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Jeziora Parku Narodowego Pojezierze Smoleńskie (Rosja)

Skrzypczak Robert

Przegląd Geologiczny

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2020

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Vol. 68, nr 1

50--53

EN

The Smolensk Lakeland National Park is situated north of Smoleńsk in the NW Russia. Its morphology is associated with the last European ice sheet: glacial erosion and accumulation, glacial water activity, locally with the so-called thermokarst process or karst in the strict sense. The post-glacial morphological depressions are filled with lake waters. The most interesting lakes are: Chistik, Mutnoye, Balshoye and Maloye Striechnoye, Glubokoye, Dolgoye, Krugloye, Pietrovskoye, Bukino, Gorodishche, Svyatec, Sapsho, Polovia, Gniloye, Rytoye, Dgo, Shchuch’ye, Baklanovskoye, Bachovskoye, Vervizhskoye, Pal’tsevskoye and Bieloye. The Smolensk Lakeland National Park is one of a few territories in Europe where the beauty of nature and landscapes dominate the long-standing human presence. Nowadays, there are a few residents, a growing number of patients, seasonal campers and tourists in the park area.

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Studying permafrost by integrating satellite and in situ data in the northern high‑latitude regions

Gido Nureldin A. A., Bagherbandi Mohammad, Sjöberg Lars E., Tenzer Robert

Acta Geophysica

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2019

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Vol. 67, no. 2

721--734

EN

There is an exceptional opportunity of achieving simultaneous and complementary data from a multitude of geoscience and environmental near-earth orbiting artificial satellites to study phenomena related to the climate change. These satellite missions provide the information about the various phenomena, such as sea level change, ice melting, soil moisture variation, temperature changes and earth surface deformations. In this study, we focus on permafrost thawing and its associated gravity change (in terms of the groundwater storage), and organic material changes using the gravity recovery and climate experiment (GRACE) data and other satellite- and ground-based observations. The estimation of permafrost changes requires combining information from various sources, particularly using the gravity field change, surface temperature change, and glacial isostatic adjustment. The most significant factor for a careful monitoring of the permafrost thawing is the fact that this process could be responsible for releasing an additional enormous amount of greenhouse gases emitted to the atmosphere, most importantly to mention carbon dioxide (CO2) and methane that are currently stored in the frozen ground. The results of a preliminary numerical analysis reveal a possible existence of a high correlation between the secular trends of greenhouse gases (CO2), temperature and equivalent water thickness (in permafrost active layer) in the selected regions. Furthermore, according to our estimates based on processing the GRACE data, the groundwater storage attributed due to permafrost thawing increased at the annual rates of 3.4, 3.8, 4.4 and 4.0 cm, respectively, in Siberia, North Alaska and Canada (Yukon and Hudson Bay). Despite a rather preliminary character of our results, these findings indicate that the methodology developed and applied in this study should be further improved by incorporating the in situ permafrost measurements.

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Numerical Simulation of Response Characteristics of Audio-magnetotelluric for Gas Hydrate in the Qilian Mountain Permafrost, China

Xiao K., Zou Ch., Yu Ch., Pi J.

Acta Geophysica

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2015

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Vol. 63, no. 5

1368--1404

EN

Audio-magnetotelluric (AMT) method is a kind of frequencydomain sounding technique, which can be applied to gas hydrate prospecting and assessments in the permafrost region due to its high frequency band. Based on the geological conditions of gas hydrate reservoir in the Qilian Mountain permafrost, by establishing high-resistance abnormal model for gas hydrate and carrying out numerical simulation using finite element method (FEM) and nonlinear conjugate gradient (NLCG) method, this paper analyzed the application range of AMT method and the best acquisition parameters setting scheme. When porosity of gas hydrate reservoir is less than 5%, gas hydrate saturation is greater than 70%, occurrence scale is less than 50 m, or bury depth is greater than 500 m, AMT technique cannot identify and delineate the favorable gas hydrate reservoir. Survey line should be more than twice the length of probable occurrence scale, while tripling the length will make the best result. The number of stations should be no less than 6, and 11 stations are optimal. At the high frequency section (10~1000 Hz), there should be no less than 3 frequency points, 4 being the best number.