Науки о земле

В учебном пособии изложены основные факты и сведения о географическом положении, населении, политике, образовании, культуре, национальном характере англоязычных стран – Великобритании и США. Пособие содержит лекционный материал, тексты для дополнительного чтения, творческие задания, вопросы для самопроверки, а также упражнения для расширения лексического запаса студентов в целях формирования и развития у студентов общепрофессиональных компетенций. Пособие предназначено для обучающихся по направлениям подготовки 44.03.05 Педагогическое образование, 45.03.02 Лингвистика.

The question of digital core modelling appears highly relevant due to the fact that there is not always a sufficient amount of core material available from studied wells: in some cases, it is not possible to select core material (in case of loose, weakly cemented rocks); in others, such material may be completely absent. In order to create a computer model of a digital core, it is necessary to have a correct understanding of the pore space microstructure and rock lithological composition and structure, among the most important features determining the quality of sedimentary reservoir rocks. Such information can be obtained by carrying out lithological-petrographic studies of thin sections of reference (standard) core samples. The aim of the present work is to study petrographic thin sections for their further use in creating a digital core model. The article discusses the methodology and results of laboratory lithological and petrographic studies of thin sections using the available core information. The paper presents the results of laboratory studies of thin sections of terrigenous sandstones obtained from the Berea Sandstone formation (USA). The choice of the Berea Sandstone is due to its wide recognition by specialists, as well as its homogeneity, both in terms of the grain size of constituent rocks and their filtration and reservoir properties. The work also presents the results of data analysis on lithological and petrographic studies of core material from the terrigenous deposits obtained in the Timan-Pechora province in northern Russia. The research results can be used for mathematical modelling of the pore space microstructure in a digital core model.

Many Russian gas fields in the Arctic are now in the final development stage, so there is a need for additional gas compression along the gas collection system between the wells and the gas processing plant. After the compression stage, the gas is cooled in air cooling units (ACU). Cooling crude (wet) gas in low-temperature environments using ACUs involves a risk of hydrate plugs forming in the ACU’s heat transfer tubes. Variable frequency control of speed fans is typically used to control performance of the ACUs and the control criterion is the gas temperature at the ACU outlet. Even so, the chances of hydrate forming in the bottom of the tube bundle remain large owing to inhomogeneous distribution of the gas temperature in the tube bundles and the temperature jump between the inner surface of the tube wall and the gas flowing through that tube, despite the high gas temperature in the outlet header. To enable forecasting of possible hydrate formation, the mathematical model of the ACU’s thermal behaviour that forms the basis of control system’s operating procedure must ensure proper calculation not only of the gas temperature at ACU outlet but also the dew point at which condensate formation begins and the hydrate formation temperature. This article suggests a simulation model for crude gas ACU thermal behaviour that enables modelling of both the temperature pattern of the gas inside the tube and the areas of condensate and hydrate formation. The described thermal behaviour model may be used in ACU management systems.

The radiological state of the land and water areas constantly attracts public interest. Specially protected natural reservations deserve special attention when it comes to studying radiological conditions. This study presents findings of radioecological investigations conducted in the Kostomuksha State Nature Reserve in 2012 – 2015. The Kostomuksha Mining Company, which is developing the Kostomuksha iron ore deposit was identified as a potentially hazardous facility that might affect the radioecological situation in the naturel reserve, since production of iron ores at the deposit involves extraction to the ground surface of acid rocks characterised by a naturally high content of radioactive elements (granitic gneiss). Furthermore, several sources of radioactive radon gas have been identified within the reserve boundaries. The study included investigation of natural and anthropogenic radioactivity in the environmental components of the nature reserve and adjacent territories, including soil, plants, bottom sediments, ambient air and natural waters. It was found that development of the Kostomuksha iron ore deposit and operations of the mining and processing plant do not exert any considerable impact on the radiological situation in the nature reserve. Data obtained during the study indicate that the overall radiological situation in the reserve is acceptable and meets the relevant radiation safety standards. High levels of radiocesium were found in the moss and bottom sediments of the nature reserve, which requires additional research to determine a wider pattern of distribution of anthropogenic radioactivity across the adjacent territories and to study the processes of buildup and migration of radionuclides in aquatic organisms of Kamennoye Lake.

Журнал публикует оригинальные исследовательские статьи, обзоры и краткие сообщения по исследованиям в Арктике и прилегающим к ней районам. Преимущество отдается рукописям, основанным на проведенных полевых и лабораторных исследованиях и экспериментах, а также посвященным математическому моделированию процессов, протекающих в высоких широтах. The journal publishes original research articles, reviews and notes on research in the Arctic and adjacent areas. Preference is given to manuscripts based on field and laboratory research and experiments, as well as on mathematical modelling of processes taking place in high latitudes. The journal presents the results of research within: geosciences (geology, geodesy and cartography, geoinformatics, geoecology, engineering geology, geocryology and pedology, prospecting and exploration of hard minerals, oil and gas fields) and biological sciences (biogeography, botany, microbiology, zoology, genetics, ecology, hydrobiology, parasitology, mycology, soil science, and biological resources).