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21.
N. G. Razzhigaeva L. A. Ganzei T. A. Grebennikova L. M. Mokhova T. A. Kopoteva A. V. Rybin A. A. Kharlamov 《Russian Journal of Pacific Geology》2009,3(6):570-584
The results of the complex study of a Holocene peat bog in the southern part of Ketoi Island, which is proposed to serve as
a reference section for the Central Kuriles, are discussed. The peat bog’s stratigraphy is based on botanic, palynological,
and diatom data, 16 radiocarbon age determinations, and the composition of the volcanic ashes. The peat accumulation initiated
approximately 6500 years ago. The successive changes of the island’s vegetation are traced through the Middle-Late Holocene
with defining of the phases of its development and dating the paleolandscape transformations related to the climatic oscillations
and volcanic eruptions. 相似文献
22.
Klementiev A. M. Khatsenovich A. M. Bazargur D. Tserendagva Y. Marchenko D. V. Rybin E. P. Gunchinsuren B. Olsen J. W. Krivoshapkin A. I. 《Doklady Earth Sciences》2023,507(3):S420-S423
Doklady Earth Sciences - Here, we report a fragmentary Castor fiber (Linnaeus, 1758) proximal left ulna from Tsagaan Agui Cave (Gobi Altai Mountains, southern Mongolia). This constitutes the first... 相似文献
23.
A. K. Rybin M. G. Leonov E. S. Przhiyalgovskii V. Yu. Batalev E. A. Bataleva V. D. Bragin Yu. A. Morozov G. G. Schelochkov 《Doklady Earth Sciences》2016,470(1):968-971
We studied the infrastructure of granite massifs of the Central Tien Shan and its correlation with the electric conductive layer of the upper crust, which made possible to reveal new peculiarities of the structure of the granite layer in the region and to clarify the nature of low resistivity layers. 相似文献
24.
ANDREAS DEHNERT FRANK PREUSSER JAN D. KRAMERS NAKI AKÇAR PETER W. KUBIK REGINA REBER CHRISTIAN SCHLÜCHTER 《Boreas: An International Journal of Quaternary Research》2010,39(3):620-632
Dehnert, A., Preusser, F., Kramers, J. D., Akçar, N., Kubik, P. W., Reber, R. & Schlüchter, C. 2010: A multi‐dating approach applied to proglacial sediments attributed to the Most Extensive Glaciation of the Swiss Alps. Boreas, Vol. 39, pp. 620–632. 10.1111/j.1502‐3885.2010.00146.x. ISSN 0300‐9483. The number and the timing of Quaternary glaciations of the Alps are poorly constrained and, in particular, the age of the Most Extensive Glaciation (MEG) in Switzerland remains controversial. This ice advance has previously been tentatively correlated with the Riss Glaciation of the classical alpine stratigraphy and with Marine Isotope Stage (MIS) 6 (186–127 ka). An alternative interpretation, based on pollen analysis and stratigraphic correlations, places the MEG further back in the Quaternary, with an age equivalent to MIS 12 (474–427 ka), or even older. To re‐evaluate this issue in the Swiss glaciation history, a multi‐dating approach was applied to proglacial deltaic ‘Höhenschotter’ deposits in locations outside the ice extent of the Last Glacial Maximum. Results of U/Th and luminescence dating suggest a correlation of the investigated deposits with MIS 6 and hence with the Riss Glaciation. Cosmogenic burial dating suffered from large measurement uncertainties and unusually high 26Al/10Be ratios and did not provide robust age estimates. 相似文献
25.
Yu. A. Martynov A. I. Khanchuk J. -I. Kimura A. V. Rybin A. Yu. Martynov 《Petrology》2010,18(5):489-513
Newly obtained precise analytical data on trace elements and radiogenic Sr, Nd, and Pb isotopes testify to anomalous geochemical
characteristics of mafic and intermediate Quaternary lavas in Paramushir (in the north of the Kuril arc), Kunashir and Iturup
(in the south) islands, which are the largest three islands of the Kuril island arc. The high K and LREE concentrations in
the volcanic products in Paramushir Island resulted from the southward expansion of the mantle thermal anomaly of the Kamchatka
Peninsula and the involvement of melts related to the melting of oceanic sediments in magma generation. The depleted characteristics
of the mafic volcanics are explained by the relatively young tectono-magmatic events during the opening of the Kuril backarc
basin. The Kuril island-arc system developed on a heterogeneous basement. The northern islands are a continuation of the volcanic
structures of southern Kamchatka, which were formed above an isotopically depleted and hot lithospheric mantle domain of composition
close to that of the Pacific MORB type. The southern islands were produced above an isotopically enriched and cold lithospheric
domain of the Indian-Ocean MORB type, which was modified in relation to relatively young backarc tectono-magmatic processes.
Although issues related to the genesis of the transverse geochemical zoning were beyond the originally formulated scope of
our research, the homogeneous enough isotopic composition of the rear-arc lavas in the absence of any mineralogical and geochemical
lines of evidence of crustal contamination suggests an independent magmatic source. 相似文献
26.
