The tectonic structure of the junction zone between Lomonosov Ridge and the Arctic Continental Margin of Eurasia was clarified due to comprehensive analysis of data on the potential fields and the ...results of the newest seismic surveys. The existence of the hypothetical Khatanga–Lomonosov transform zone is not confirmed by the established system of disjunctive dislocations. The results obtained confirmed and detailed the model, according to which the opening of the Eurasian Basin was accompanied by movement of the Lomonosov Ridge and adjacent from the east and south geological structures, as a parts of the North American Plate, away from the Barents–Kara margin.
The history of the 2.5 million km2 Amerasia Basin (sensu lato) is in many ways the least known in the global tectonic system. Radically different hypotheses proposed to explain its origin are ...supported only by inconclusive and/or indirect observations and several outstanding issues on the origin of the Basin remain unaddressed. The difficulty lies in the geodynamic evolution and signature of the Basin being overprinted by excess volcanism of the Alpha–Mendeleev Ridge complex, part of the High Arctic Large Igneous Province (HALIP) and one of the largest (>1 million km2) and most intense magmatic and magnetic complexes on Earth. Here, we present the results of a 550,000km2 aerogeophysical survey over the poorly explored Lomonosov Ridge (near Greenland) and adjoining Amerasia and Eurasia Basins that provides the first direct evidence for consistent linear magnetic features between the Alpha and Lomonosov Ridges, enabling the tectonic origin of both the Amerasia Basin and the HALIP to be constrained. A landward Lower Cretaceous (∼138–125(120)Ma) giant dyke swarm (minimum 350×800km2) and tentative oceanward Barremian (or alternatively lower Valanginian–Barremian) seafloor spreading anomalies are revealed. Prior to Cenozoic opening of the Eurasia Basin the giant dyke swarm stretched from Franz Josef Land to the southern Alpha Ridge and possibly further to Queen Elisabeth Islands, Canada. The swarm points towards a 250-km-wide donut-shaped anomaly on the southern Alpha Ridge, which we propose was the centre of the HALIP mantle plume, suggesting that pronounced intrusive activity, associated with an Alpha Ridge mantle plume, took place well before the Late Cretaceous Superchron and caused continental breakup in the northern Amerasia Basin. Our results imply that at least the southern Alpha Ridge as well as large parts of the area between the Lomonosov and southern Alpha Ridges are highly attenuated continental crust formed by poly-phase breakup with LIP volcanic addition. Significantly, our results are consistent with an early (∼pre-120Ma) overall continental scale rotational opening of the Amerasia Basin in which the Eurasian continental margin is rifted from the Canadian–southern Alpha Ridge margin about one or more poles in the Mackenzie Delta (Alaska). The findings provide a key to resolving Arctic plate reconstructions and LIPs in the Mesozoic.
► We present the results of a regional aeromagnetic survey in the Arctic Ocean. ► We demonstrate a Lower Cretaceous giant dyke swarm (350×800km) and Barremian MORB. ► The dyke swarm is linked to initial main HALIP activity on the Alpha Ridge. ► Our results support an early rotational opening model of the Amerasia Basin. ► We question the general oceanic crustal views of the Alpha and Mendeleev Ridges.
A seismic stratigraphic framework and basin fill geohistory for Arctic Ocean basins is presented based on data collected by several Russian Government organized expeditions to the Arctic Ocean. This ...analysis tied together seismic stratigraphic interpretations for the shelf and the deep-water part of the ocean. The stratigraphic framework is based on age data derived from linear magnetic anomalies in the Eurasia Basin, borehole data for the Lomonosov Ridge and Alaska Shelf, and correlations with various regional geological events. Six seismic boundaries were identified and traced regionally over large areas. We present as a hypothesis that the Arctic Ocean probably was formed during four phases with different kinematics: 133-125 Ma – Canada Basin opening, 125-80 Ma – superplume-related tectonics and magmatism in the Alpha-Mendeleev Rise area and adjacent basins, 80-56 Ma - strike-slip fault tectonics, and 56-0 Ma – Eurasia Basin opening. The time interval of 45-20 Ma appears to be a period of large-scale vertical intraplate movements and normal faulting. Climatic events are recorded in the sedimentary cover of the Arctic Ocean.
The analyses were based on a comprehensive dataset that included more than 23,000 km of 2D seismic lines, which were acquired in the deep-water part of the ocean, supplemented by a large number of federal and commercial seismic lines, which were acquired for the Russian shelves during the past 10-15 years. In addition, special multiple Russian expeditions collected samples on scarps of the Mendeleev Rise that served as ground truth for the seismic interpretation.
