scholarly journals Water tracks in the lower Lena River basin

2020 ◽  
Vol 163 ◽  
pp. 04007
Author(s):  
Anna Tarbeeva ◽  
Lyudmila Lebedeva ◽  
Vladimir Efremov ◽  
Vladimir Shamov ◽  
Olga Makarieva
Keyword(s):  
Active Layer ◽  
Surface Flow ◽  
Water Levels ◽  
Storm Event ◽  
Lena River ◽  
The North ◽  
Geological Conditions ◽  
North Western ◽  
Cryogenic Processes ◽  
Permafrost Regions

In the permafrost regions, where water filtration zone is limited by the shallow active layer, the surface flow forms a network of hollows, called «water tracks», oriented along the slope gradient. Water tracks are clearly distinguished on satellite images, but poorly defined in the field. The pattern of the water tracks network depends on geomorphological position, permafrost and geological conditions and dominant cryogenic processes. Surface flow could occur in the water tracks during the snowmelt and heavy rains, when the soil is entirely frozen or fully saturated by water. In dry periods, the water tracks form retention zones due to low filtration rates and significant capacity of thawed soil beneath the troughs. Our study of water tracks in the north-western Yakutia showed the changes of their morphology from upstream towards downstream. The water levels in the water tracks have a pronounced diurnal course in reverse phase to the water temperature variation. They are related to diurnal ground thawing dynamics. Hydrology of water tracks depends on the peat thickness, active layer properties and lithology. Water tracks formed by rubble rocks respond to a storm event with rapidly increasing water level. The deeper thawing layer, the smoother water levels rise and decrease.

Bearing capacity of frozen soils for foundations of objects in the North of Western Siberia

2020 ◽  
Author(s):  
Fedor Iurov ◽  
Valery Grebenets
Keyword(s):  
Bearing Capacity ◽  
Active Layer ◽  
Western Siberia ◽  
Transport Infrastructure ◽  
Pile Foundations ◽  
The Arctic ◽  
Frozen Soils ◽  
The North ◽  
Geological Conditions ◽  
Cryogenic Processes

<p>Keywords: permafrost, forecast, bearing capacity, foundation</p><p>The North of Western Siberia is a very promising region for industrial development. It is rich in oil and gas deposits, large settlements are located here and there is an extensive system of transport infrastructure (gas and oil pipelines, roads and railways). The territory has very differentiated permafrost-geological conditions in various types of landscapes. The development of new production sites, the construction and operation of infrastructure objects often activates dangerous cryogenic processes.</p><p>Trends in increasing air temperatures result in increase in the active layer depth, which leads to the decrease in the freezing area of frozen foundations, as well as in increase of the soil temperature, which reduces the forces of freezing. The problem is enhanced by the anthropogenic impact, which intensifies the negative changes in permafrost.</p><p>Quantitative estimation of changes in the bearing capacity of frozen pile foundations in the North of Western Siberia was carried out up to 2050 for various types of soils (sand, clay soils, peat) with trends in increasing temperatures of frozen soils and trends in increasing thickness of the active layer taken into account. Detailed calculations were carried out for the route of the “Vankor-Purpe” oil pipeline.</p><p>The calculations showed that maintaining current rate of climate warming, by 2050, there will be significant deterioration of the engineering-geocryological situation. The largest negative changes will take place in the southern part of the permafrost zone of Western Siberia (in the Tazovsky, Novourengoysky and Nadymsky districts), where the decrease in bearing capacity will exceed 50%. In the more northern regions (on the territory of Yamal), the predicted changes in the bearing capacity of frozen pile foundations by 2050 will not be so critical (no more than 20%). However, an increase in the thickness of the active layer can cause activation of the thermokarst process due to closeness of the thick stratal ice to the surface, as well as other destructive cryogenic processes.</p><p>In the region of investigation, under the influence of rising soil temperatures and an increase in the depth of seasonal thawing, the most vulnerable to climatic changes are loamy soils, which, according to the calculations, are characterized by the maximum decrease in the bearing capacity of frozen piles (up to 10% over 10 years). Sandy soils are more stable, a decrease in bearing capacity occurs in such areas at a lower speed (up to 5–7% over 10 years). Areas with moss-peat layer at the surface are less susceptible to changes in bearing capacity, however, with industrial methods of foundation construction, the layer is destroyed in places where the piles are built.</p><p>This work was supported by the RFBR grant 18-05-60080 “Dangerous nival-glacial and cryogenic processes and their impact on infrastructure in the Arctic”.</p>

scholarly journals LOCALIZATION CONDITIONS AND THE GOLD CONTENT OF THE SCARNS OF ZYGYRKOL ORE ZONE (KABARDINOBALKARSKAYA REPUBLIC)