STEFANO ANDREUCCI MARK D. BATEMAN CLAUDIO ZUCCA SELIM KAPUR İHSAN AKŞIT ADAM DUNAJKO VINCENZO PASCUCCI 《Sedimentology》2012,59(3):917-938
A multi‐disciplinary approach was followed to investigate two thick palaeosol strata that alternate with wind‐blown dominated deposits developed along the Alghero coast (North‐west Sardinia, Italy). Optically stimulated luminescence ages reveal that both palaeosols were developed during cooler drier periods: the first one at around 70 ka Marine Isotope Stage 4 and the latter around 50 ka (Marine Isotope Stage 3). In contrast, the pedological features indicate that the palaeosols underwent heavy weathering processes under warm humid to sub‐humid conditions, characteristic of the Sardinian climate during the last interglacial stage (Marine Isotope Stage 5e). To reconcile this apparent data discrepancy, a range of sedimentological and pedological analyses were conducted. These analyses reveal that the palaeosols possess a complex history, with accumulation and weathering occurring during Marine Isotope Stage 5e, and erosion, colluviation and final deposition taking place during the following cold stages. Thus, even if these reddish palaeosols were last formed during the glacial period, the sediments building up these strata probably record the climate of the last interglacial stage (Marine Isotope Stage 5e). Trace element and X‐ray diffraction analyses, together with scanning electron microscope images, reveal the presence of Saharan dust in the parent material of the palaeosols. However, no evidence of any far‐travelled African dust has been observed in the Marine Isotope Stage 4–3 aeolian deposits. It is possible to conclude that in the West Mediterranean islands, Saharan dust input, even if of modest magnitude, is preserved preferentially in soils accumulated and weathered during interglacial stages. 相似文献
27.
Levin B. W. Rybin A. V. Vasilenko N. F. Prytkov A. S. Chibisova M. V. Kogan M. G. Steblov G. M. Frolov D. I. 《Doklady Earth Sciences》2010,435(1):1507-1510
In June 2009, one of the greatest eruptions of the Sarychev Peak volcano in Matua Island (48°06′ N, 153°12′ E) for the recent
historical period occurred. With the help of satellite sounding methods, the first signs of volcanic activity were recorded
and all the stages of the explosive eruption were traced. During the expeditionary investigations in the active volcano, unique
data on the character of the eruption were obtained. The volume of erupted material was 0.4 cubic km, which lead to an increased
area of Matua Island by 1.4 square km. The GPS observation station set at the distance of 7 km from the volcano recorded the
rapid displacement of the Earths’s surface during the first two days of the active phase of eruption. This eruption of the
Sarychev Peak volcano occurred 2.5 years after the catastrophic Simushir earthquakes in the period of intensive relaxation
of stresses in the middle of the central part of the Kurile island arc. 相似文献
28.
Alexey Y. Martynov Jun-Ichi Kimura Yuri A. Martynov Alexsander V. Rybin 《Island Arc》2010,19(1):86-104
Middle Miocene to Quaternary lavas on Kunashir Island in the southern zone of the Kurile Arc were examined for major, trace, and Sr–Nd–Pb isotope compositions. The lavas range from basalt through to rhyolite and the mafic lavas show typical oceanic island arc signatures without significant crustal or sub-continental lithosphere contamination. The lavas exhibit across-arc variation, with increasingly greater fluid-immobile incompatible element contents from the volcanic front to the rear-arc; this pattern, however, does not apply to some other incompatible elements such as B, Sb, and halogens. All Sr–Nd–Pb isotope compositions reflect a depleted source with Indian Ocean mantle domain characteristics. The Nd and Pb isotope ratios are radiogenic in the volcanic front, whereas Sr isotope ratios are less radiogenic. These Nd isotope ratios covary with incompatible element ratios such as Th/Nd and Nb/Zr, indicating involvement of a slab-derived sediment component by addition of melt or supercritical fluid capable of mobilizing these high field-strength elements and rare earth elements from the slab. Fluid mobile elements, such as Ba, are also elevated in all basalt suites, suggesting involvement of slab fluid derived from altered oceanic crust. The Kurile Arc lavas are thus affected both by slab sediment and altered basaltic crust components. This magma plumbing system has been continuously active from the Middle Miocene to the present. 相似文献
29.
A. V. Degterev A. V. Rybin I. V. Melekestsev N. G. Razzhigaeva 《Russian Journal of Pacific Geology》2012,6(6):423-432
The first results of tephrochronological studies of the Sarychev Peak volcano on Matua Island in the Central Kuril Islands are presented and the eruptive evolution of the volcano in the Holocene is reconstructed. The volcanic products are typified and the general style of their geochemical evolution is reviewed on the basis of the distribution of the petrogenic oxides and trace elements in tephra samples taken bed-by-bed from the reference section of the soil-pyroclastic cover on Matua Island. The horizons of transit ashes are identified. 相似文献
30.