•New seismic stratigraphy of the Arctic Ocean region.•Great Aptian to Albian continental rift and magmatic epoch.•SDRs and volcanoes in the Mendeleev Rise region.
Over a period of the past 15–20 years, the Russian Government implemented the Arctic Mega Project for geological and comprehensive study of the Arctic Ocean. In this paper we discuss the methods that ...were used in the implementation of this project. In the course of several expeditions, multiple types of data were acquired, which included: (1) seismic data of different types, (2) subbottom profiler data, (3) geological sampling on slopes of the Mendeleev Rise with the use of special equipment, (4) borehole drilling, (5) gravity and magnetic anomalies, (6) offshore geodetic data, (7) multi-beam bathymetry surveys, and (8) field surveys on multiple Arctic islands. Several nuclear icebreakers and a scientific research submarine were deployed in these operations. Specifically, more than 23,000 km of 2D multi-channel seismic lines and more than 4000 km of wide-angle refraction/reflection seismic lines were acquired, in addition to subbottom profiles for the Eurasia Basin and new bathymetric data of the Arctic Ocean. The new database is intended to facilitate the development of new insights into Arctic geology and geodynamics and contribute to a better understanding of the structure and tectonic evolution of the Arctic Ocean as a whole.
•Arctic Ocean mega project in geosciences.•Geological sampling on slopes of the Mendeleev Rise.•New and improved geophysical data.
В порядке следования слов в русском литературном языке XVIII века, по замечанию многих иссле-дователей, еще не было строго закрепившейся нормы, однако грамматисты XVIII–XIX веков пред-принимали в ...своих учениях попытки объяснить расположение тех или иных частей речи. Особую роль в закреплении норм словорасположения сыграло учение М. В. Ломоносова, изложенное в его риторических трактатах.
В данной статье описывается функционирование атрибутивных словосочетаний в похвальных словах Ф. Прокоповича, М. В. Ломоносова и А. П. Сумарокова середины XVIII века. Целью настоя-щей работы является анализ порядка компонентов в атрибутивных словосочетаниях в похвальных словах XVIII века, а также описание стилистических средств, использующихся в словорасположе-нии данных атрибутивных конструкций.
Используя метод сплошной выборки, авторы выявили в привлеченных к анализу текстах 1837 атрибутивных конструкций. Преобладающим положением как в двучленных, так и в трехчленных словосочетаниях является препозиция атрибута. Однако было замечено, что количество препози-тивных атрибутивных словосочетаний в панегириках отличается: так, в текстах Ф. Прокоповича препозитивный атрибут используется в половине случаев, тогда как в текстах М. В. Ломоносова и А. П. Сумарокова препозиция атрибута увеличивается, доходя до 82%.
В панегириках М. В. Ломоносова, Ф. Прокоповича и А. П. Сумарокова атрибуты широко упо-требляются в роли однородных членов, наблюдается лексический и синтаксический повтор, спо-собствующий амплификации, и чередование препозитивного и постпозитивного атрибута; ис-пользуются конструкции с дистантным положением членов атрибутивного ряда, посредством параллельного расположения атрибутов подчеркивается противопоставление выражаемых при-знаков или объектов.
В похвальных словах важное место занимают атрибутивные словосочетания, активно используе-мые как стилистическое средство. Так, ряды определений содействуют созданию портрета истори-ческого лица (в данном материале – Петра Великого), которому посвящен панегирик, а также ярко-му изображению его деяний, военных подвигов. Ряды эпитетов, адъективных метафор, сравнение, градация, хиазм, инверсия, другие тропы и фигуры речи – важный в исследовательском плане мате-риал, демонстрирующий корреляцию между представленными в трактатах по теории красноречия и риторической практикой эпохи становления новых норм русского литературного языка после-петровского периода. Атрибутивные конструкции в похвальных словах XVIII века являются сти-листическим средством усиления экспрессивности выражения и создания торжественного пафоса.
