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Morphology of valley networks
Kusák, Michal ; Křížek, Marek (advisor) ; Hartvich, Filip (referee)
This bachelor thesis is engaged in the juxtaposition and different methods account of valley networks. Thanks to the background research of the late published literature, there are known a lot of types of valley network, which result in various types of relief and the criteria by which can the different types of valley networks be identified and distinguished from other types of valley networks. Methods of characterizing the valley networks are used to describe the valley of the same type of networks in different areas, respectively allow their comparison. In the interested area of CHKO Kokořínsko, there were studied the valley network order, the type of the valley network, the bifurcation ratio, connected of valley network, the fractal dimension, the valley network homogenity and the allometry of the valley of some parts. Valley networks in the studied areas of Pšovka and Liběchovka were identified as trellis and valley network of studied area of Vlhošt was described as a radial type of valley network with elements of annular valley network.
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Morphometric characteristics of valley nets in the Blue Nile basin in the Ethiopian highlands
Kusák, Michal ; Křížek, Marek (advisor) ; Hartvich, Filip (referee)
The Blue Nile basin has diverse geological history, eg. repeated sea transgression and regression, Tertiary and Quaternary vulcanism, extensional faults in rift system, or area uplift (in the last 29 million years), which caused cutting of the rivers to their subsoil and creating deep gorges (Kazmin, 1975; Pik et al., 2003; Beyne, Abdelsalam, 2005, 2006; Gani et al., 2007; Gani et al., 2009; Wolela, 2010). This paper deals with classification and morphometric features of the Blue Nile valley nets in the Ethiopian highlands. Dendritic and trellis valley nets predominated in the Blue Nile basin. Trellis and rectangular valley nets predominated in the eastern part of the studied area, i.e. the upper part of the drainage area, and dendritic valley nets predominated in the western part of the studied area, i.e. the lower part of the drainage area. Parallel valley nets were located on the border of the studied area, i.e. the watershed or on the slopes of Cenozoic shield volcanoes. Annular valley nets did not occur in the Blue Nile basin. Valley nets were characterized by specific topologic and geometric features: 1) the Gravelius order system; 2) the bifurcation ratio of various order valleys, 3) the average length of various order valleys, 4) the average length-order ratio of various order valleys, 5)...
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Morphostructural analysis of Ethiopian Highland based on remote sensing
Kusák, Michal ; Vilímek, Vít (advisor) ; Klimeš, Jan (referee) ; Novotný, Ján (referee)
- Morphostructural analysis of Ethiopian Highland based on remote sensing The morphometric analysis of lineaments, valleys and signs of erosion taken from a digital elevation model (DEM) made it possible to not only confirm most of the conclusions of the morphotectonic development of the area from the previously published results of structural, petrological, tectonic and geochronological analyses from the Ethiopian Highlands, but to also to expand our knowledge by applying several new hypotheses. Faults, lineaments and valleys are predominantly oriented in a direction compatible to the published concepts of the tectonic development of the area. Overall, the most abundant NE-SW and NNE-SSW lines reflect a change of extension from a NW-SE to WNW-ESE direction during the Pliocene (~40ř rotation), in relation to the creation and development of the Main Ethiopian Rift. The most pronounced morphological manifestations of the extension of the MER and western Afar during the Quaternary are confined to the borders of the MER, and the maximum SOLR values indicate a very short-lived effect of the stress field on the development of the landscape. The directions of the Pre-Neogene rift structures to the NW-SE and WNW-ESE are compatible with the oldest elements of the current landscape, i.e. the most developed...
