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1.
Simanovich I. M. Golovin D. I. Bujakaite M. I. Vinogradov V. I. Sakharov B. A. Matsapulin V. U. Sokolova A. L. Pokrovskaya E. V. 《Lithology and Mineral Resources》2004,39(6):555-565
The influence of geodynamic factors on the postsedimentary lithogenesis of terrigenous sequences during the replacement of the passive continental-margin regime to the active regime is considered with the Toarcian–Aalenian complexes of southern Dagestan as an example. It has been established that clayey rocks were lithified under conditions of subsidence lithogenesis, whereas the orogenic catagenesis of sandy rocks was related to stress initiated by the initial (amagmatic) subduction phase. The Kübler index has been used to reveal the postsedimentary zonality that is consistent with the intensity of folding and cleavage. The metagenesis zone fits the cleavage zone. The Rb–Sr and K–Ar datings of clayey rocks from the metagenesis zone yielded 180–190 Ma that can be interpreted as the timing of the maximal manifestation of postsedimentary lithogenesis. 相似文献
2.
O. V. Ilyina N. S. Tychkov A. M. Agashev A. V. Golovin A. E. Izokh O. A. Kozmenko N. P. Pokhilenko 《Doklady Earth Sciences》2016,467(2):408-411
The results of the first study of the PGE distribution in deformed lherzolites of the Udachnaya kimberlite pipe (Yakutia) are presented here. The complex character of evolution of the PGE composition in the Deformed lherzolites is assumed to be the result of silicate metasomatism. At the first stage, growth in the amount of clinopyroxene and garnet in the rock is accompanied by a decrease in the concentration of the compatible PGE (Os, Ir). During the final stage, the rock is enriched with incompatible PGE (Pt, Pd) and Re possible due to precipitation of submicron-sized particles of sulfides in the interstitial space of these mantle rocks. 相似文献
3.
I. S. Sharygin A. V. Golovin A. V. Korsakov N. P. Pokhilenko 《Doklady Earth Sciences》2016,467(1):270-274
Tychite Na6Mg2(CO3)4(SO3) is a rare natural Na and Mg sulfatocarbonate. It is found only as minor mineral in deposits of saline lakes in the United States, Canada, Uganda, and China. In these continental evaporites tychite has sedimentary genesis. In this study, we report the first occurrence of tychite as a crystal phase in the melt inclusions in olivine from mantle xenoliths of the Udachnaya-East kimberlite pipe. This find provides an evidence for the probability of tychite crystallization from melts; i.e., this rare sulfatocarbonate may have a magmatic origin as well. 相似文献
4.
Yu. V. Kushcheva I. V. Latysheva D. I. Golovin Yu. O. Gavrilov 《Lithology and Mineral Resources》2007,42(3):257-267
Results of the comprehensive study of structural, lithological, mineralogical, and isotopic characteristics of Lower Jurassic rocks exposed in the Belaya River valley (Adygeya) in meganticlinorium of the Greater Caucasus are presented. Deformation microstructures were studied. Lithological and textural-structural changes in sequences related to intense secondary transformations should affect the state of isotopic systems of rocks. To reveal basic trends in the evolution of isotopic systems, investigation using the K-Ar method was carried out. Clay fraction (less than 1 μm) separated from rocks and bulk samples were analyzed. Cleavage development, approximate value of rock contraction, and isotopic characteristics are compared with the available data on alteration of clay mineral assemblages. Relationship between the degree of rock deformation at the microlevel and calculated K-Ar ages has been established. K-Ar systems of clayey rocks indicate the age of cleavage formation and correspond to the Bajocian-Bathonian contraction period. 相似文献
5.
V. S. Sheimovich D. I. Golovin D. O. Gertsev 《Journal of Volcanology and Seismology》2007,1(4):248-253
The hornblende andesite extrusion of Mount Mishennaya belongs to the andesite subcomplex of the Avacha Neopleistocene-Holocene basalt-andesite volcanic complex. The Mishennaya dome belongs to the extrusive areal field found on the north bank of Avacha Creek. It is believed that the subcomplex took a long time to develop from the Early to Late Neopleistocene. Three K-Ar age determinations of the Mishennaya andesites have been made using a hornblende monofraction for one determination and the nonmagnetic fraction of the rocks for the other two. The resulting age values are 0.60, 0.57, and 0.59 Myr. These are consistent with previous paleomagnetic determinations and with results from fission track analysis (0.7 Myr). 相似文献
6.
