Carbonate mineralogy of lake Hovsgol sediments: Water balance and paleoclimatic conditions   总被引：1，自引：0，他引：1  

E. P. Solotchina  M. I. Kuzmin  V. N. Stolpovskaya  A. A. Prokopenko  P. A. Solotchin 《Doklady Earth Sciences》2008,419(2):438-443

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A 640 kyr geomagnetic and palaeoclimatic record from Lake Baikal sediments     

Vadim A. Kravchinsky  Michael E. Evans  John A. Peck  Hideo Sakai  Mikhail A. Krainov  John W. King  Mikhail I. Kuzmin 《Geophysical Journal International》2007,170(1):101-116

Magnetic remanence vectors for 1737 samples from two ∼100 m cores of Lake Baikal sediments are reported along with complete magnetic susceptibility profiles obtained from a pass-through system. Chronological control is established by means of two independent correlations; first, by matching susceptibility variations to the oceanic oxygen isotope record and second, by matching the relative palaeointensity variations to the SINT-800 global reference curve. These both imply an average deposition rate of 15 cm kyr^–1 and a basal age of ∼640 ka. Spectral analysis reveals the presence of Milankovitch signals at ∼100 kyr (eccentricity), ∼41 kyr (obliquity) and ∼23 and ∼19 kyr (precession). Stable remanence vectors are almost all of normal polarity. The few exceptions comprise brief intervals of low and/or negative inclinations which probably represent geomagnetic excursions. However, these are far less numerous than the high sedimentation rate would lead one to expect. Furthermore, only four of them can be readily matched to the—still poorly understood—global pattern. These are the Laschamp, the Albuquerque, the Iceland Basin and perhaps the West Eifel excursions which occurred at ∼38 000, ∼146 000, at 180 000–190 000 and at 480 000–495 000 yr ago, respectively.  相似文献   

Sedimentation processes and new age constraints on rifting stages in Lake Baikal: results of deep-water drilling     

M. I. Kuzmin  E. B. Karabanov  A. A. Prokopenko  V. F. Gelety  V. S. Antipin  D. F. Williams  A. N. Gvozdkov 《International Journal of Earth Sciences》2000,89(2):183-192

 With this paper we present a first attempt to combine the direct results on lithology, composition and age dating in the boreholes BDP-93, BDP-96 and BDP-97 with geological and seismic data from the areas where those sections were drilled. The sedimentary environments represented by the BDP boreholes are markedly different and possess characteristic lithological features. The results of the deep drilling provide the essential means for testing numerous age models used in geological reconstructions of the Lake Baikal rifting dynamics. Neither the basin-wide unconformity interpreted from seismic data, nor the interpreted change from shallow-water to deep-water facies at the boundary of the seismic stratigraphic complexes were found in the BDP-96 boreholes on Academician Ridge. Also, lithology does not support the proposed reconstructions of intense lake level fluctuations and transgressions during the Pliocene at Academician Ridge. The continuous deep-water hemipelagic sedimentation at Academician Ridge has existed for the past 5 Ma. The beginning of an intense rifting phase of the Neobaikalian sub-stage and related drastic changes in sedimentation processes were interpreted on seismic sections as the basin-wide unconformity B10. Different age estimates for this boundary ranged from Late Pliocene (3.5 Ma) to Plio-Pleistocene boundary. As shown by BDP-96 borehole, B10 is associated with a lithological change from diatomaceous ooze to dense silty clay and not with an erosional contact. The new age for this boundary in BDP-96 is approximately 2.5 Ma. This new age constraint suggests that the upper sedimentary strata of Northern Baikal (1.5–1.7 km thick) have formed during the past 2.5 Ma with average sedimentation rates of 60–70 cm/ka. The BDP-93 boreholes at Buguldeika suggest that uplift in Primorsky Range took place prior to 1.07–1.31 Ma, a date which exceeds the age of previous geological models. Received: 12 March 1999 / Accepted: 10 February 2000  相似文献   

Low-frequency flux-density measurements and spectral features of millisecond pulsars     

A. D. Kuzmin  B. Ya. Losovsky 《Astronomy Letters》2000,26(8):500-505

Radio flux-density measurements for a large sample of millisecond pulsars at a low frequency of 102 MHz are presented. Using higher frequency measurements, we construct their spectra in the frequency range from 102 MHz to 4.8 GHz, the widest one studied to date. The spectra of millisecond and normal pulsars have been found to differ. The spectra of millisecond pulsars have no low-frequency turnover typical of normal pulsars. The absence of a low-frequency turnover in the spectrum suggests that the emitting regions of millisecond and normal pulsars differ in geometry, which we interpret by deviation of the magnetic field from a dipole one or by compactness of the emitting region.  相似文献   

Analysis of the Results of Deformation Monitoring by the Inclinometer System at the Vladimir Filanovsky Field     

Kuzmin  Yu. O.  Deshcherevskii  A. V.  Fattakhov  E. A.  Kuzmin  D. K.  Kazakov  A. A.  Aman  D. V. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(11):1659-1666

Izvestiya, Atmospheric and Oceanic Physics - The system of geodynamic monitoring at the Vladimir Filanovsky oil and gas condensate field is presented. The technologies for data transfer to the...  相似文献   

