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1.
G. T. Skublov Yu. B. Marin S. G. Skublov Yu. N. Tarasenko 《Geology of Ore Deposits》2008,50(7):535-550
Volkhovites—tektite-like glasses—have been detected in the Holocene glacial drift along the right bank of the Volkhov River. A cryptomagmatic model of their formation and pre-Holocene age of volkhovite melts, cinder, and frothed glasses has been suggested (Skublov et al., 2007). Four geochemical types of volkhovites are distinguished: (1) manganous (Mn, Fe, Cr, V, Si, Nb, Pb, H), (2) magnesian (Mg, Al, Ti, F, B), (3) potassic (K, Rb, Cs), and (4) calcic (Ca, REEs, Ba, U, Th, Ta, Hf, Y, Sc, Cl). In light of the geochemical data, volkhovites are regarded as natural silicate glasses of kimberlite-carbonatite composition. Their types are called kimberlitic (Mn type), kimberlitic-carbonatitic (Mg type), lamproitic-carbonatitic (K type), and carbonatitic (Ca type). Volkhovites are suggested to be indicators of undiscovered diamond mineralization of kimberlite or carbonatite (Chagatai) types. 相似文献
2.
Doklady Earth Sciences - The fossil remains of a seal of the genus Pachyphoca from the Upper Miocene Sarmatian stratum of the Morskaya-3 site (Neklinovskii district, Rostov region) were described.... 相似文献
3.
Doklady Earth Sciences - A new species, Pachyphoca volkodavi, has been described based on seal remains from the Upper Miocene deposits of the Fortep’yanka locality in the Republic of Adygea.... 相似文献
4.
N.A. Tchepkaia G.A. Chelnokov A.A. Karabtsov I.A. Tarasenko 《Journal of Geochemical Exploration》2006,88(1-3):148
This study presents new data on major, trace and REE element concentration of groundwaters in Lastochka spa located in the northern part of Primorye, Far East of Russia. The studied area is characterized by two types of groundwaters issued from a spring and wells: fresh waters with low mineralization (Total Dissolved Solids is up to 400 mg/l) and high pCO2 waters with high mineralization (TDS is up to 4700 mg/l). New data and previous δ13C(TIC), oxygen (δ18O) and hydrogen (δ2H) isotope data indicate that these waters result from meteoric water infiltration in the Sikhote–Alin mountain, circulating at shallow depths in sedimentary rocks. CO2 in groundwater is of mantle origin. 相似文献
5.
In the footsteps of Alexander the Great: searching for the origins of ancient zooplankton on the wild steppe of Central Asia 
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下载免费PDF全文 Mark Williams David J. Siveter Vincent Perrier Elena Mikhailova Anna Tarasenko Firuza Salimova Irina A. Kim 《Geology Today》2015,31(2):68-73
Rising above the modern town of Nurata, in Navoiy Province, eastern Uzbekistan is the ancient fortress of Alexander the Great, built as part of Alexander's campaigns to subjugate the Persian‐speaking Sogdian peoples that lived in this province of the Persian Empire in the 4th Century bc . Alexander passed this way in 327 bc , marching his ancient army through this beautiful but desolate landscape, and conquering all before him. His fortress was built in a strategic place at the boundary between fertile agricultural lands and a dry and uncompromising vastness of steppe that lies to the east. From Nurata, about one hour drive by car along a road that cuts eastwards across the desert, is the sleepy town of Jo'sh. In the mountains beyond Jo'sh sits the hamlet of Kanda, a few mud‐brick houses nestling at the head of a small valley where a spring emerges miraculously from a bone‐dry landscape. Hereabouts are telltale signs of ancient marine deposits yielding graptolites from rocks of the Silurian system. And in these rocks are the fossils of tiny arthropods that mark a fundamental shift in the marine arthropod zooplankton 425 million years ago. It is these fossils that we have chased halfway across the world to the steppe of Central Asia. 相似文献
6.
Space monitoring of Aral Sea degradation 总被引：1，自引：0，他引：1
The results of remote sensing survey of the Aral Sea in its degradation period are given. Satellite images are used to map
shoreline retreat from 1961 to 2008 and to measure the decrease in the area. Seasonal variations in shoreline and water area
are identified, suggesting seasonal level variations and correlating well with data of satellite altimetry surveys of sea
level. Observations covered surge phenomena, seasonal dynamics of landscapes, and the seasonal salinization rhythm in coastal
territories with the subsequent formation and weathering of salt crusts. The character of river runoff input into the Great
Sea resulting from overbank flooding in artificial water bodies in the Amu Darya delta is identified. 相似文献
7.