We explore the use of Mg/Ca ratios in six Arctic Ocean benthic foraminifera species as bottom water palaeothermometers and expand published Mg/Ca-temperature calibrations to the coldest bottom ...temperatures (<1 °C). Foraminifera were analyzed in surface sediments at 27 sites in the Chukchi Sea, East Siberian Sea, Laptev Sea, Lomonosov Ridge and Petermann Fjord. The sites span water depths of 52–1157 m and bottom water temperatures (BWT) of −1.8 to +0.9 °C. Benthic foraminifera were alive at time of collection, determined from Rose Bengal (RB) staining. Three infaunal and three epifaunal species were abundant enough for Mg/Ca analysis. As predicted by theory and empirical evidence, cold water Arctic Ocean benthic species produce low Mg/Ca ratios, the exception being the porcelaneous species Quinqueloculina arctica. Our new data provide important constraints at the cold end (<1 °C) when added to existing global datasets. The refined calibrations based on the new and published global data appear best supported for the infaunal species Nonionella labradorica (Mg/Ca = 1.325 ± 0.01 × e^(0.065 ± 0.01 × BWT), r2 = 0.9), Cassidulina neoteretis (Mg/Ca = 1.009 ± 0.02 × e^(0.042 ± 0.01 × BWT), r2 = 0.6) and Elphidium clavatum (Mg/Ca = 0.816 ± 0.06 + 0.125 ± 0.05 × BWT, r2 = 0.4). The latter is based on the new Arctic data only. This suggests that Arctic Ocean infaunal taxa are suitable for capturing at least relative and probably semi-quantitative past changes in BWT. Arctic Oridorsalis tener Mg/Ca data are combined with existing O. umbonatus Mg/Ca data from well saturated core-tops from other regions to produce a temperature calibration with minimal influence of bottom water carbonate saturation state (Mg/Ca = 1.317 ± 0.03 × e^(0.102 ± 0.01 BWT), r2 = 0.7). The same approach for Cibicidoides wuellerstorfi yields Mg/Ca = 1.043 ± 0.03 × e^(0.118 ± 0.1 BWT), r2 = 0.4. Mg/Ca ratios of the porcelaneous epifaunal species Q. arctica show a clear positive relationship between Mg/Ca and ΔCO32− indicating that this species is not suitable for Mg/Ca-palaeothermometry at low temperatures, but may be useful in reconstructing carbonate system parameters through time.
Vectors of culture Elina, Elena G.
Izvestiâ Saratovskogo universiteta. Novaâ seriâ. Seriâ Filologiâ. Žurnalistika (Online),
11/2022, Letnik:
22, Številka:
4
Journal Article
Recenzirano
Odprti dostop
This is a review of a collected volume of articles prepared by Professor M. Stroganov for his 70th Anniversary. The book intertwines two main academic interests of the author, mixed up in a special, ...unique to the researcher, methodological paradigm. These are the attention to the literary or folklore text as well as the focus on the diversity of Russian culture in its broadest spectrum: song and singing, music and painting, and the various facets of the theatrical arts. These two components of academic exploration in the work of Stroganov are in constant interaction and mutual influence. The author goes on to explore not only the obvious manifestations of these connections, but also sees in them the d riving force of all Russian artistic thought, the search for the aesthetic ideal, and the answers to the burning questions of Russian life. The key aspect explored in the book’s chapters is the dialectics of high culture and mass culture. The author argues that mass culture is not just a negative episode in the development of a culture which should be resolved to avoid distortions, but a feature of the historical development of society. This occurs, according to the author, due to the fact that mass culture is formed simultaneously with the emergence of the original high literature. The opinions of many prominent literary and artistic figures against the cheap popularity of mass culture, its gravitation towards tastelessness, violation of sacredness, trivialisation and distortion of the sublime, provoke the author of the reviewed book to have a serious and substantiated discussion about the mass culture. For the author, mass culture has its own parameters and boundaries, with its own separate tasks and ways of realisation; it has its own reader-viewer-listener, and is thus the most important object of an academic study. М. Stroganov formulates the specifics of this object and creates a system for its analytical description.
This paper broadens the description of sedimentary organic matter from the conventional use of coal petrography to include palynological and geochemical sedimentary organic matter. Palynological ...sedimentary organic matter includes all chemically resistant organic microfossils, such as pollen and spores, dinocysts, microforaminifera (chitinoid-like linings of foraminifera), microscopic algae, charcoal, palynodebris, acritarchs, chitinozoans, and scolecodonts. Geochemical sedimentary organic matter includes organic biomarkers, lipids, and photosynthetic pigments. We provide examples of the use of palynological and geochemical analysis of sedimentary organic matter to understand patterns and impacts of changing climate, fire regimes, hydrologic extremes, water quality, and land change on terrestrial and marine systems through geologic time to provide a long-term perspective to evaluate anthropogenic impacts on the Earth as well as to support forensics investigations.
The Palaeocene/Eocene thermal maximum, ∼55 million years ago, was a brief period of widespread, extreme climatic warming, that was associated with massive atmospheric greenhouse gas input. Although ...aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition. We show that sea surface temperatures near the North Pole increased from ∼18 °C to over 23 °C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations, but the absolute polar temperatures that we derive before, during and after the event are more than 10 °C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms—perhaps polar stratospheric clouds or hurricane-induced ocean mixing—to amplify early Palaeogene polar temperatures.
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