Determination of Reference Values for NIST SRM 610–617 Glasses Following ISO Guidelines     

Klaus Peter Jochum  Ulrike Weis  Brigitte Stoll  Dmitry Kuzmin  Qichao Yang  Ingrid Raczek  Dorrit E. Jacob  Andreas Stracke  Karin Birbaum  Daniel A. Frick  Detlef Günther  Jacinta Enzweiler 《Geostandards and Geoanalytical Research》2011,35(4):397-429

We present new reference values for the NIST SRM 610–617 glasses following ISO guidelines and the International Association of Geoanalysts’ protocol. Uncertainties at the 95% confidence level (CL) have been determined for bulk‐ and micro‐analytical purposes. In contrast to former compilation procedures, this approach delivers data that consider present‐day requirements of data quality. New analytical data and the nearly complete data set of the GeoReM database were used for this study. Data quality was checked by the application of the Horwitz function and by a careful investigation of analytical procedures. We have determined quantitatively possible element inhomogeneities using different test portion masses of 1, 0.1 and 0.02 μg. Although avoiding the rim region of the glass wafers, we found moderate inhomogeneities of several chalcophile/siderophile elements and gross inhomogeneities of Ni, Se, Pd and Pt at small test portion masses. The extent of inhomogeneity was included in the determination of uncertainties. While the new reference values agree with the NIST certified values with the one exception of Mn in SRM 610, they typically differ by as much as 10% from the Pearce et al. (1997) values in current use. In a few cases (P, S, Cl, Ta, Re) the discrepancies are even higher.  相似文献   

High temporal resolution observations of the pulsar microstructure at 102 MHz     

A. D. Kuzmin  P. A. Hamilton  Yu. P. Shitov  P. M. McCulloch  D. McConnell  V. D. Pugatchev 《Monthly notices of the Royal Astronomical Society》2003,344(4):1187-1192

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Regions of Potential Existence of Free Water (Ice) in the Near-Surface Martian Ground: Results from theMars OdysseyHigh-Energy Neutron Detector (HEND)     

R. O. Kuzmin  E. V. Zabalueva  I. G. Mitrofanov  M. L. Litvak  W. V. Boynton  R. S. Saunders 《Solar System Research》2004,38(1):1-11

We report results of the analysis of the data on global mapping of neutron fluxes from the Martian surface, which have been obtained during the first ten months of measurements carried out by the Russian high-energy neutron detector HEND mounted aboard the AmericanMars Odysseyorbiter. This analysis allowed us to separate regions where free water (in ice form) prevailed in the surface layer (with a thickness of up to 2 m) of the Martian ground from regions where physically and chemically bound ground water was most likely to be the dominant form of water. The global mapping of regions with increased ice content in the ground-surface layer revealed a direct correlation with regions of polygonal terrains morphologically similar to terrestrial polygonal forms of permafrost origin. The potential content of bound water forms in the ground of circumpolar areas of the planet is also estimated.  相似文献   

Mineralogical Indicators of Climate Changes in Southwestern Siberia in Holocene Sediments of Bolshie Toroki Lake     

Solotchina  E. P.  Kuzmin  M. I.  Solotchin  P. A.  Maltsev  A. E.  Leonova  G. A.  Krivonogov  S. K. 《Doklady Earth Sciences》2021,496(1):17-23

Doklady Earth Sciences - We present the results of studying the Holocene sediments of Bolshie Toroki Lake, a shallow brackish lake with carbonate sedimentation and high bioproductivity, located in...  相似文献   

Ophiolitic Complex of the Matachingai River on Eastern Chukotka: Fragment of Lithosphere in Mesozoic Back-Arc Basin     

G. V. Ledneva  B. A. Bazylev  A. V. Moiseev  S. D. Sokolov  A. Ishiwatari  D. V. Kuzmin  B. V. Belyatsky 《Geotectonics》2018,52(4):447-467

The Matachingai River basin is known among the few ophiolitic complexes on eastern Chukotka as the southern boundary of the Chukotka Fold System (in terms of tectonics, the Chukotka microcontinent or a fragment of the Arctic Alaska–Chukotka microplate). This complex comprises tectonic blocks of residual spinel harzburgite with dunite bodies and pyroxenite, olivine gabbro, and leucogabbro veins; blocks of hornblende gabbro, diorite, and plagiogranite; and Upper Jurassic–Lower Cretaceous basaltic–cherty and cherty–carbonate rocks. The geological relationships of rocks within tectonic blocks, the compositions of primary minerals, the bulk geochemistry of rocks, as well as the strontium, neodymium, and lead isotopic compositions, make it possible to consider individual tectonic blocks of the complex as fragments of a disintegrated oceanic-type lithosphere that formed in a back-arc spreading center. The melts, crystallization products of which are represented by hornblende gabbro of blocks, olivine gabbro of veins, and basalts, separated from geochemically and isotopically heterogeneous mantle. Blocks composed of rocks with various modal composition are likely relicts of an oceanic lithosphere of different segments of a back-arc basin. The studied complex may be a lithosphere of one of the Middle–Late Jurassic back-arc basins. Fragments of these basins are retained in ophiolitic complexes on Great Lyakhovsky Island of the New Siberian Islands Archipelago, western Chukotka, and the Brooks Range in Alaska.  相似文献