S. A. Borysenko Yu. V. Sizonenko I. V. Luk’yanyk A. V. Ivanova A. D. Voitsekhovskaya T. P. Sergeeva A. V. Golovin 《Kinematics and Physics of Celestial Bodies》2011,27(2):92-97
Photometric measurements of photographic images of comet C/1987 P1 Bradfield have been carried out with a flat-bed scanner
equipped with a slide module. Lengthwise and transverse photometric profiles of the cometary plasma tail have been obtained.
Magnetic field induction and some other physical characteristics of the cometary plasma tail observed in November 1987 have
been estimated with the use of the diffusion model for a cometary tail by Shul’man and Nazarchuk (1968). It has been shown
that the scanned images of comets can be used for estimating the physical characteristics of cometary tails. 相似文献
7.
8.
V.G. Trifonov A.E. Dodonov E.V. Sharkov D.I. Golovin I.V. Chernyshev V.A. Lebedev T.P. Ivanova D.M. Bachmanov M. Rukieh O. Ammar H. Minini A.-M. Al Kafri O. Ali 《Journal of Volcanology and Geothermal Research》2011,199(3-4):177-192
New data on geology and 21 K–Ar dates of the Late Oligocene–Quaternary basalts in Syria, combined with analysis of the new and previous data are used to reconstruct the volcanic history and relations between it and tectonic events. Volcanism began at the end of Oligocene (26–24 Ma) and was concentrated in the Late Oligocene–Early Miocene along a N-trending band, which stretches from the Jebel Arab (Harrat Ash Shaam) up to Kurd Dagh and southern Turkey. Activity waned in the Middle Miocene (17–12 Ma), but was resumed in the same band in the Tortonian and increased in the Messinian and Early Pliocene (6.3–4 Ma), when volcanism spread to the Shin Plateau and its coastal extension. After a brief hiatus ~ 4–3.5 Ma, volcanism became still more intensive and spread from the N-trending band to the east into the northern margin of the Mesopotamian Foredeep and to the west into the Dead Sea Transform zone. Additional eruptions continued into the Holocene.Volcanism lasted > 25 million years in the Jebel Arab Highland and > 15 million years in the Aleppo Plateau. The long duration of volcanism in the same parts of the moving Arabian plate and absence of records of one-way migration of the activity mean that the magmatic sources moved together with the plate, i.e., they were situated within the lithosphere mantle. Coincidence of the tectonic and volcanic stages of the Arabian plate development proves that volcanic activity depended on the geodynamic situation, caused by the plate motion. Situated within the lithosphere, magmatic sources within this transverse band were possibly caused by thermal and deforming influences of the asthenospheric lateral flow, moved laterally from the Ethiopia–Afar deep superplume. 相似文献
9.
Golovin A. V. Solovev K. A. Sharygin I. S. Letnikov F. A. 《Doklady Earth Sciences》2022,507(2):1044-1049
Doklady Earth Sciences - This paper reports the first discovery of zoned aragonite, a high-pressure CaCO3 polymorph, in a mantle xenolith from kimberlite. Aragonite is the most common epigenetic... 相似文献
10.
V. I. Vinogradov M. I. Bujakaite D. I. Golovin Yu. V. Kushcheva Yu. A. Ivanov V. N. Teslenko O. I. Pashicheva 《Lithology and Mineral Resources》2009,44(2):174-182
Rb-Sr and K-Ar characteristics of Vendian and Upper Riphean sections in various structural units of the East European Platform are studied. It is shown that Neoproterozoic clayey rocks of the platform underwent postsedimentary transformations, primarily owing to processes of K accumulation (illitization). Their intensity decreases with depth and isotopic signatures of provenance rocks are partly retained in Riphean rocks. Stages of the most active transformations approximately 400 and 600 Ma ago are manifested in the Vendian clayey rocks. Events of approximately 1000 Ma ago are recorded in Riphean rocks of the East European Platform. The least altered rocks of the Pachelma aulacogen can retain ancient hydrocarbon pools. 相似文献