of small-depth seismic investigations for revealing of structure of the Yuzhny-Sakhalin gas-water-mud volcano
The paper deals with the materials of small-depth seismic investigations of the central near-crater gryphon part of the Yuzhny-Sakhalin gas-mud volcano. Three layers were distinguished from P-wave velocities. The lower high-velocity layer corresponds to the volcano basement, the mid-velocity layer corresponds to the early diagenesed products of the volcanic activity, the low-velocity layer corresponds to the weakly diagenesed products of recent eruptions or saturated with water and gas clay mass filling the intermediate chamber and the incurrent canals in the volcano basement. The intermediate chamber, about 7 m thick, is located at the boundary between the basement and the cover overlapping it beneath the most active group of high ( about 0.5 m) gryphons. The confinement of maximum values of the products accumulated in the process of the volcano activity to the near-summit part of the hill with gryphons testifies to the steadily fixed position of the main volcano incurrent canal beginning from the moment of its relatively recent origination. The obtained data allow us to recommend small-depth seismic investigations to study other mud volcanoes of the Sakhalin Island.
V.I. Isaev, V.Yu. Kosygin, V.V. Sokolova
Prediction of oil-and- gas presence for the objects of exploration works in sedimentary basins of the Sakhalin Island from the results of geodensity and paleotemperature modeling
Methods, experimental data and results of geodensity, paleotectonic and paleotemperature modeling of the sedimentary deposits of the Nysh–Tym’ trough of the Sakhalin Island were considered. Direct sings of a degree of organic matter katagenesis and conditions for the formation of hyndrocarbon accumulations – vitrinite reflectance and the results of fluid tests from deep wells - were taken as reference data. Schematic maps of distribution of in-situ unconsolidations of the Okobykaisky deposits and distribution of maximum paleotemperatures, prediction of HC phase state in Okobykaiskiye, Daginskye and Uininsky deposits were compiled. Local objects in the Okobykaisky deposits are recommended for exploration works with an account of the lithological and paleotemperature factors.
The results of the test of automated technology of geodensity modeling and paleoprofiling developed in Dalinformgeocentre were summed up for the solution of problems of prediction in petroleum geology for four sedimentary basins of Sakhalin. An actual task was formulated for implementation of mathematical models on modern computer equipment and also technology of oil-and-gas presence, applying new numerical methods of modeling of non-stationary geophysical fields for solution prediction problems within 34 sedimentary basins of the Far East and Northeast of Russia.
L. A. Maslov, V. E. Kuznetsov, O. S. Komova
Stress field due to crustal density inhomogeneities in the area of profile Obluchie - Datta Cape (Priamurye), relation to deep structure and geophysical fields
A deep structure model of the Bureya Massif and Sikhote-Alin fold system juncture area is constructed on the basis of seismological and geoelectrical crust and upper mantle sections and materials of geological and geophysical studies. The recent stress field is calculated from distribution of the revealed anomalous densities using the method of analytical solution of the problem of mechanics. The stress pattern obtained is interpreted as an indication of the new destructive crust and upper mantle processes in the Northern Sikhote-Alin: subsurface areas of the increased tangential stresses control shallow seismicity; an increased deformation of rocks in areas of the maximum stresses stipulates an upwarping of the asthenosphere top; localizations of the weakened zones cause the formation and evolution of magma chambers.
Conditions for thin gold concentration in near-continental marine sedimentation (on sedimentation model for black shale-type deposits)
The review of materials on metallogeny for the so-called «thin- or invisible gold» (TG) has enabled us to make the origin of the Nevadian-or Carlin-type deposits (CTD) clear in the black shale formations (BSF). The resemblance of the above-mentioned deposits with sediments from near-continental marine basins provides a way for determination of the specific conditions for sedimentation and the mechanisms for TG supply, migration and sedimentation favored for TG concentration in the deposits related to the black shale formations. TG concentration in CTD appears to be primary and sedimentogenic. The superposition of succeeding metamorphic processes leads to redistribution of the primary con?entrations and the initiation of transformed ore and mineral associations giving an impression of the genetic separation of the sedimentation and ore formation. The possibility of the primary gold concentration is based on the mechanisms and volumes of gold supply from the land along with the terrigenous material and TG accumulation in sediments under the influence of the organic material, including microorganisms. It is noted that cold water and gas hydrocarbon sources on the sea bottom (similar to the recent seep-venting systems) are an important factor in the formation of the organic carbon potential in BSF. The latter are characterized by specific carbonate rocks, which might be formed and primary thin gold might be concentrated. They are similar to those formed by the above-mentioned sources and reef communities. Some bottom regions within the recent basins have been chosen as actualistic sedimentation models for the CTD, where the formation of homologues for BSF is possible and primary TG concentration, respectively.