2017 ◽  
Author(s):  
С.Г. Парада ◽  
В.В. Столяров
Keyword(s):  
Reverse Fault ◽  
Optimum Level ◽  
Gold Content ◽  
Minimum Level ◽  
Lower Section ◽  
The North ◽  
Geological Conditions ◽  
Localization Conditions ◽  
North Western ◽  
Gold Bearing

Охарактеризованы геологические условия локализации золотоносных скарнов Зыгыркольской рудной зоны, выявленных при участии авторов в последние годы на Северном фланге Тырныаузского рудного узла. Установлено длительное (с позднего палеозоя) развитие деформаций в пределах Гитче-Тырныаузского рудного поля, и что к формированию продуктивной на золото Зыгыркольской рудной зоны привели вертикальное растяжение и взбросо-сдвиговые деформации альпийского этапа. Выделены четыре участка развития золотоносных скарнов. Раскрыты характер и степень их золотоносности. Они определяются уровнем денудационного среза Зыгыркольской зоны, которая воздымается в северо-западном направлении под меньшим углом, чем возвышается рельеф, что приводит к уходу под рельеф оптимального рудоносного уровня. Оптимальным уровнем среза обладает Нижний участок, где наиболее золотоносные скарны выходят на земную поверхность. Минимальным уровнем среза обладает Перевальный участок, где продуктивные на золото скарны располагаются на 100?200 м ниже земной поверхности. Are described the geological conditions for localization of the gold-bearing Zygyrkol ore zone scarns, revealed with the participation of the authors in recent years on the northern flank of Tyrnyauz ore unit. Is established the prolonged (from the late Paleozoic period) development of deformations within the limits of Gitche-Tyrnyauz ore field, and that to shaping of productive to gold Zygyrkol ore zone gave vertical tension and the reverse fault-shift deformations of Alpine stage. Four sections of the development of gold-bearing scarns are isolated. Nature and degree of their gold content are opened. They are determined by the level of the Zygyrkol zone denudation shear, which rises up in the North Western direction hearth by smaller angle than is raised relief, which leads to the withdrawal under the relief of optimum ore-bearing level. The lower section, where the gold-bearing scarns leave to the earth’s surface, possesses the optimum level of shear. The crossing section, where the scarns productive to gold are located on 100?200 m lower than earth’s surface, possesses the minimum level of shear.

scholarly journals THE DUTCH PROGRAM OF INVESTIGATIONS ON STORM SURGES IN THE NORTH SEA

2011 ◽  
Vol 1 (5) ◽  
pp. 34
Author(s):  
J. B. Schijf
Keyword(s):  
The Netherlands ◽  
North Sea ◽  
Storm Surges ◽  
Water Levels ◽  
Wind Effects ◽  
Shallow Sea ◽  
The North ◽  
The North Sea ◽  
Western Germany ◽  
North Western

The North Sea is a shallow sea and therefore it is very sensitive to wind effects. As a result the water levels along the coasts are, in addition to the tidal oscillations subject to a considerable wind setup and exceptionally severe gales throughout history have been accompanied by inundations of the low-lying regions bordering the North Sea, in particular its southern part. No stretch of coast has suffered more than that belonging to the Netherlands and the adjacent parts of Belgium and North Western Germany. Several factors combine to bestow on us this doubtful privilege.

scholarly journals Conditions and triggers of landslides on flysch slopes in Istria, Croatia

2020 ◽  
Vol 40 (2) ◽  
pp. 77-87 ◽  
Author(s):  
Josip Rubinić ◽  
Željko Arbanas ◽  
Sanja Dugonjić Jovančević
Keyword(s):  
Early Spring ◽  
Water Levels ◽  
Rock Falls ◽  
Landslide Occurrence ◽  
The North ◽  
Rainfall Trends ◽  
Geological Conditions ◽  
North Eastern ◽  
North Eastern Part ◽  
Sliding Zone

The paper gives a review of conditions and triggers in which landslides occur on flysch slopes in central and northern Istria. The north-eastern part of the Istrian Peninsula, the so-called Gray Istria, consists of Paleogene flysch rock mass. Landslides in this area are usually triggered by heavy rainfall together with human activity which changes slope geometry and assists in retaining surface water in the sliding zone. Briefly, hydrogeological conditions in combination with ground water levels and pore water pressures increase, lead to numerous instability phenomena, during the long and continuous rainfall periods. Instabilities usually include small rotational and translational landslides, and it is seldom that debris flows and rock falls occur. Landslides are evenly evidenced in the first part of winter and the early spring time which corresponds to the second rainfall peak. The analyses performed based on landslide documentation and rainfall historical data, show rainfall trends associated with landslide occurrence. Depending on meteorological, hydrological and geological conditions, cumulative rainfall which triggered landslide activation varies inside a three-month period. The results presented show rainfall trends which serve as characteristic landslide triggers on flysch slopes in north-eastern part of Istria.

