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Dynamic of evolution and hazardousness of lakes in the Cordillera Blanca (Peru)
Emmer, Adam ; Vilímek, Vít (advisor) ; Šobr, Miroslav (referee) ; Haeberli, Wilfried (referee)
Adam Emmer: Dynamic of evolution and hazardousness of lakes in the Cordillera Blanca (Peru) Abstract: High mountain environment of the Cordillera Blanca (Peru) is undergoing prespicious (goe)environmantal changes such as glacier retreat and associated formation and evolution of lakes. Glacial lakes may represent a threat for the society in case of sudden release of (part of) retained water ("glacial lake outburst flood"; GLOF). Reliable identification of hazardous lakes is a key persumption of effective GLOF risk management. The fundamental part of this thesis lies in creation of new method for assessing susceptibility of lakes to outburst floods, reflecting regional specifics of these events in the study area (preconditions, causes and mechanisms) and unsuitability of existing approaches revealed in previous research. Newly created method take into account five scenarios of GLOFs, which are assessed separately, using the combination of decision trees allowing integration of qualitative and quantitative characteristics (an overall number of 17 characteristics of the dam, lake and lake surrounding enter the assessment procedure). Thus, identification of specific causes and mechanisms is enabled. The method was verified by assessing susceptibility of 20 lakes, of which 10 produced GLOFs in past (pre-flood...
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Geomorphological evidence of neotectonic activity along Cordillera Blanca fault zone, Peru
Masák, Ondřej ; Vilímek, Vít (advisor) ; Stemberk, Josef (referee)
Southwest base of Cordillera Blanca mts. in South American Ands belongs to the most tectonically active fault zones. The core of this thesis was making of a detailed geomorphological map based on remote sensing satellite images for the purpose of analysis of direct and indirect manifestations of neotectonics. The greatest emphasis was placed on morphological manifestations of tectonics movements which are fault scarps facets and vertical fault steps deforming other shapes of relief - e.g. lateral moraines, dejection cones. Vertical steps reach from a few meters to tens of meters (max. 60 m) according to the age of influenced landform. Evaluation of measurements from deformometr from locality Pitec shows main trends of movements - moderate rise of massif, slow opening of fault plane and negligible left-lateral slip. Calculation of mountain-front sinuosity index, whose values were found relatively low, confirms high tectonic activity of fault zone. Analysis of longitudinal stream profiles hasn't showed presence of knick-points in the place of crossing with fault zone. Non-continuous process of lifting movements, whose interval is estimated at 1ka to 3ka (while the very last 2ka has been in relative tectonic calm), could be a possible explanation. Deep erosion of water streams wiped the tectonics...
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Detection of Equilibrium Line Altitude (ELA) Changes from Remote Sensing Data; Case Study from the Cordillera Blanca, Peru
Paraj, Zsolt ; Potůčková, Markéta (advisor) ; Kropáček, Jan (referee)
The aim of this diploma thesis is to monitor glacier change in the Cordillera Blanca in the period from 1987 to 2014. This diploma thesis focuses on three mountains and eleven glaciers in the northern part of the Cordillera Blanca. The input data consist of 29 Landsat scenes (Landsat 4,5,7 and 8) and the ASTER global digital elevation model version 2. Semi-automatic classification algorithm is created based on threshold values detected by spectral analyses of selected land cover types in the Cordillera Blanca. Additionally, the mean snowline (equilibrium line) altitude change is computed for all of the three mountains and eleven glaciers. Besides, glacier change depending on slope and aspect is evaluated. The results of this diploma thesis are presented in maps, tables and charts. The results of the classification are compared with the GLIMS Glacier Database and the field measurements provided by Adam Emmer, MSc. Finally, the advantages and disadvantages of the new Landsat 8 satellite sensor are discussed. Key words: Remote sensing, Landsat, classification, ice and snow detection, ELA, Cordillera Blanca
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The analysis of geomorphological pronunciation of neotectonics on Cordillera Blanca faults
Burkytová, Šárka ; Vilímek, Vít (advisor) ; Klimeš, Jan (referee)
