554 Peraga—an asteroid with unusual polarization properties?     

K. A. Antonyuk  N. N. Kiselev 《Solar System Research》2012,46(1):54-56

This paper presents the results of polarization observations of asteroid 554 Peraga obtained with the UBVRI polarimeter using the 1.25 m telescope of the Crimean Astrophysical Observatory down to phase angles of 3.1°–16.6° from October to November 2006. The asteroid’s polarization phase curve is shown to have a negative branch with the parameters P _min = −1.7% and α_min = 8.4°, which is typical of C-type asteroids. However, these data contradict the results of Zellner and Gradie (1976) obtained in March 1975 that the reflected light from the asteroid’s surface is positively polarized, ≈1% at phase angles of 8°–10°. Since the asteroid’s ecliptic longitudes differ by 160°-145° for the two observation periods, we discuss the possibility that the two sets of observations refer to the asteroid’s two hemispheres with different polarimetric properties.  相似文献   

The northeastern boundary of the Siberian Craton and its formation peculiarities (derived from occurrences of early Cambrian and Devonian intraplate magmatism)     

A. I. Kiselev  V. V. Yarmolyuk  I. I. Kolodeznikov  K. K. Struchkov  K. N. Egorov 《Doklady Earth Sciences》2012,447(1):1252-1258

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U-Pb systematics of detrital zircons from the Serebryanka Group of the Central Urals     

A.?V.?MaslovEmail author  G.?M.?Vovna  V.?I.?Kiselev  Yu.?L.?Ronkin  M.?T.?Krupenin 《Lithology and Mineral Resources》2012,47(2):160-176

Based on the LA-ICP-MS data, detrital zircons from the tillite-type conglomerates of the Tanin Formation (Serebryanka Group) on the western slope of the Central Urals include approximately equal proportions of crystals with Neoarchean and Paleoproterozoic U-Pb ages. Therefore, we can assume that crystalline rocks of the basement beneath the eastern part of the East European Craton served as a provenance for aluminosilicate clastics in the initial Serebryanka period. Detrital zircons from sandstones of the Kernos Formation have the Meso-Neoarchean (∼15%), Paleoproterozoic (∼60%), and Mesoproterozoic (∼26%) age. Comparison of the obtained data with the results of the study of detrital zircons from Riphean and Vendian sandstones of the Southern Urals shows that the Riphean and Lower Vendian rocks are mainly represented by erosional products of Middle and Upper Paleoproterozoic crystalline rocks that constitute the basement of the East European Craton. In addition, a notable role belonged to older (Lower Proterozoic, Neoarchean and Mesoarchean) rock associations during the formation of the Serebryanka Group. The terminal Serebryanka time (Kernos Age) differed from its initial stage (Tanin Age) by the appearance of Mesoproterozoic complexes in provenances. According to available data, these complexes played an insignificant role in the formation of Riphean-Vendian rocks in the neighboring South Uralian segment. This implies a spatiotemporal diversity of clastic material sources for Upper Precambrian rocks in the western megazone of the Southern and Central Urals.  相似文献   

New U-Pb isotopic data on the age of metamorphic and igneous rocks of the western margin of the Selenga-Stanovoi orogenic belt     

A. S. Vakh  O. V. Avchenko  N. A. Goryachev  V. I. Gvozdev  V. I. Kiselev  V. G. Khomich  Yanchen Yang  Songqing Ye  Guobin Zhang 《Doklady Earth Sciences》2013,450(2):575-582

New data on the isotopic age of zircons from metamorphic and igneous rocks are given for the Berezitovoe and Kirovskoe deposits located in the eastern margin of the Selenga-Stanovoi orogenic belt. The zircons were studied with the LA-ICP-MS method in the State Key Laboratory of Continental Dynamics, Northwestern University, Sian, Shansi province, People’s Republic of China. The results allowed us to reveal three age epochs in formation of the eastern part of the Selenga-Stanovoi orogenic belt (1.87 Ga; 380–330 Ma; 138–125 Ma), which have significant importance for understanding of the geological structure of the south-eastern framework of the North Asian craton.  相似文献   

