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Environmental changes in the northern Altai during the last millennium documented in Lake Teletskoye pollen record 总被引：1，自引：0，他引：1
Andrei A. Andreev Roberto Pierau Ivan A. Kalugin Andrei V. Daryin Lyubov G. Smolyaninova Bernhard Diekmann 《Quaternary Research》2007,67(3):394-399
A high-resolution pollen record from Lake Teletskoye documents the climate-related vegetation history of the northern Altai Mountain region during the last millennium. Siberian pine taiga with Scots pine, fir, spruce, and birch dominated the vegetation between ca. AD 1050 and 1100. The climate was similar to modern. In the beginning of the 12th century, birch and shrub alder increased. Lowered pollen concentrations and simultaneous peaks in herbs (especially Artemisia and Poaceae), ferns, and charcoal fragments point to colder and more arid climate conditions than before, with frequent fire events. Around AD 1200, regional climate became warmer and more humid than present, as revealed by an increase of Siberian pine and decreases of dry herb taxa and charcoal contents. Climatic conditions were rather stable until ca. AD 1410. An increase of Artemisia pollen may reflect slightly drier climate conditions between AD 1410 and 1560. Increases in Alnus, Betula, Artemisia, and Chenopodiaceae pollen and in charcoal particle contents may reflect further deterioration of climate conditions between AD 1560 and 1810, consistent with the Little Ice Age. After AD 1850 the vegetation gradually approached the modern one, in conjunction with ongoing climate warming. 相似文献
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A. S. Astakhov V. A. Akulichev A. V. Dar’in I. A. Kalugin Yanguang Liu V. V. Babich A. A. Bosin E. G. Vologina V. V. Plotnikov 《Doklady Earth Sciences》2018,480(2):767-772
For the first time, the reconstruction of variations in the duration over several hundred years was conducted on the basis of models developed by comparing hydrometeorological observations and detailed scanning of the chemical composition of bottom sediments accumulated during the corresponding period. The gauge models for the reconstruction of air temperature and ice cover of the water area for three sites in the northern part of the Chukchi Sea have been developed. During the reconstruction, an insignificant increase in the duration of the ice-free period during the Little Ice Age was established, which does not coincide with the changes in the temperature regime that took place. It is concluded that the dynamics of the inflow of warm Pacific waters through the Bering Strait had the predominant influence on the ice regime of the Chukchi Sea. 相似文献
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Doklady Earth Sciences - In the taxitic gabbro-dolerites of the upper contact zone of the Norilsk-1 intrusion, five boron minerals were found: kotoite Mg3(BO3)2, suanite Mg2B2O5, warwickite... 相似文献
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L. V. Zamana A. B. Ptitsyn G. Chu S. A. Reshetova A. V. Dar’in I. A. Kalugin 《Doklady Earth Sciences》2011,437(1):335-339
On the basis of bottom sediment core dating performed by the technogenic isotope 137Cs, the rate of sedimentation in periodically drying Zun-Torei Lake (water area is up to 300 km2) is estimated at 2.88 mm per year over the last 59 years. This value is in agreement with the data of palinological determinations
(3.44 mm per year). High sedimentation rates are attributed to intensive evaporite sedimentation and probable eolian addition
of terrigenous material. 相似文献
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T. Oyunchimeg A.E. Izokh A.V. Vishnevsky V.M. Kalugin 《Russian Geology and Geophysics》2009,50(10):863-872
Platinum group element (PGE) mineral assemblage has been discovered in the gold placers along the Burgastain Gol and Iljgen Gol (Western Mongolia). It includes isoferroplatinum (Pt3Fe) grains with inclusions of cooperite (PtS), laurite-erlichmanite (RuS2-OsS2), cuprorhodsite-malanite (CuRh2S4-CuPt2S4), irarsite-hollingworthite (IrAsS-RhAsS), and bowieite (Rh2S3).It has been established that the isoferroplatinum assemblage was generated from a volcanoplutonic picrite complex in the Ureg Nuur area, which is widespread in the central part of the Harhiraa accretionary terrane. According to composition, the PGE mineral–Cr-spinel assemblage was referred to as the Ural-Alaskan type. 相似文献