The study deals with analysis of of geomorphological pronunciation of neotectonics along the based on fault slope in the South American Cordillera Blanca range. It contains research about physical-geographycal characteristic of the mountain range with the focus on geology, geomorphology and the theoretical concept of forms on fault slopes and neotectonic acitivity. In the practical part of the thesis, the selected area of the mountain range was mapped using Google Earth imagery. On the base of created map the forms associated with the active tectonic uplift of the Cordillera Blanca were analyzed and invented. Then the longitudinal profiles of rivers that flow across the fault zone were created and analyzed from the digital terrain model. The block structure of the mountain range was analyzed too. Keywords Cordillera Blanca, geomorphology, morphometry, neotectonics, Peru
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Dynamic of evolution and hazardousness of lakes in the Cordillera Blanca (Peru)
Emmer, Adam ; Vilímek, Vít (advisor) ; Šobr, Miroslav (referee) ; Haeberli, Wilfried (referee)
Adam Emmer: Dynamic of evolution and hazardousness of lakes in the Cordillera Blanca (Peru) Abstract: High mountain environment of the Cordillera Blanca (Peru) is undergoing prespicious (goe)environmantal changes such as glacier retreat and associated formation and evolution of lakes. Glacial lakes may represent a threat for the society in case of sudden release of (part of) retained water ("glacial lake outburst flood"; GLOF). Reliable identification of hazardous lakes is a key persumption of effective GLOF risk management. The fundamental part of this thesis lies in creation of new method for assessing susceptibility of lakes to outburst floods, reflecting regional specifics of these events in the study area (preconditions, causes and mechanisms) and unsuitability of existing approaches revealed in previous research. Newly created method take into account five scenarios of GLOFs, which are assessed separately, using the combination of decision trees allowing integration of qualitative and quantitative characteristics (an overall number of 17 characteristics of the dam, lake and lake surrounding enter the assessment procedure). Thus, identification of specific causes and mechanisms is enabled. The method was verified by assessing susceptibility of 20 lakes, of which 10 produced GLOFs in past (pre-flood...
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Detection of Equilibrium Line Altitude (ELA) Changes from Remote Sensing Data; Case Study from the Cordillera Blanca, Peru
Paraj, Zsolt ; Potůčková, Markéta (advisor) ; Kropáček, Jan (referee)
The aim of this diploma thesis is to monitor glacier change in the Cordillera Blanca in the period from 1987 to 2014. This diploma thesis focuses on three mountains and eleven glaciers in the northern part of the Cordillera Blanca. The input data consist of 29 Landsat scenes (Landsat 4,5,7 and 8) and the ASTER global digital elevation model version 2. Semi-automatic classification algorithm is created based on threshold values detected by spectral analyses of selected land cover types in the Cordillera Blanca. Additionally, the mean snowline (equilibrium line) altitude change is computed for all of the three mountains and eleven glaciers. Besides, glacier change depending on slope and aspect is evaluated. The results of this diploma thesis are presented in maps, tables and charts. The results of the classification are compared with the GLIMS Glacier Database and the field measurements provided by Adam Emmer, MSc. Finally, the advantages and disadvantages of the new Landsat 8 satellite sensor are discussed. Key words: Remote sensing, Landsat, classification, ice and snow detection, ELA, Cordillera Blanca
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Analysis of the zone of recent deglaciation, Cordillera Blanca, Peru
Juřicová, Anna ; Vilímek, Vít (advisor) ; Burda, Jan (referee)
The master thesis is focused on analysis of the zone of recent deglaciation in the Cordillera Blanca, Peru. Geomorphological mapping that had been realized based on interpretation of the satellite data and field reconnaissance was used for interpretation of main geomorphological features and processes of the selected glacial valleys. Glaciofluvial processes and mass movements are the main processes that affected the relief in the recent period. Major differences in landforms presence and distribution have been found between the studied valleys. The main differences are between valleys located on the western side and eastern side of the mountains. Number of different sediments of different types have been identified on the western side, whereas no evidence of such sediments was found on the eastern side. These differences are probably caused by differences in geology and climatic conditions. Finally, a general sediment flux model on the information gained from the geomorfologic analysis has been created and shows space distribution of geomorphological features and processes. The analyses of the satellite data show different visual characteristics of the rocks, which has been confirmed during field works using Schmidt Hammer method. The results suggest that the rocks that have been exposed for longer time due...