scholarly journals MONITORING OF FLOODING EVENTS ON THE RIVERS OF THE NORTH-WESTERN CAUCASUS IN 2014–2020

2021 ◽  
Vol 1 (6) ◽  
pp. 185-190
Author(s):  
I.V. Sheverdyaev ◽  
◽  
А.V. Kleschenkov ◽  
S.А. Misirov ◽  
Keyword(s):  
Water Levels ◽  
Winter Period ◽  
Floodplain Vegetation ◽  
The North ◽  
Northwestern Caucasus ◽  
Catchment Areas ◽  
Runoff Regime ◽  
Flooding Events ◽  
North Western ◽  
Automatic Level

The rivers of the Northwestern Caucasus between Anapa and Tuapse are characterized by a flood runoff regime. Floods leading to material damage occur on the rivers of the region every year. After the 2012 flood, a network of automatic level gauges is developing in the region, recording water levels every 10 minutes. During the expeditions of the SSC RAS in the winter period 2019-2020 the analysis of the installation sites of 69 level gauges was carried out. The features of level gauges influencing the collection of observations are identified: the installation options, floodplain vegetation, the features of the channel, floodplain and river valley. The analysis of the accumulated for 2014–2020 database of level observations on rivers with catchment areas from 1.4 km2 to 1245 km2 was carried out. 34 778 periods of growth, 70 135 periods of stagnation, 39 485 periods of decline and 42 032 gaps were identified. Of these, 3398 flood situations were considered. More than 100 flood events were recorded on 11 level gauges: on the rivers Abin, Shebsh, Psekups, Pshish (3 gauges), Nechepsukho, Dzhubga, Vulan, Pshada and Mezyb. Less than 10 flood situations were recorded on 14 level gauges. To increase the efficiency of the network of automatic level gauges, it is necessary to expand it to the watersheds between rivers Abin and Khable, as well as on Pshish on the northern macroslope and on the watersheds of Pshada, Nechepsukho and Tuapse on the southern macroslope.

scholarly journals Long-Term Variability in Ground Thermal State in Central Yakutia’s Tuymaada Valley

Land ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1231
Author(s):  
Stepan Prokopievich Varlamov ◽  
Yuri Borisovich Skachkov ◽  
Pavel Nikolaevich Skryabin
Keyword(s):  
Active Layer ◽  
Climate Warming ◽  
Thermal State ◽  
Snow Accumulation ◽  
Ground Temperature ◽  
Active Layer Thickness ◽  
Lena River ◽  
The North ◽  
Term Data

This paper presents the results of long-term temperature monitoring at the Yakutsk and Zeleny Lug stations, which are experimental sites, for the thermal state of valley permafrost landscapes under the conditions of modern climate warming. An analysis of the long-term data from meteorological stations in the region clearly showed one of the highest trends of increase in the mean annual air temperature in the north of Russia. Here, we established quantitative regularities in the long-term variability of the ground temperature at the bottom of the active layer and at zero amplitude. The dynamics of the ground temperature of the layer of zero amplitude during climate warming indicate the thermal stability of permafrost. The main regulating factor of the thermal state of grounds in permafrost landscapes is short-term fluctuations in the regime of snow accumulation. Active layer thickness is characterized by low interannual variability, weak climate warming responses, and insignificant trends. The results of studies of the thermal regime of soils can be extended to the same types of valley landscapes in the Lena River, and are a reliable basis for predicting heat transfer in natural and disturbed landscapes.

scholarly journals The role of geological conditions in the disintegration of historical structures on the escarpment of the Lower Vistula Valley, on the example of Chełmno (Poland)

2017 ◽  
Vol 12 (1) ◽  
pp. 83-91
Author(s):  
Ewa Labak-Mechowska ◽  
Michał Dąbrowski
Keyword(s):  
Geological Structure ◽  
Tourist Destination ◽  
Historical Structures ◽  
The North ◽  
Geological Conditions ◽  
North Western

Abstract Chełmno is a town in the north-western part of the Chełmno Lakeland. It is one of few towns in Poland to have fully preserved its medieval defensive walls. Its touristic and natural environs make it a popular tourist destination. The town’s location near the escarpment of the Vistula valley mean that the preserved historical structures (including the defensive walls) are under threat. A few years ago a buttress became detached and two sections of the defensive walls collapsed. One part was rebuilt (the site where the studies were conducted), while the second part remains unrestored. Bricks are also progressively coming away. This situation may be the result of several factors, although the authors claim that the most important are the geological structure and the wall foundations (which are shallow, at a depth of 1-2 m, with the wall having been built up higher in the 16th century).