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Babich V. V. Darin A. V. Smolyaninova L. G. Kalugin I. A. 《Doklady Earth Sciences》2017,477(2):1470-1472
Decomposition of five different paleoclimatic reconstructions of regional and hemispheric scale into different frequency periodic components has been performed for the extratropical zone of the Northern Hemisphere using spectral analysis methods (Hilbert–Huang transformation, wavelet transform, Fourier transform). The presence of ~1000, ~500, ~350, and ~200-year quasi-cyclic periodicities has been established, which determines climatic variability over the last 2–4 millennia. The presence of similar cyclicities, manifested in climatic and other geological processes, has been noted by many researchers and has been explained, as a rule, by changes in solar insolation. Thus, there is every reason to believe that the revealed quasi-periodic components in the climate variability of the extratropical zone of the Northern Hemisphere are natural, conditioned by natural cyclical phenomena and can serve as a basis for long-term predictive climatic constructions.
相似文献17.
Rogozin D. Y. Darin A. V. Kalugin I. A. Melgunov M. S. Meydus A. V. Degermendzhi A. G. 《Doklady Earth Sciences》2017,476(2):1226-1228
Doklady Earth Sciences - We estimated the age and sedimentation rate of bottom sediments in Cheko Lake located in southern Evenkia, in the territory of Tunguska Nature Reserve, near the supposed... 相似文献
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The runoff of the Selenga R., the largest tributary of Lake Baikal, in recent two decades corresponds to a low-water period. Such decrease can be due to the global climate processes, which have an effect on the amounts of precipitation onto and evaporation from Selenga drainage basin, which is located in arid climate zone. The adaptation of Ecomag software complex to simulating river runoff in the Selenga Basin based on global databases (relief, soils, vegetation, and weather information) is described. The model was calibrated and verified, and the statistical estimates of calculation efficiency were constructed. The obtained model of runoff formation in the Selenga Basin was used to assess the possible changes in the climate and water regime in the XXI century with the use of data of global climate models under different scenarios of greenhouse gas emissions. Throughout the XXI century, the Selenga R. runoff may decrease by 10–40%, depending on the forecasted climate conditions. 相似文献
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E.G. Vologina I.A. Kalugin Yu.N. Osukhovskaya M. Sturm N.V. Ignatova Ya.B. Radziminovich A.V. Dar&#x;in M.I. Kuz&#x;min 《Russian Geology and Geophysics》2010,51(12):1275-1284
The paper presents the results of a comprehensive investigation into the recent sediments of Proval Bay. This bay formed during catastrophicflooding of a big block of land as a result of an earthquake in 1862. Comparison of the sketch map of the bay for 1862 with its modern mapshows that the boundary of the Selenga River delta has shifted considerably eastward. The sediments of Proval Bay are sands, silty pelite,and pelitic silt. Terrigenous material is predominant and consists of mineral grains and land plant remains, admixed with diatom frustules andsponge spicules. In the southwestern part of the bay, turbidites and a soil layer have been found. The latter was buried when the water levelin Lake Baikal rose after the construction of the Irkutsk dam in 1959–1964. In the northeastern part of the bay, a peatlike layer has beenfound in the bottom sediment core. It formed in Lake Beloe, which existed in the Tsagan steppe before the 1862 earthquake. According todiatom analysis, this lake was shallow and eutrophic. The sedimentation rates in different parts of Proval Bay differ greatly and directly dependon proximity to the Selenga River. Variations in the geochemical indicators which reflect the ratio of organic to clastic components in thebottom sediments of the bay are controlled by temperature and water level variations in Lake Baikal. 相似文献