A.G. Klets, I.V. Budnikov, R.V, Kutygin, V.S. Grinenko
Middle Carbo-Early Permian event levels in Verkhoyaniye and regional stratigraphic scheme
A regional stratigraphic scheme for Verchoyaniye is offered on the basis of study of the geological sections of Western Verchoyaniye and data on other regions. Middle Carbo-Lower Permian stratohorizones have been re-distinguished, restored or substantiated in addition. They are Imtandjinian, Solonchanian, Barainian, Setlandinian, Khorokitian, Echiian and Tumarinian. To distinguish regional horizons sedimentational transgressive-regressive cycles and associated stages of faunal evolution have been taken as a basis. The sequence of complex biostratigraphic zones has been established, namely: Balakhonia insinuata-Verkhotomia tukulaensis, Verkhotomia tukulaensis-Verchojania cheraskovi-Jakutoceras aldanicum, Settedabania stepanovi-Christioceras domochotovi for the Middle Carboniferous; Settedabania stepanovi-Eoshumardites artigensis, Jakutoproductus tatjanae-Muirwoodia mammata-Eoshumardites lenensis, Jakutoproductus tatjanae-Plicatiferina neoplicatilis-Plicatospiriferella costata for the Upper Carboniferous; Jakutoproductus protoverchoyanicus, Jakutoproductus verchoyanicus and Jakutoproductus rugosus for the Lower Permian. Out of them, seven biotic event levels with maximum correlative potential were recognized. They coincide in time with high sea levels of the World Ocean.
I.D. Polyakova, L.A. Krol, G.N. Perozio, Ye.A. Predtechenskaya
Classification of sections and detailed mapping of domanikites
The Bazhen suite is considered as an object for studying Domanikitian deposits. Lithologo-geochemical indentification of data on standard logging has been worked out, based on which classification of sections is offered and mapping, at a scale of 1:500 000, has been conducted in the southeast and central part of the West Siberian plate. It has been established that the most gamma-active parts of the section are composed of clayey-cherty-sapropelic rocks. They are characterized by increased and maximum concentrations of organic matter, mostly by colloalginite. Types of the sections were distinguished by the ratio and classes - by the distribution of rock groups reflected on the figure by the curve of the apparent resistance through the entire suite thickness. The peculiarities of the section composition and structure depend upon the bottom relief and the depth of the marine basin which transgressed into the southern part of the west Siberian plate at the initial and particularly middle evolution stages. Section types and classes prospective for oil search have been revealed.
Early Cretaceous turbidites of the Northern Sikhote-Alin: structure, composition and sedimentation environments
Turbidities from the northern part of the East Sikhote-Alin trough have been investigated. They are composed of thick sand, sandy-argillaceous flyshoid rocks with gradational bedding. Based on the clastics composition, oblique lamination and flysh rhythmicy, reconstruction of theEearly Cretaceous flows and paleoslopes have been made. It appeared that turbidites have originated from mud flows directed from the southeast to the northwest; the feeding province of the turbidites was located to the southeast from the sedimentation area.
P. Ya. Tishchenko, A.I. Svininnikov, G.Yu. Pavlova, T.I. Volkova, Ye.M. Il’ina
Dolomite formation in the Sea of Japan
Evidences for low temperature formations of dolomite in the Sea of Japan are presented in this paper. Equation of dolomite solubility as function temperature, salinity and pressure have been obtained for application to seawater. Thermodynamic calculations of saturation degrees of aragonite, calcite and dolomite were carried out. From thermodynamic calculations and hydrochemical observations of sea and pore water, a hypothesis of low temperature dolomite formation is suggested. According to this hypothesis, different mineralogical and textural forms of calcium carbonate are dolomitized in the sediments under high concentrations of carbon dioxide resulted from the degradation of organic matter in the sediments.