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The analysis of supraglacial lakes: case study from Cordillera Blanca, Peru
Baťka, Jan ; Vilímek, Vít (advisor) ; Emmer, Adam (referee)
The analysis of supraglacial lakes: case study from the Cordillera Blanca, Peru ABSTRACT: Supraglacial lakes play an important role in the processes of glacier ablation. Through their expansion, a proglacial lake that usually poses significant threat to downvalley located areas can form. Such formation of proglacial lakes also took place and was well described in the Peruvian Cordillera Blanca (e.g. Laguna 513). However, there are only few studies relating to supraglacial lakes of this range. First in this thesis, based on the research of the scientific literature, the factors influencing supraglacial lakes' development and some of the limnological characteristics are listed in detail. Second, recent evolution (2003-2014) of supraglacial lakes of the Cordillera Blanca is analysed on the sample of 13 glaciers. The results show that the development of supraglacial lakes is influenced by their frequent destructions (because of outbursts and/or rapid accumulation of debris in the basin). In addition, the expansion of the extent of supraglacial lakes on a glacier tongue is strongly controlled by surface gradient. Keywords: glaciers, supraglacial lakes, Cordillera Blanca, Peru
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The Glacial Retreat in the Cordillera Blanca since the Littel Ice Age
Dobíhal, Michal ; Vilímek, Vít (advisor) ; Emmer, Adam (referee)
Michal Dobíhal Studijní program: Geografie Studijní obor: Fyzická geografie a geoinformatika Bakalářská práce Vedoucí práce, školitel: Doc. RNDr. Vít Vilímek, CSc. The glacial retreat in the Cordillera Blanca since the Little Ice Age ABSTRACT: The term Little Ice Age refers to a cooling period of time, as a result of this cooling mountain glaciers experienced significant advance in many parts of the world. Conventionally, the period between the 16th century and the middle of the 19th century is stated for the Little Ice Age, but its course and time placement differs in individual world regions. Based on research of scientific literature, this thesis aims at describing correct time placement of the Little Ice Age in the southamerican mountain range Cordillera Blanca and the expanse of the glacier retreat since its maximum till the present. Methods of lichenometry used for dating "Little Ice Age" moraines are mentioned as well. In the analytical part, the area of the glaciation of selected glaciers from the Little Ice Age maximum and from the present is compared using polygon measurement and satellite images. The extrapolation of this method is subsequently made on other selected glaciers, whose moraines have not been dated yet. Keywords: Cordillera Blanca, Little Ice Age, glacial retreat, moraine, lichenometry
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Potential hazardousness of selected moraine-dammed lakes in the Cordillera Blanca, Peru
Emmer, Adam ; Vilímek, Vít (advisor) ; Klimeš, Jan (referee)
Adam Emmer: Potential hazardousness of selected moraine-dammed lakes in the Cordillera Blanca, Peru ABSTRACT: This work is devided into the two parts. Firs part reviews contemporary methods of assessment of potential hazardousness for moraine-dammed lakes (eight qualitative methods and three quantitative methods). Second part has two main aims: 1) Assessment of potential hazardousness of seven selected moraine-dammed lakes in the Cordillera Blanca, and 2) Analysis of suitability of these methods for use in this region. Required input data for potential hazardousness assessment were gained from analysis of remotely sensed photographs, research papers of INRENA/ANA institute (Huaráz), and from fieldwork realized in 2012. Ten methods of potential hazardousness assessment were applied on seven studied moraine-dammed lakes. There are no significant differences in results obtained in each method. These results showed, that potentially most hazardous lake is that of Arhueycocha, followed by Palcacocha. On the other hand potentially less hazardous lake is that of Rajucolta. Based on analysis of regional specific of causes and mechanisms of glacial lake outburst floods from moraine-dammed lakes in Cordillera Blanca, five groups of characteristics which reflect these regional specifics were merged: A) possibility of...
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