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Vol. 1 (1998 year), No. 3
Vetrin V.P., Ovchinnikova G.V., Neimark L.A., Gorokhovsky B.M., Smirnov Yu.P.
Muscovite-Microcline Metasomatites in Rocks of the Archaean Complex of the Kola Superdeep Borehole: Stages of Formation and Sources of Substance
Muscovite-microcline metasomatites on gneisses of the Archaean complex of the Kola superdeep borehole are found out in the bottom part of the section on the depth 12172-12235 m and by the geological position, structure and age are correlated with garnet-like rocks of the metasomatite formation occupying the area not less than 300 km2 in the Archaean rocks of the Pechenga riftogenic structure's northern frame. The metasomatite formation occured in conditions of increased potential of CO2, P, F, B and was accompanied by increase in gneisses of the content substratum as elements of siderophile (Fe, Ti, Cu, Ni, Co, Cr, V), and litophile (K, Rb, Ba, Nb, Zr, Y, TR, Pb, Th) group as well. These features of the structure are peculiar for subalkaline rocks of the early-orogenic trachybasaltic formation, which rocks have mantle origin and, as it is supposed, were a source of fluids rich of carbonic acid. On the Pb-isotope data, lead in the metasomatites was formed by mixing of mantle lead introduced by fluids with lead from gneiss substratum with age 2.8 Ga. The more radiogenic isotope structure of Pb of some plagioclases adequate to lead of upper crust formations, does not contradict the assumption of reworking of Pb-Pb systems of feldspars from muscovite-microcline metasomatites during intrusion of anatectic bodies of the Svecofennian granites.
(in Russian, стр.8, fig. 4, tables. 2, ref 13, MS Word 95, MS Word 95 204 Kb)
Vol. 5 (2002 year), No. 1
Kozlov N.Ye., Martynov Ye.V., Kozlova N.Ye., Ivanov A.A., Smirnov Yu.P. and Kolodkina A.V.
Geologic-petrogeochemical features and metamorphism of Archaen rocks of the North-Eastern Pechenga as a criteria of their choice as deep homologues of the Kola Superdeep Borehole
The paper has been based on materials and data of the Geologic institute of KSC RAS and Scientific Centre "Kola Superdeep" and also original methods of information processing. The work has proved that the formations of the northern and north-eastern frame of the Pechenga structure can be considered as homologues of the Archaean superdeep borehole metamorphites most suitable for comparison at a mineral level.
(in Russian, стр.10, fig. 6, tables. 1, ref 24, MS Word 95, MS Word 95 1110 Kb)
Vol. 10 (2007 year), No. 1
Kozlova N.Ye., Sherendo T.A., Kozlov N.Ye., Garaeva A.A., Smirnov Yu.P.
Comparison of ore mineralization of iron-siliceous rocks in Archaean unit IX of the Kola Superdeep Borehole and its geospace
The paper considers the reasons of occurrence of biocorrosion, its influence on technical characteristics of the hull and seaworthy qualities of a ship.
(in Russian, стр.9, fig. 3, tables. 3, ref 13, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 1
Skufin P.K., Lyutoev V.P., Yakovlev Yu.N., Smirnov Yu.P., Glukhov Yu.V., Kotova E.N.
