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Vol. 10 (2007 year), No. 1
Bayanova T.B., Yakovlev Yu.N., Guberman D.M., Yakovleva A.K., Skufin P.K.
Isotopic investigations of age of the Archaean rocks from the Kola Superdeep Borehole section, Proterozoic Pechenga structure and its framing.
The results of the study of ore mineralization in the rocks from the three lower volcanic formations in the SG-3 Proterozoic complex and in their near-surface homologues cut by the structural boreholes IX and X have been presented. Sulfide specialization of volcanites from the Majarvi Fm has been found. Oxide specialization of rocks from the Pirttijarvi and Orshoaivi Fms has been confirmed. The distribution, evolution conditions and chemical composition of sulfides and oxides from volcanites have been studied. The main features of development, composition and late alterations of ore minerals could be related to two factors. The composition of sulfide from the Majarvi Fm vulcanite and oxide from the Pirttijarvi and Orshoaivi Fms in the SG-3 section is determined by a "depth factor" that caused a widespread occurrence of mineral solid solutions. Intense development of hematite and transformation of magnetite and ilmenite in volcanites of the Pirttijarvi and Orshoaivi Fms in the SG-3 section are explained by the influence of the regional Luchlompolo fault. High contents of isomorphous admixtures – PGE, Se and Co in sulfides, V, Ti and Mn in oxides that were not observed earlier in the SG-3 section and geoblock as a whole have been established in all major minerals from the formations deep levels.
(in Russian, стр.12, fig. 9, tables. 3, ref 29, 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
Guberman D.M., Larikova T.L., Morozov Yu.A., Smulskaya A.I., Sholpo V.N., Yakovlev Yu.N.
Structure and evolution of the Kola Superdeep Borehole geo-space based on results of the study of structural-material heterogeneities
Some aspects have been shown in the paper: a general characteristic of granite pegmatites cut by SG-3 and data on structural variations of their "end-to-end" pegmatite-forming minerals – feldspar, garnet and mica – depending on the depth of pegmatite occurrence. The existence of vertical geochemical zonality (VGZ) of pegmatite vein system (PVS) of KSDB is proved statistically (more than 300 monomineral samples). VGZ, which has complicated polystage reciprocal character, is caused by contrast migration of chemical elements – indicators (CEI) at free moving of pegmatite-forming environment within the geochemical stages of the system. The range of such migration for PVS from SG-3 achieves more than 3 km along the vertical, which has denied the existing idea about formation of similar PVS "in situ". VGZ is controlled by a pressure drop and temperature gradient. The latter is estimated by two-feldspathic equilibrium at 25?5°C/km. This feature characterizes thermal conditions of the Kola megablock in the Late Archaean that complies with the initial stage of the Baltic shield formation.
(in Russian, стр.17, fig. 15, tables. 1, ref 26, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 2
Astrakhantsev Yu.G., Guberman D.M., Diakonov B.P., Pevzner S.L., Troyanov A.K., Yakovlev Yu.N.
Geoacoustic noises in the Kola Superdeep Borehole
The intrusive body of rhyodacitic porphyry having a thickness about 110 m was fixed in the section of the Early Proterozoic Pechenga Complex of the Kola Superdeep Borehole (SG-3) in an interval of 4673.0-4831.6 m. Rhyodacites correspond to the hypersthene-normative calc-alkalic rocks with normal alkalinity oversaturated by Al2O3 and enriched by Fe and Mg. On a set of ore-minerals (oxides – magnetite, ilmenite, hematite, rutile; sulfides – chalcopyrite, pyrite, pyrrhotite, millerite, zygenite) rhyodacites are close to the host-volcanites of the Orshoaivi-Pirttijarvi Suite and host-sediments of the Luchlompolo Suite, but they differ by stability of chemical composition and by deficiency of isomorphic admixtures. They have a high natural radioactivity, which is caused by the increased contents of U and especially Th. U-Pb age of zircones from rhyodacites – 2043+/–18 Ma. Probably, their introduction preceded formation of the Ni-bearing gabbro-wehrlitic intrusives of the Pechenga Area.
(in Russian, стр.5, fig. 6, tables. 0, ref 6, Adobe PDF, Adobe PDF 0 Kb)
Vol. 10 (2007 year), No. 2
Guberman D.M., Badalov O.G., Pevzner S.L., Khmelinsky V.I., Yudin E.I., Yakovlev Yu.N.
Monitoring of geofields in the Kola Superdeep geolaboratory: History, experience, basic challenges and results
The results for investigation of geoacoustic noises distribution in a range of 100-5000 Hz along the Kola Superdeep Borehole (SG-3) have been discussed. A geological section cut by the borehole in the interval of 300-6840 m is shown to be dynamically active by parameters of three-component measurements of geoacoustic noises (GAN). When comparing the data obtained at a year intervals, we found a vertical migration of zones of the stressed state of rocks that is fixed by appearance of new GAN local anomalies or disappearance of those found earlier. From the analysis of the GAN amplitude-frequency spectra, gas emission from the rock massif has been observed, in particular, at the zones of tectonic dislocation of the geological environment.
(in Russian, стр.8, fig. 0, tables. 6, ref 6, 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)