Ingression of the Aral Sea water to southern west Siberia in the Holocene: Paleontological evidence and chronology     

S. A. Gusskov  A. V. Kanygin  Ya. V. Kuzmin  G. S. Burr  A. J. T. Jull  L. B. Khazin 《Doklady Earth Sciences》2008,418(1):24-27

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Dynamics of mammoth (<Emphasis Type="Italic">Mammuthus primigenius</Emphasis> Blum.) populations of Asia and North America and its correlation with climatic changes in the Late Neopleistocene (45 000–9700 years BP)     

Ya. V. Kuzmin  L. A. Orlova  V. N. Dementiev 《Doklady Earth Sciences》2008,421(2):978-982

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The first radiocarbon dates on foraminifera shells from the Karginian marine sediments of the Taimyr Peninsula (Northern Central Siberia) and their interpretation     

S. A. Gusskov  Ya. V. Kuzmin  L. K. Levchuk  G. S. Burr 《Doklady Earth Sciences》2008,421(2):902-904

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First data on the environment and climate change within the Zhom-Bolok volcanic field (Eastern Sayan Mountains) in the Middle–Late Holocene     

E. V. Bezrukova  A. A. Shchetnikov  M. I. Kuzmin  O. G. Sharova  N. V. Kulagina  P. P. Letunova  E. V. Ivanov  M. A. Kraynov  E. V. Kerber  I. A. Filinov  O. V. Levina 《Doklady Earth Sciences》2016,468(1):527-531

This paper considers the results of comprehensive lithological, biostratigraphic, and geochemical investigation of sediments in Khara-Nur Lake (Eastern Sayan Mountains) situated in the area of the greatest Holocene eruptions in the Central Asia Region. The age of the basal sediment layer is estimated at 6881 ± 53 years. The local natural environment and climate have undergone great changes since that time. The Holocene volcanic events did not exert a catastrophic impact on the regional landscape, but they caused dramatic changes in the local vegetation. The well-defined correlation of the regional events with the well-known records of the natural environment in the Northern Hemisphere is indicative of the decisive influence of global atmospheric circulation on restructuring the landscape and climate system in the Zhom-Bolok Region in the Middle–Late Holocene.  相似文献   

Peculiarities of the composition of volatile components in picroilmenites from Yakutian kimberlites of various ages (by gas chromatography—mass spectrometry)     

A. A. Tomilenko  T. A. Bul’bak  L. N. Pokhilenko  D. V. Kuzmin  N. V. Sobolev 《Doklady Earth Sciences》2016,469(1):690-694

The composition of volatile components in picroilmenites from Yakutian kimberlitic pipes of various ages (the Olivinovaya, Malokuonapskaya, and Udachnaya–East pipes) was studied for the first time by means of gas chromatography–mass spectrometry (GC-MS). It was shown that picroilmenites and olivines from same kimberlitic pipes contained volatile components of close composition, whereas these components were quite different in these minerals from different pipes. These features point to a common source and represent the specificity of the magma chamber formed under the pronounced influence of hydrocarbons with their derivates, as well as nitrogen-, chlorine-, and sulfur-containing compounds. The fraction of hydrocarbons and derivates in the composition of volatile matter is as high as 99%, including 9.7% of chlorine- and fluorinecontaining compounds.  相似文献   

Holes in the spinous processes of woolly mammoth vertebrae: spatial and temporal distribution,and the causes of pathology formation     

Sergey V. Leshchinskiy  Yaroslav V. Kuzmin  Mathieu Boudin  Leeli Amon 《第四纪科学杂志》2021,36(7):1254-1267

The latest data on holes in the spinous processes of the vertebrae of woolly mammoths, a rare pathology, are presented. This was identified at 19 sites of northern Eurasia. Such destructive changes are recorded ca. 34–12k ¹⁴C a bp , and only two sites dated to >50k and >41k ¹⁴C a bp. The main hypotheses about hole formation are: vertebral abnormalities; bone infections; genetic traits; and unfavourable geochemical environment. The pathology occurred in mammoths of all age groups, and could have arisen at the embryonic stage. There are two types: classic holes associated with osteolytic changes; and very rarely tumour-like lesions. The most likely cause of the lesions is alimentary osteodystrophy caused by chronic mineral starvation. The aetiology of this disease is usually associated with a deficiency or excess of macro- and microelements in the geochemical landscape, and through forage and water this leads to a severe metabolic disorder. Analysis of palaeopathological data shows two waves of geochemical stress in animals, ca. 26–18k and ca. 16–12k ¹⁴C a bp. Therefore, the woolly mammoth extinction can be viewed as a non-linear function, with two peaks of high mortality corresponding to the Last Glacial Maximum and the Lateglacial.  相似文献   

The First Reconstructions of Vegetation and Climate Changes in the Central Part of the Oka Plateau (East Sayan Mountains) in the Middle–Late Holocene     

Bezrukova  E. V.  Reshetova  S. A.  Volchatova  E. V.  Kuzmin  M. I. 《Doklady Earth Sciences》2022,506(1):687-692