Mesoproterozoic (Grenville-age) terranes in the Kyrgyz North Tianshan: Zircon ages and Nd–Hf isotopic constraints on the origin and evolution of basement blocks in the southern Central Asian Orogen     

A. Kröner  D.V. Alexeiev  Y. Rojas-Agramonte  E. Hegner  J. Wong  X. Xia  E. Belousova  A.V. Mikolaichuk  R. Seltmann  D. Liu  V.V. Kiselev 《Gondwana Research》2013,23(1):272-295

The North Tianshan orogenic belt in Kyrgyzstan consists predominantly of Neoproterozoic to early Paleozoic assemblages and tectonically interlayered older Precambrian crystalline complexes and formed during early Paleozoic accretionary and collisional events. One of the oldest continental fragments of late Mesoproterozoic (Grenvillian) age occurs within the southern part of the Kyrgyz North Tianshan. Using SHRIMP zircon ages, we document two magmatic events at ~ 1.1 and ~ 1.3 Ga. The younger event is characterized by voluminous granitoid magmatism between 1150 and 1050 Ma and is associated with deformation and metamorphism. The older event is documented by ~ 1.3 Ga felsic volcanism of uncertain tectonic significance and may reflect a rifting episode. Geochemical signatures as well as Nd and Hf isotopes of the Mesoproterozoic granitoids indicate melting of still older continental crust with model ages of ca 1.2 to 2.4 Ga.The Mesoproterozoic assemblages are intruded by Paleozoic diorites and granitoids, and Nd and Hf isotopic systematics suggest that the diorites are derived from melts that are mixtures of the above Mesoproterozoic basement and mantle-derived material; their source is thus distinct from that of the Mesoproterozoic rocks. Emplacement of these plutons into the Precambrian rocks occurred between 461 and 441 Ma. This is much younger than previously assumed and indicates that small plutons and large batholiths in North Tianshan were emplaced virtually synchronously in the late Ordovician to early Silurian.The Mesoproterozoic rocks in the North Tianshan may be remnants of a once larger continental domain, whose fragments are preserved in adjacent blocks of the Central Asian Orogenic Belt. Comparison with broadly coeval terranes in the Kokchetav area of northern Kazakhstan, the Chinese Central Tianshan and the Tarim craton point to some similarities and suggests that these may represent fragments of a single Mesoproterozoic continent characterized by a major orogenic event at ~ 1.1 Ga, known as the Tarimian orogeny.  相似文献   

Lithosphere of the Dharwar craton by joint inversion of P and S receiver functions   总被引：1，自引：0，他引：1  

S. Kiselev  L. Vinnik  S. Oreshin  S. Gupta  S. S. Rai  A. Singh  M. R. Kumar  G. Mohan 《Geophysical Journal International》2008,173(3):1106-1118

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Spectrum of hot water in the 4750–13 000 cm⁻¹ wavenumber range (0.769–2.1 μm)     

Nikolai F. Zobov  Sergei V. Shirin  Roman I. Ovsyannikov  Oleg L. Polyansky  Robert J. Barber  Jonathan Tennyson  Peter F. Bernath  Michel Carleer  Reginald Colin  Pierre-François Coheur 《Monthly notices of the Royal Astronomical Society》2008,387(3):1093-1098

The high resolution laboratory spectrum of hot water vapour has been recorded in the 500–13 000 cm⁻¹ wavenumber range and we report on the analysis of the 4750–13 000 cm⁻¹ (0.769–2.1 μm) portion. The emission spectrum was recorded using an oxy-acetylene welding torch and a Fourier transform spectrometer. Line assignments in the laboratory spectrum as well as in an absorption spectrum of a sunspot umbra were made with the help of the BT2 line-list. Our torch spectrum is the first laboratory observation of the 9300 Å'steam bands' seen in M-stars and brown dwarfs.  相似文献   