scholarly journals Engineering and geological conditions of the north-western territory of Makhachkala due to flooding

2021 ◽  
pp. 45-54
Author(s):  
В.М. Кондаков ◽  
С.А. Мамаев ◽  
М.А. Мусаев ◽  
А.С. Мамаев
Keyword(s):  
Chemical Composition ◽  
Environmental Consequences ◽  
The North ◽  
Hydrogeological Parameters ◽  
Western Area ◽  
Geological Conditions ◽  
Caspian Lowland ◽  
Horizontal Type ◽  
North Western

Определение геоморфологических и геологических условий северо-западной площади г. Махачкалы, включая Новолакский район (Новострой), в связи с процессами засоления, осолонцевания и подтопления сельскохозяйственных земель. В настоящее время город интенсивно расширяется во все стороны. Особенно актуально изучение северо-западной территории г. Махачкалы в связи с подтоплением. Район относится к Прикаспийской низменности с отрицательными отметками рельефа. Отсутствие исследований по указанным проблемам может привести к нежелательным материальным и экологическим последствиям. В связи с подтоплением изменяются и несущие способности грунтов. Изменяются сейсмоакустические свойства грунтов, т.е. скорости распространения продольных (Vp) и поперечных (Vs) волн, а также соответствующие коэффициенты и декременты их поглощения. Цель работы. Определить границы слабо дренированных и весьма слабо дренированных зон, которые выявляют барражные участки территории, и гидрогеологические районы в зависимости от водопроводимости составных верхней и нижней толщ грунтов. Методы исследований. Сбор базы данных инженерно-геологических изысканий по химическому составу грунтовых вод и литологии покровных толщ грунтов. Сбор гидрогеологических параметров разных типов грунтов и гранулометрического состава песков целью интерпретации их фильтрационных свойств. Определение уклона рельефа местности с целью выявления зон дренированности территории. Результаты работы. Представлены таблицы химического состава грунтовых вод по 19-ти объектам и гидрогеологических условий площади по данным инженерно-геологических изысканий по 39-ти объектам, в том числе глубины залегания грунтовых вод, типа грунтов по сейсмичности, глубины залегания коренных пород, трех таксонов гидрогеологических районов, уклонов рельефа. Для выделенных гидрогеологических районов: для ГР-1 рекомендуется горизонтальный тип дренажа, для ГР-2 – вертикальный или комбинированный типы дренажа, для ГР-3 – подземный дренаж не эффективен. Указано о необходимости сейсмического микрорайонирования не только исследованного района, но и всего города Махачкалы, с перспективой дальнейшей застройки. Determination of the geomorphological and geological conditions of the north-western area of Makhachkala, including the Novolaksky district (Novostroy), in connection with the processes of salinization, alkalinization and flooding of agricultural lands. Currently, the city is intensively expanding in all directions. Particularly interesting is the study area of ​​the northwestern territory of Makhachkala due to flooding. It belongs to the Caspian lowland with negative relief marks. Lack of research on these problems can lead to undesirable material and environmental consequences. Due to flooding, the bearing capacity of the soil also changes. The seismoacoustic properties of soils change, i.e. the velocities of propagation of longitudinal (Vp) and transverse (Vs) waves, as well as the corresponding coefficients and decrements of their absorption. Aim.Determine the boundaries of poorly drained and very poorly drained zones, which reveal barrage areas of the territory, and hydrogeological areas, depending on the water permeability of the composite upper and lower soil strata. Methods. Collecting a database of geotechnical surveys on the chemical composition of groundwater and lithology of cover layers of soils. Collecting hydrogeological parameters of different types of soils and granulometric composition of sands in order to interpret their filtration properties. Determination of the slope of the terrain in order to identify the drainage zones of the territory. Results.Presented are tables of the chemical composition of groundwater for 19 objects and hydrogeological conditions of the area according to engineering and geological surveys for 39 objects, including the depth of groundwater, the type of soil in terms of seismicity, the depth of bedrock, three taxa of hydrogeological regions, slopes of the relief. For the selected hydrogeological regions: GR-1 - a horizontal type of drainage is recommended, for GR-2 - vertical or combined types of drainage, for GR-3 - underground drainage is not effective. It is indicated that it is necessary to seismic microzoning not only of the investigated area, but of the entire city of Makhachkala with the prospect of further development.

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