Properties and structural peculiarities of rock forming minerals and Early Proterozoic sedimentary rocks in the SG-3 section and their homologues at the surface
Actinolites and hornblendes from the SG-3 Archaean rocks and from the surface Archaean complex (Allarechka block) have been studied. The Allarechka block used to be considered a surface analogue of the SG-3 Archaean complex. The mineral structure, the nature and degree of structural defects have been investigated by X-ray powder diffractometry, infrared and Mossbauer spectroscopy. The chemical composition was determined by the wet chemistry and microprobe methods. The comprehensive investigations resulted in establishing composition stoichiometry of deep and surface amphiboles. Vacancies are present only in rare samples and in minor amounts. The majority of the studied amphiboles had a high degree of the unit cell deformation and its elongation along the c axis. A high and about the same degree of Fe2+ and other cations was observed in both groups of specimens. At the same time the patterns of the site occupation by Fe2+ are slightly different: Fe(M3)>Fe(M2)?Fe(M1) – for deep samples and Fe(M3)>Fe(M1)>Fe(M2) – for surface ones. The degree of iron oxidation is established to be similar (from 5 to for 20 %) for both surface and deep samples. Actinolite and low-alumina hornblende have no marked difference in their structural state at a depth of 7900-11350 m and at the surface. The data on the crystalline substance state at the crust deep zones may be useful for reliable interpretation of geophysical measurements, development of correct models of the crust structure and for choosing the proper sites for disposal of radioactive wastes. The structural state of amphibole (actinolite, low-alumina hornblende) from amphibolite and crystalline schist of the SG-3 Archaean complex and their surface homologues has been studied. The aim was to elucidate whether the structural state of those amphiboles differs and whether the amphiboles from the SG-3 Archaean rocks preserve any information about the physical state of the crystalline substance at great depths during their extraction to the surface. We have studied the composition, degree of iron oxidation, nature and degree of structural defects and the availability of various forms of water in the structure of amphiboles from the SG-3 Archaean rocks (7930-11330 m) and their surface homologues from the Allarechka block (southern framing of the Pechenga structure). According to the modern nomenclature (Leake, 1997), the actinolite and hornblende pertain to the calcic amphibole group.
(in Russian, стр.19, fig. 11, tables. 8, ref 25, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 1
Gordienko V.V., Gordienko Vl.Vl., Kalinicheva G.I., Olkhovaya E.A., Rumayntseva E.V., Timokhina L.A., Guberman D.M., Smirnov Yu.P., Yakovleva A.K., Yakovlev Yu.N.
Granitic pegmatite of the Kola Superdeep Borehole (vertical mineral-geochemical zoning and genesis problems)
The basement of the Early Proterozoic Pechenga palaeorift was penetrated by the Kola Superdeep Borehole (SG-3) at a depth of 6842-12262 m. In contrast to similar rocks framing the Pechenga palaeorift, Archaean rocks of SG-3 were affected by Proterozoic magmatism and metasomatism related to the rift development. The most intense Proterozoic processes were an intrusion of numerous mafic-ultramafic bodies, retrograde metamorphism and synmetamorphic migmatization, and emplacement of postkinematic granites. Most Proterozoic processes were determined to have been related to mantle sources. The overall amounts of Proterozoic material introduced into the Archaean rocks penetrated by the lowermost part of SG-3 coupled with the remobilized material of the Archaean crust is estimated at ?30 % (?12-15 % amphibolites, ~3 % granite veins, ~15 % migmatized rocks). Thus, searching for homologues to the SG-3 Archaean rocks does not lie only in a quest of analogous rocks in the frame of the Pechenga structure, but in the interpretation of the Proterozoic processes that have changed quantitative ratios and composition of the palaeorift basement rocks.
(in Russian, стр.14, fig. 3, tables. 7, ref 11, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 1
Kozlov N.Ye., Martynov Ye.V., Kozlova N.Ye., Kirillova L.D., Smirnov Yu.P.,
On petrochemical classification of amphibolite from the Archaean section of the Kola Superdeep Borehole
The data on the structure of the Kola Superdeep Borehole geospace at a depth and on the surfaces based on especially detailed study and mapping of structural-material inhomogeneities of various nature, ages and scales have been presented. Heterogeneity of thermo-metamorphic events in the complexes of the Archaean base and Palaeoproterozoic cover has been analyzed. On this basis a new geodynamic model of the geospace structure and evolution has been created.
(in Russian, стр.7, fig. 3, tables. 2, ref 16, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 2
Spisiak J., Dostal J., Hovorka D., Meres S., Smirnov Yu.P.