Ammonites and stratigraphy of the terminal part of the Middle Volgian Substage (Upper Jurassic; Epivirgatites nikitini zone and its equivalents) of the Panboreal Realm: 1. Late morphogenesis and systematics of Dorsoplanitinae     

D. N. Kiselev 《Stratigraphy and Geological Correlation》2017,25(2):188-228

Problems of correlation of the upper part of the middle Volgian beds of European Russia and Arctic regions with the Portlandian of England and northern France largely result from existing uncertainties in the taxonomy of the ammonite subfamily Dorsoplanitinae. The poor knowledge of the morphogenesis of this group precludes effective and stable taxonomy and recognition of parallelisms, thereby decreasing the group’s correlative-biostratigraphic potential. In Dorsoplanitinae, dimorphism is revealed in the differences in the terminal shell diameter and, to a lesser extent, in the sculpture, whereas apertural modifications characteristic of many Perisphinctoidea are not observed in members of this group. The middle Volgian Dorsoplanitinae are represented by minimorphs and macromorphs, taxonomically different at the species or genus level. The Volgian minimorphs are mainly represented by the genera Epivirgatites and Lomonossovella, whereas macromorphs are represented by Titanites s.l.; in the genus Taimyrosphinctes, micro- and macromorphs belong to different subgenera. All morphological types of Volgian Dorsoplanitinae have vicariate equivalents in the Portlandian, which can be used for the interregional correlations.  相似文献   

Potassium basalts and picrobasalts from the devonian kimberlite fields of Western Yakutia, Russia, and their relations to kimberlite magmatism     

A. I. Kiselev  V. V. Yarmolyuk  K. N. Egorov 《Geology of Ore Deposits》2009,51(1):33-50

Basic explosion pipes occur along with basic dikes, sills, and chonoliths within the Vilyui—Markha basic dike belt in the northwestern marginal part of the Vilyui Rift, characterized by widespread basaltic magmatism. The explosion pipes are of interest for exploration geology owing to their specific composition and tectonic setting, similar in many respects to the structural localization of kimberlite bodies in the sedimentary cover of the Siberian Platform. The basic explosion pipes from the Mirny district were referred to as tholeiitic and alkali-basaltic petrochemical rock series. Peculiar potassic and ultrapotassic rocks—potassium olivine basalts and picrobasalts—were identified in the alkali-basaltic series. These rocks were regarded as related to the deepest sources among basalts and were recommended for use as a prospecting guide for primary diamond sources. Our investigations allowed us to interpret the elevated K and Mg contents in basic fragments from some explosion pipes and associated intrusive bodies as a result of low-temperature metasomatic alteration. The explosion breccias and metasomatically altered basic rocks probably mark areas favorable for explosion activity and intrusion of both basic and kimberlitic rocks.  相似文献   

The astrometric observations of planetary satellites, close approaches and occultations of stars by asteroids and mutual events in the systems of planetary satellites with the 26-in. refractor of Pulkovo observatory in 1995-2006     

T.P. Kiseleva  I.S. Izmailov  A.A. Kiselev  E.V. Khrutskaya  M.Yu. Khovritchev 《Planetary and Space Science》2008,56(14):1908-1912

Astrometric and photometric observations of major planets, their satellites and asteroids have been made with the 26-in. refractor of the Pulkovo observatory during the period from 1995 to 2006. The CCD (ST6) and photographic observations were carried out. Accurate relative position of satellites of Jupiter and Saturn have been derived. The positions of Saturn have been calculated using the theoretically predicted coordinates of satellites relative to the planet without measurements of the photographic images of the planet. Also the observations of Hale-Bopp comet and Mercury transit have been made. The 26-in. refractor has been included into the international campaign PHEMU-2003: photometric CCD observations of mutual occultations and eclipses of Galilean satellites. The light curves of the events have been obtained and parameters of the events have been determined.  相似文献