Doklady Earth Sciences - The Central part of the Oka Plateau lying in the East Sayan Mountains is still a poorly studied area of southern Siberia as regards its paleogeography. This gap can be...  相似文献   

Correlation of the Late Cenozoic endogenic events and climatic variations in Central Asia     

V. V. Yarmolyuk  M. I. Kuzmin 《Stratigraphy and Geological Correlation》2006,14(2):105-125

Trend of climatic changes in geological history of the Earth was determined by gradual decrease in the global surface temperature. Substantial deviations from this trend depended on the prevalent type of volcanism: predominantly explosive volcanism at convergent boundaries between lithospheric plates led to cooling and onset of glacial epochs, while intense intraplate volcanism strengthened greenhouse effect and resulted in global warming. During cold epochs, orogenic processes played an important role in climatic variations. The most frequent and regular climatic variations are controlled by the Earth position in solar orbit (Milankovitch cycles). The Late Cenozoic variations of cold climate were interrelated with orogenic processes caused by collision between the Indian and North Asian lithospheric plates. The first event of considerable cooling in the Northern Hemisphere (2.8–2.5 Ma ago) coincided with a rapid growth of mountains throughout the collision belt. The Tibetan Plateau formed in South Asia. In Central Asia, the large (> 1.5 × 10⁶ km²) Khangai-Altai-Sayan mountain system appeared 3 Ma ago. Total area subjected to orogenic processes in Central and South Asia exceeded 9 × 10⁶ km². The intense intraplate volcanism suggests that sublithospheric mantle was involved into orogenic processes. Alternation of glacial and interglacial climatic epochs during the last 1.8 m.y. is recorded in Central Asia. These climatic variations are compatible with the Milankovitch cycles. As is established, climatic events recognizable in the Baikal sedimentary record are correlative with interglacial and glacial epochs detectable in volcanic lavas of the East Sayan Mountains. There are indications of lava eruptions into ice during the cold periods. It is assumed therefore that all the cooling epochs detectable in the Baikal sedimentary record after 1.8 Ma were associated with development of mountain glaciation that formed glacial sheet up to 3 km thick and 100 000 km² in size. During the Brunhes Chron, there were eight glaciations at least. The endogenic (volcanism and orogeny) and exogenic (glaciation) processes during the last 3 m.y. are shown to be correlative. The intermittent development and degradation of thick ice sheets was responsible for oscillation of lithospheric load on the asthenosphere, and this caused periodical magma generation in marginal parts of volcanic provinces.  相似文献   

Frequency dependence of the scattering pulse broadening for the Crab pulsar     

A. D. Kuzmin  V. I. Kondrat’ev  S. V. Kostyuk  B. Ya. Losovsky  M. V. Popov  V. A. Soglasnov  N. D’Amico  S. Montebugnoli 《Astronomy Letters》2002,28(4):251-256

We measured the frequency dependence of the pulsar pulse broadening by scattering over a wide frequency range, from 40 to 2228 MHz, based on direct measurements of this parameter using giant pulses from the pulsar PSR B0531+21 in the Crab Nebula. Our measurements were carried out at the following seven frequencies: 40, 60, and 111 MHz at the Pushchino Radio Astronomy Observatory (Astrospace Center, Lebedev Physical Institute, Russian Academy of Sciences), 406 MHz at the Medicina Observatory (Instituto di Radioastronomia, Italy), and 594, 1430, and 2228 MHz at the Kalyazin Radio Astronomy Observatory (Astrospace Center, Lebedev Physical Institute, Russian Academy of Sciences). The measured frequency dependence of the pulse broadening by scattering τ_SC (υ) ? υ^γ, where γ=?3.8±0.2, agrees with a model Gaussian distribution of interstellar inhomogeneities (γ=?4) but falls outside the error limits of correspondence to a Kolmogorov model spectrum of inhomogeneities (γ=?4.4).  相似文献   

Upward high-energy field-aligned electron beams above the polar edge of auroral oval: observations from the SKA-3 instruments onboard the Auroral Probe (Interball-2)     

V. A. Stepanov  Y. I. Galperin  A. K. Kuzmin  F. K. Shuiskaya  L. S. Gorn  B. A. Ilyin  M. V. Iovlev  A. A. Klimashov  I. I. Cherkashin  B. I. Khazanov  A. Y. Safronov 《Annales Geophysicae》1998,16(9):1046-1055

A new phenomenon was found at the polar edge of the auroral oval in the postmidnight-morning sectors: field-aligned (FA) high-energy upward electron beams in the energy range 20–40 keV at altitudes about 3 R_E, accompanied by bidirectional electron FA beams of keV energy. The beam intensity often reaches more than 0.5 · 10³ electrons/s · sr · keV · cm², and the beams are observed for a relatively long time (3 10²–10³ s), when the satellite at the apogee moves slowly in the ILAT-MLT frame. A qualitative scenario of the acceleration mechanism is proposed, according to which the satellite is within a region of bidirectional acceleration where a stochastic FA acceleration is accomplished by waves with fluctuating FA electric field components in both directions.  相似文献