G. T. Skublov Yu. B. Marin S. G. Skublov E. V. Vasil’ev I. M. Gembitskaya E. S. Nechaeva Yu. N. Tarasenko 《Geology of Ore Deposits》2009,51(8):698-711
Kirishites are highly carbonaceous hairlike fibers 30–100 μm in thickness and 3–30 mm long, which jut out as bunches on the
surface of cinder and shungite fragments associated with volkhovites (Holocene tectitelike glasses corresponding to the rocks
of kimberlite-lamproite-carbonatite series in composition). Kirishite fibers are zonal. Their inner (axial) zone is composed
of high-nitrogen proteinlike compounds, whereas the outer zone is essentially carbonaceous, with a high content of organoelemental
complexes (Si, Fe) and numerous micrometer-sized anomalies of major, volatile, trace, and ore elements. Longitudinal zoning
is established in aposhungite kirishites: the consecutive change of maximum concentrations—K, Na, Cl, C, Mn → C, S, V, Ni,
Cu, Zn → S, N, Ba, Te, Pb, Bi, Nd—is traced from the roots of fibers to their ends. It is suggested that as volkhovites were
forming, fragments of cinder and shungite underwent partial melting. The highly carbonaceous compounds released due decompression
and explosion were squeezed out from fragments and solidified as fibers during fall of fragments on the Earth’s surface. 相似文献
8.
G. T. Skublov Yu. B. Marin V. M. Semikolennykh S. G. Skublov Yu. N. Tarasenko 《Geology of Ore Deposits》2007,49(8):681-696
Volkhovites are tektite-like glasses of mafic and ultramafic composition discovered in the fluvioglacial drift of the Valdai glaciation (10–60 ka ago) along the right bank of the Volkhov River (59°27′ N, 32°01′ E). Volkhovite particles are small in size (0.1–3.0 mm) and irregular in shape, with various microtektite aerodynamics (globular, droplike, and dumbbell-like forms). They are perfectly preserved, and, thus, postglacial in age. Sporadic volkhovite grains (up to 20 items per 1 kg of loam) were detected over an area 1.0 × 1.5 km2. Some samples from local spots 20 × 30 m2 in size are anomalously enriched, up to 1700 volkhovite grains per 1 kg of loam. Tiny Ti-Fe, Fe, and Cu-Au spherules, particles of quenched glass and cinder, and fragments of the Precambrian and Paleozoic rocks are spatially associated with volkhovites. The suggested cryptomagmatic model assumes that the glass and cinder are pre-Holocene in age, whereas volkhovites were formed in the post-glacial time as a result of the outburst of the slag-stone-melt-mud-gas mixture that ascended from the asthenosphere to the surface. Drops of the melt solidified in the air instantaneously to form tectite-like glasses, and the tuffisite-like agglomerate mixed with the fluvioglacial drift. 相似文献
9.
Volkova N. E. Ivanyutin N. M. Tarasenko V. S. Pashtetskii V. S. Podovalova S. V. 《Water Resources》2022,49(4):533-542
Water Resources - The aggravating deficiency of water resources in the Republic of Crimea emphasizes the necessity of their rational use. As this should be based on the rational water policy, this... 相似文献
10.
T. V. Tarasenko 《Water Resources》2013,40(2):111-119
At present, close attention is given to studies of thermokarst lakes from the standpoint of cryolite zone response to global climate warming. However, other factors, which have an effect on the variation in areas of lakes, in particular, the atmospheric precipitation, receive little attention, while the atmospheric precipitation is one of the main sources of water recharge for many water objects. In this connection, interannual variations in the areas of lakes as a function of precipitation were analyzed on the territory of Central Yakutia. The studies were based on the analysis of space images taken at different time. As the result, it was shown that precipitation has a considerable effect on variations in the areas of thermokarst lakes; there is a direct relationship between variations in lake areas and precipitation; only some single high-water or low-water years have no effect on these variations. Variations in areas of lakes during summer were also analyzed with a view to use the results in choosing the images for studies of interannual variations. It has been revealed that the areas of thermokarst lakes decrease from June to August; this means that the images obtained within a short period at the end of the summer period should be used. 相似文献