Geochemical and mineralogical patterns of Proterozoic metapicrites from the Kola Superdeep Borehole (SG-3)
Palaeo-volcanological analysis of volcanites from the Majarvi, Pirttijarvi and Orshoaivi Fms in the SG-3 section and near-surface zone (structural boreholes IX and X) showed a considerable structural similarity of these formations. The volcanites of the formations under consideration can be considered to be homologous rocks taking into account the lateral changes in volcanite composition and in the conditions of metamorphism with depth. Petrogeochemical analysis shows that the Majarvi, Pirttijarvi and Orshoaivi volcanic Fms have different composition, volume and facial peculiarities in different tectonic blocks. The volcanites from the Majarvi Fm are similar to the surface and near-surface homologues in their chemical composition which is indicative of the isochemical nature of metamorphic processes from prehnite-pumpellyite to amphibolite facies. Abyssal samples are just slightly depleted in ferric iron. At the same time the study of Lower Jatulian volcanites from the Pirttijarvi and Orshoaivi Fms points to a great difference in composition of the abyssal rocks and their surface homologues. As compared with the surface rocks, the abyssal rocks are subject to averaging and homogenization of the composition. Volcanites from the Pirttijarvi Fm are rich in Al2O3, partly in alkali, but depleted in ferric iron and silicic acid. The volcanites from the Orshoaivi Fm show a rapid growth in subalkaline rocks (from 20 to 70 %), mainly alkaline basalts, at the cost of a great enrichment in alkalies of initial ferrobasalts which account for more than 50 % in the surface volcanites. A number of factors point to the relation between the dislocation metamorphism of volcanites from the SG-3 section and the influence zone of the deep Luchlompolo fault. Sulphide specialization of the Majarvi Fm volcanites with minor oxide content has been established and oxide specialization of volcanites from the Pirttijarvi and Orshoaivi Fms has been confirmed. Formational analysis of volcanites from the Pechenga structure and the whole Polmak-Pechenga-Varzuga greenstone belt (PVB) allowed establishing a cyclic change in rift and orogenic tectonic regimes in the course of its formation. This cyclicity contradicts the generally accepted model of its formation as a rift structure. Two full endogenic cycles about 400 Ma each have been established for the PVB: Sumian-Sariola-Jatulian (2550-2115 Ma) and Ludia-Kalevian-Vepsian (2115-1700 Ma). Divergent basic-ultrabasic volcanites of the Sumian-Sariola-Jatulian cycle are confined only to the foot section of the Majarvi Fm. As a whole, the volcanite section of this cycle is represented by convergent products of magma differentiation of the orogenic tectonic regime – medium-acid rocks from the Majarvi, Pirttijarvi and Orshoaivi Fms. By its geodynamic nature, the PVB resembles polycyclic greenstone belt within which individual structures with rather autonomous development history – those of Pechenga, Imandra, Varzuga etc. have localized.
(in Russian, стр.13, fig. 7, tables. 4, ref 42, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 2
Kern H., Popp T., Gorbatsevich F.F., Zharikov A.V., Lobanov K.V., Smirnov Yu.P.
Seismic properties of rocks from the Kola Superdeep Borehole and their surface analogues: A comparative study simulating conditions at depth
The results of experimentally determined physical and mechanical properties of rock samples representing two various units of the Kola Superdeep Borehole (SG-3), Proterozoic and Archaean, and their surface analogues have been presented. The bulk and matrix density, porosity, strength and deformational characteristics for all rock samples have been found and mutual comparison of the results has been carried out.
(in Russian, стр.4, fig. 0, tables. 0, ref 14, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 2
Smirnov Yu.P., Gorbatsevich F.F., Nikitin A.N., Tyuremnov V.A.
Description of structure, texture and anisotropy of rocks from the Kola Superdeep Borehole section.
The stress state of rocks in the area of the German continental deep hole drilling (Kontinentales Teifbohrprogramm der Bundesrepublik Deutscland – KTB) has been studied by the boundary elements method. A comparative analysis of the stress-strain state of rocks of the Kola Superdeep Borehole (SG-3) and German Continental Deep Hole (KTB) has been carried out.
(in Russian, стр.11, fig. 4, tables. 0, ref 28, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 2
Schulze K.C., Kuempel H.-J., Guberman D.M., Morgachev V.I., Pevzner S.L., Pisarnitsky A.D., Simonova L.A., Smirnov Yu.P., Khmelinsky V.I., Yudin E.I., Yakovlev Yu.N.
Signatures of fluid level variations in the Kola Superdeep and two surrounding boreholes
Modern concepts of the deep structure of the earth crust based on the analysis and generalization of seismic data collected in the past 40 years and the Kola Superdeep Borehole record have been presented. The tomographic model of the Pechenga district has been characterized. Our knowledge of the layered pattern of the earth crust stratification has been updated, the geometry of seismic boundaries has been described more accurately and the crust-mantle boundary under the Pechenga structure has been found to be uplifted.
(in Russian, стр.8, fig. 6, tables. 0, ref 11, Adobe PDF, Adobe PDF 0 Kb)