Mantle lateral heterogeneity in South East Russia in the context of the Asian margin Mesozoic evolution
A new method for studying the upper mantle lateral heterogeneity has been suggested based on deciphering intraplate basalt regional compositional variations. Three mantle blocks have been identified the Cenozoic alkali basalt of each of which is characterized by its own variational structure reflecting the composition of deep melt generation domain. Mantle structure is concordant with the main peculiarities of regional tectonics. It allows considering mantle blocks as the plates the Mesozoic interaction of which formed structure of lithosphere in South East Russia. A geodynamic model has been proposed which takes into account the structure of the region both at the crustal and mantle levels. At the first (T-J) stage of evolution at the Mongol-Okhotsk Ocean closure, blocks of lithosphere were extruded along the faults in the north-eastern direction. Early Cretaceous reorganization of the strain field caused general compression (second stage) as a result of which the block occupying the central position was curved and bent in the north-western direction. A big bay formed in its back part, and the Khabarovsk complex turbidite formed within it.
E.P. Lelikov, T.A. Emel’yanova, V.T. S’edin, M.M. Arakelyants, V.A. Lebedev
New radioisotopic dating for volcanites from the Sea of Japan and Sea of Okhotsk
New radioisotopic datings (K-Ar method) of Meso-Cenozoic volcanites from the Sea of Japan and the Sea of Okhotsk are obtained. They have enabled us to reason the age of the distinguished volcanic complexes. Basalts from the volcanic edifices of the Japan Sea Basin were determined the Middle Miocene – Pliocene (13.1–4.5 Ma) in age, which is well correlated with the geological evolution of the Sea of Japan. New datings for the basalts from the continental slope of Southern Primorye (11.1Ma) confirm their age being similar to the volcanites of the Neogene basalt plateaus of Southern Primorye, to which they are very similar in mineral and chemical composition. The obtained datings for the rocks from andesite series of the Northern Yamato (24.7, 21.5 Ma) show that they are concordant with the age of the volcanites of trachyandesite complex, that allows combining them into one Oligocene-Early Miocene complex. In the Sea of Okhotsk we obtained datings by the volcanite samples of three complexes: Cretaceous, Paleogene, and Pliocene-Pleistocene. Cretaceous magmatic rocks make part of the basement of large rises in the Sea of Okhotsk, and Paleogene and Pliocene - Pleistocene complexes illustrate the stages of the Cenozoic tectono-magmatic activation of the region.
Nature of high-alumina secondary quartzite by data of thermobarogeochemistry and isotopic analysis of oxygen and hydrogen
Fluid inclusions and isotopy of oxygen and hydrogen were studied in secondary quartzite from Krasivy, Belaya Gora, Gryada Kamenistaya, Shelekhovskoye, Mago and Brinnerovskoye deposits. It was shown that high-alumina secondary quartzite, a genetically single group of metasomatic rocks, form at the temperature ranging from 190 to 470°C under near-surface conditions (P<100 bar) when acidic rocks undergo the influence of heterogenic fluid with mainly meteoric isotopic composition. For their origin the acidic leaching environment is needed which is created in the process of boiling and disproportioning of hydrothermal fluid due to evolution of chlorine and sulfur compounds. During this hydrothermal system experiences acidic-alkali layering: above the fluid boiling zone there is acidic layer (subscreen horizons, area of secondary quartzite formation), below - alkali layer (area of mineralization).
The model suggested for secondary quartzite formation agrees with geological data on the form and position of their bodies in host rocks. A previous conclusion that secondary quartzite accompanies the underlying mineralization being (together with ores) an integral part of a completely manifested hydrothermal system of chalcophile profile.
Role of the boron compounds in the formation of tin deposits of a cassiterite-silicate formation (on the example of the Komsomolsk ore district)
The first part of the paper considers the role of borohydrides in geological processes. These compounds came from the deep-seated zones of the mantle and penetrated into the centers of granitoid magma in the earth’s crust through the weakened zones. At high (1200 K) temperature, interacting with melt water, borohydrides decompose into H2 and B2O3. Hydrogen creates the reduction regime in the center, and above it its reaction with oxygen results in the formation of diatremes. B2O3 remains in the melt and under the action of hydrogen and carbon of black shales favors the formation of borides, preceeding oxides and tourmaline.
In the second part of the paper, the main features of geology, metallogeny, and geochemistry of the Jurassic-Cretaceous magmatic rock communities of the Komsomolsk ore district are discussed. Among the four magmatic complexes (Purilsky, and others), the stable positive correlation of boron with such elements as Zn. Ni, Cu, Pb, and Sn is observed only in the rocks of the Silinsky granitoid complex. The points of intermediate rocks (on boron and metal) in the Silinsky ore-bearing granitoids are arranged on the trends of known in the literature or expected borides.
Borides were formed under the reduction regime and prior to cassiterite crystallization. The latter is suggested to be formed after and due to tin boride oxidation and subsequent metamorphism during new magmatism bursts.