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Teleseismic earthquake occurrence and subduction-induced volcanic activity along island arcs
Kuna, Václav ; Špičák, Aleš (advisor) ; Čížková, Hana (referee)
This diploma thesis studies seismo-volcanic interactions at convergent plate margins. Its aim is to establish a statistical apparatus appropriate for analyzing seismicity patterns be- neath volcanoes. At the beginning, the thesis summarizes basic concepts of volcanism at convergent plate margins and basic seismological issues. The thesis takes advantage of so called EHB catalogue of hypocentral determinations based on data of the International Seimological Center. The analysis of combined space-time correlation dimension of the EHB catalogue established limits for a definition of seismic sequences related to co-seismic as well as post-seismic stress transfer mechanisms. The analysis of b-value of the Guten- berg-Richter law was carried out to estimate degree of heterogeneity of rock environment. Seismicity pattern beneath subduction-related volcanoes at 14 island arcs was studied by means of seismic sequence density analysis and the b-value analysis. The thesis concentrat- ed on submarine portions of the volcanic arcs, the magmatic/volcanic activity of which is poorly understood. We constrained areas with specific seismicity patterns and distinct sea- floor morphology in order to find potential volcanic structures. Five areas with specific seismicity pattern and pronounced morphological structure...
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Joule heating of Mercury
Peisar, Ondřej ; Velímský, Jakub (advisor) ; Čížková, Hana (referee)
In this paper we investigate influence of the interior and exterior magnetic fields on mantle heating of Mercury. Exterior field is induced by currents in the magnetosphere, interior field is generated by dynamo deep in the planetary core, whose outer layer is stably stratified. After summarization of basic facts about Mercury we derive a formula for magnetic field on the surface and on the inner boundary. Afterwards we investigate the influence of conductivity estimates and periods on heat production in the mantle. We found out that for expected conductivities (iron core, silicate mantle) magnetic field doesn't have any influence on mantle convection.
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Regional models of lithospheric subduction
Androvičová, Adela ; Čížková, Hana (advisor) ; Běhounková, Marie (referee)
Processes within subduction zones have major influence on the plate dynamics and mantle convection. Subduction process is influenced by a combination of many parameters and there is no simple global relationship between the resulting slab geometry and deformation and any specic subduction parameter. In the present work we perform a parametric study of the slab dynamics in a two-dimensional model with composite rheology including diffusion creep, dislocation creep and stress limiting rheology or Peierls creep. In our model, the separation of the subducting and overriding plates is ensured by a layer of a low viscosity material. We are particularly interested in the effect of the contact of subducting and overriding plate on the plate geometry in the upper mantle. We also study the influence of a surface boundary condition and the rheologic parameters of the plate. Model results are applied to the Kermadec subduction zone. We show that the model that best fits the observed morphology and plate velocities is the model with viscosity of crust of 1020 Pa.s, yield stress of 108 Pa and with a viscosity jump by a factor of 10 at the depth of 660 km.
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Domestic Violence on Seniors
Musilová, Ornella ; Dočkal, Jan (advisor) ; Čížková, Hana (referee)
The bachelor thesis is focused on problem of domestic violence on seniors in the Czech Republic. The aim of thesis is describe and analyze fenomen of domestic violence on seniors, shows reasons, consequences and try to propose some solutions. First chapter is concerned with the definition of senior and ageing. Second chapter deals with domestic violence on seniors, forms, causes and censequences for seniors. Third chapter shows posibilities of prevention and solutions of domestic violence for elder people, especially legislation, action plan and related social services. Fourt chapter describes organization Život 90 and its project, which could be one of the posibility how resolves the domestic violence of seniors. It includes 5 case studies, which concerning domestic violence on seniors. There are presented suggestion for posible solutions of domestic violence on the basis of prevention options in the last chapter. Powered by TCPDF (www.tcpdf.org)
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