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Morphometric characteristics of valley nets in the Blue Nile basin in the Ethiopian highlands
Kusák, Michal
- Morphometric characteristics of valley nets in the Blue Nile basin in the Ethiopian highlands The Blue Nile basin has diverse geological history, eg. repeated sea transgression and regression, Tertiary and Quaternary vulcanism, extensional faults in rift system, or area uplift (in the last 29 million years), which caused cutting of the rivers to their subsoil and creating deep gorges (Kazmin, 1975; Pik et al., 2003; Beyne, Abdelsalam, 2005, 2006; Gani et al., 2007; Gani et al., 2009; Wolela, 2010). This paper deals with classification and morphometric features of the Blue Nile valley nets in the Ethiopian highlands. Dendritic and trellis valley nets predominated in the Blue Nile basin. Trellis and rectangular valley nets predominated in the eastern part of the studied area, i.e. the upper part of the drainage area, and dendritic valley nets predominated in the western part of the studied area, i.e. the lower part of the drainage area. Parallel valley nets were located on the border of the studied area, i.e. the watershed or on the slopes of Cenozoic shield volcanoes. Annular valley nets did not occur in the Blue Nile basin. Valley nets were characterized by specific topologic and geometric features: 1) the Gravelius order system; 2) the bifurcation ratio of various order valleys, 3) the average...
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Morphostructural analysis of Ethiopian Highland based on remote sensing
Kusák, Michal ; Vilímek, Vít (advisor) ; Klimeš, Jan (referee) ; Novotný, Ján (referee)
- Morphostructural analysis of Ethiopian Highland based on remote sensing The morphometric analysis of lineaments, valleys and signs of erosion taken from a digital elevation model (DEM) made it possible to not only confirm most of the conclusions of the morphotectonic development of the area from the previously published results of structural, petrological, tectonic and geochronological analyses from the Ethiopian Highlands, but to also to expand our knowledge by applying several new hypotheses. Faults, lineaments and valleys are predominantly oriented in a direction compatible to the published concepts of the tectonic development of the area. Overall, the most abundant NE-SW and NNE-SSW lines reflect a change of extension from a NW-SE to WNW-ESE direction during the Pliocene (~40ř rotation), in relation to the creation and development of the Main Ethiopian Rift. The most pronounced morphological manifestations of the extension of the MER and western Afar during the Quaternary are confined to the borders of the MER, and the maximum SOLR values indicate a very short-lived effect of the stress field on the development of the landscape. The directions of the Pre-Neogene rift structures to the NW-SE and WNW-ESE are compatible with the oldest elements of the current landscape, i.e. the most developed...
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Morphometric characteristics of valley nets in the Blue Nile basin in the Ethiopian highlands
Kusák, Michal
- Morphometric characteristics of valley nets in the Blue Nile basin in the Ethiopian highlands The Blue Nile basin has diverse geological history, eg. repeated sea transgression and regression, Tertiary and Quaternary vulcanism, extensional faults in rift system, or area uplift (in the last 29 million years), which caused cutting of the rivers to their subsoil and creating deep gorges (Kazmin, 1975; Pik et al., 2003; Beyne, Abdelsalam, 2005, 2006; Gani et al., 2007; Gani et al., 2009; Wolela, 2010). This paper deals with classification and morphometric features of the Blue Nile valley nets in the Ethiopian highlands. Dendritic and trellis valley nets predominated in the Blue Nile basin. Trellis and rectangular valley nets predominated in the eastern part of the studied area, i.e. the upper part of the drainage area, and dendritic valley nets predominated in the western part of the studied area, i.e. the lower part of the drainage area. Parallel valley nets were located on the border of the studied area, i.e. the watershed or on the slopes of Cenozoic shield volcanoes. Annular valley nets did not occur in the Blue Nile basin. Valley nets were characterized by specific topologic and geometric features: 1) the Gravelius order system; 2) the bifurcation ratio of various order valleys, 3) the average...
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Classification of landslides in selected areas of the Ethiopian Highland
Schreiberová, Kateřina ; Vilímek, Vít (advisor) ; Kusák, Michal (referee)
CLASSIFICATION OF LANDSLIDES IN SELECTED AREAS OF THE ETHIOPIAN HIGHLAND ABSTRACT This thesis is an introduction to landslides and how they are triggered and occur on the tectonic pattern in the Ethiopian Highland, which borders with the Great Rift Valley. Included in this thesis are types of classifications of landslides. Especially on base of the main mechanics of mass wasting movement are the landslides classified in investigation part. The methodology of landslide investigation is based on remote sensing. Further discussed is the methodology used in landslide investigation in general, as well as the causes of downhill movements in landslide prone areas of the Ethiopian Highland. Keywords: landslides, Ethiopian Highland, remote sensing, elevation
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The susceptibility analysis of slope movements in the Jemma River basin (Ethiopian Highland)
Maca, Vít ; Vilímek, Vít (advisor) ; Kusák, Michal (referee)
Ethiopia like other developing countries depends on domestic agricultural production, struggling with infrastructure and healthcare is also at a low level. Among these factors there is also added impact of catastrophic natural processes. Landslides in this area have caused enormous material damage and also human deaths. Effects of those losses are huge and locals are dealing with them difficuly. Therefore, prevention should be a priority concern. In theoretical part the basic facts about modeling and simulation of landslides susceptibility is presented. Those facts are complemented with specific researches from Ethiopian highlands. Furthermore, it describes the methodology that was used. It compares the real distribution of slope movements against the expected occurrence across the classes of input layers. An essential part of the model is mapping work, supported with terrain work, during which 242 landslides was mapped. Model parameters are: slope, altitude, lithology, land cover, distance from geological boundary and distance to river. Slope was determined as most significant factor. Used methodology is universally applicable and the results it generates match reality well. Key words: slope movements, natural hazards, susceptibility analysis, geomorphology, Ethiopian Highland
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Morphometric characteristics of valley nets in the Blue Nile basin in the Ethiopian highlands
Kusák, Michal ; Křížek, Marek (advisor) ; Hartvich, Filip (referee)
The Blue Nile basin has diverse geological history, eg. repeated sea transgression and regression, Tertiary and Quaternary vulcanism, extensional faults in rift system, or area uplift (in the last 29 million years), which caused cutting of the rivers to their subsoil and creating deep gorges (Kazmin, 1975; Pik et al., 2003; Beyne, Abdelsalam, 2005, 2006; Gani et al., 2007; Gani et al., 2009; Wolela, 2010). This paper deals with classification and morphometric features of the Blue Nile valley nets in the Ethiopian highlands. Dendritic and trellis valley nets predominated in the Blue Nile basin. Trellis and rectangular valley nets predominated in the eastern part of the studied area, i.e. the upper part of the drainage area, and dendritic valley nets predominated in the western part of the studied area, i.e. the lower part of the drainage area. Parallel valley nets were located on the border of the studied area, i.e. the watershed or on the slopes of Cenozoic shield volcanoes. Annular valley nets did not occur in the Blue Nile basin. Valley nets were characterized by specific topologic and geometric features: 1) the Gravelius order system; 2) the bifurcation ratio of various order valleys, 3) the average length of various order valleys, 4) the average length-order ratio of various order valleys, 5)...
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Morphology of valley networks
Kusák, Michal ; Křížek, Marek (advisor) ; Hartvich, Filip (referee)
This bachelor thesis is engaged in the juxtaposition and different methods account of valley networks. Thanks to the background research of the late published literature, there are known a lot of types of valley network, which result in various types of relief and the criteria by which can the different types of valley networks be identified and distinguished from other types of valley networks. Methods of characterizing the valley networks are used to describe the valley of the same type of networks in different areas, respectively allow their comparison. In the interested area of CHKO Kokořínsko, there were studied the valley network order, the type of the valley network, the bifurcation ratio, connected of valley network, the fractal dimension, the valley network homogenity and the allometry of the valley of some parts. Valley networks in the studied areas of Pšovka and Liběchovka were identified as trellis and valley network of studied area of Vlhošt was described as a radial type of valley network with elements of annular valley network.
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