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Contribution to the tectonic interpretation of the seismicity pattern of Banda Arc, SE Asia
Matějková, Radka ; Špičák, Aleš (advisor) ; Zahradník, Jiří (referee)
i Abstract Contribution to the tectonic interpretation of the seismicity pattern of the Banda Arc, Southeast Asia Tectonic structure of the Banda Arc in Southeast Asia is regarded as an extremely complicated unit as it is situated at the intersection of four lithospheric plates: Eurasian, Indo-Australian, Pacific, and Philippine. The present-day tectonic regime is arc-continent collision. The seismotectonic pattern of the Banda Arc region was studied using global seismological data. Relocated EHB hypocentral determinations for the period 1964 - 2004 and fault plane solutions of Harvard CMT data for the period 1976 - 2004 have been used. The analysis of spatial distribution of earthquake foci and the analysis of focal mechanisms enabled to distinguish the foci belonging to the Wadati-Benioff zone of the subducting plate from those occurring in the overriding plate. The analysis discriminated two opposite dipping subduction zones - southern Banda subduction and northern Seram subduction. The following specific phenomena were observed in the Wadati-Benioff zone: (i) unusual lateral bent of the Wadati-Benioff zone of the southern Banda subduction, (ii) intermediate- depth (100 - 220 km), vertically situated domain of the highest seismicity within the Wadati-Benioff zone of the southern Banda subduction, (iii)...
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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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Subduction factory interaction of subduction-related magma with the overlying lithosperic wedge
Kuna, Václav ; Špičák, Aleš (advisor) ; Hrubcová, Pavla (referee)
III Abstract The world's largest earthquakes, the most destructive tsunamis and the most explosive vol- canism are generated at subduction zones at convergent plate margins. Despite of high societal and economic importance of these areas, there are still some poorly understood processes, such as the process of magma generation and ascent to the Earth surface. This thesis contributes to the solution of the problem of location of source areas of calc-alkaline magma and its migration. It consists of two parts: in the first one, the phenomenon of vol- canism at convergent plate margins and seismological background are described, while the second part explores structures in the lithosphere beneath volcanoes in the broader region of the Banda Arc (Indonesia). For the purposes of the research, the ISC hypocentral de- terminations based on data from the global seismic network, relocated by a procedure of Engdahl et al. and collected in the so called EHB database were used. The analyses of spa- tial, time and magnitude dependencies in the dataset of earthquakes occurring within the Banda Arc area enabled us to formulate several conclusions: The occurrences of strong teleseismically recorded earthquakes in the lithospheric wedge beneath volcanoes suggests that the respective rock medium is not partially melted....
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Structural control of the 2011 Mw 9.0 Tohoku-Oki earthquake and its relation to the overall seismicity of Honshu
Haislová, Radka ; Špičák, Aleš (advisor) ; Málek, Jiří (referee)
The 2011 March 11 Tohoku-Oki earthquake with moment magnitude of 9.0 east of Honshu, Japan, has been the fourth strongest event in the era of instrumental seismology. This thesis is focussed on a detailed analysis of earthquake distribution in time and space in the broader area of Honshu during the time interval of fifty years (1964 - 2013), and on correlation of seismological data with tectonic structure and surface morphology, including the sea floor. The aim of the thesis is not to predict the earthquake retroactively but to put its occurrence into the context of the long-term development of seismicity, to identity differences in the seismic response to the process of plate tectonics prior, during and after the Tohoku-Oki earthquake and to delimitate the tectonic causes of areal limitation of the extent of the aftershock series. The space-time analysis of the development of earthquake occurrence utilized relocated hypocentral parameters primarily identified by the International Seismological Centre (so called EHB data), focal mechanisms of the Global Centroid Moment Tensor Solution programme, surface morphology and bathymetry data, and eruptive history database of active volcanoes. A series of epicentral maps and vertical sections of focal zones were construced for the analysis of seismic...
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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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Subduction factory interaction of subduction-related magma with the overlying lithosperic wedge
Kuna, Václav ; Špičák, Aleš (advisor) ; Hrubcová, Pavla (referee)
III Abstract The world's largest earthquakes, the most destructive tsunamis and the most explosive vol- canism are generated at subduction zones at convergent plate margins. Despite of high societal and economic importance of these areas, there are still some poorly understood processes, such as the process of magma generation and ascent to the Earth surface. This thesis contributes to the solution of the problem of location of source areas of calc-alkaline magma and its migration. It consists of two parts: in the first one, the phenomenon of vol- canism at convergent plate margins and seismological background are described, while the second part explores structures in the lithosphere beneath volcanoes in the broader region of the Banda Arc (Indonesia). For the purposes of the research, the ISC hypocentral de- terminations based on data from the global seismic network, relocated by a procedure of Engdahl et al. and collected in the so called EHB database were used. The analyses of spa- tial, time and magnitude dependencies in the dataset of earthquakes occurring within the Banda Arc area enabled us to formulate several conclusions: The occurrences of strong teleseismically recorded earthquakes in the lithospheric wedge beneath volcanoes suggests that the respective rock medium is not partially melted....
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Contribution to the tectonic interpretation of the seismicity pattern of Banda Arc, SE Asia
Matějková, Radka ; Zahradník, Jiří (referee) ; Špičák, Aleš (advisor)
i Abstract Contribution to the tectonic interpretation of the seismicity pattern of the Banda Arc, Southeast Asia Tectonic structure of the Banda Arc in Southeast Asia is regarded as an extremely complicated unit as it is situated at the intersection of four lithospheric plates: Eurasian, Indo-Australian, Pacific, and Philippine. The present-day tectonic regime is arc-continent collision. The seismotectonic pattern of the Banda Arc region was studied using global seismological data. Relocated EHB hypocentral determinations for the period 1964 - 2004 and fault plane solutions of Harvard CMT data for the period 1976 - 2004 have been used. The analysis of spatial distribution of earthquake foci and the analysis of focal mechanisms enabled to distinguish the foci belonging to the Wadati-Benioff zone of the subducting plate from those occurring in the overriding plate. The analysis discriminated two opposite dipping subduction zones - southern Banda subduction and northern Seram subduction. The following specific phenomena were observed in the Wadati-Benioff zone: (i) unusual lateral bent of the Wadati-Benioff zone of the southern Banda subduction, (ii) intermediate- depth (100 - 220 km), vertically situated domain of the highest seismicity within the Wadati-Benioff zone of the southern Banda subduction, (iii)...
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SLICE Seismic lithospheric investigation of Central Europe
Akademie věd ČR, Geofyzikální ústav, Praha ; Uličný, David ; Růžek, Bohuslav ; Hubatka, František ; Špaček, Petr ; Švancara, Jan ; Brož, Milan ; Novotný, Miloslav ; Karousová, Olina ; Hrubcová, Pavla ; Špičák, Aleš ; Novotný, Miroslav
Projekt SLICE má za úkol zkoumat hlubinnou stavbu středoevropské oblasti a jeho cílem je přispět k výzkumu stavby zemské kůry a svrchního pláště v oblasti Českého masivu a jeho styku se sousedními tektonickými jednotkami. Pro studium hlubinné stavby je využívána seismická refrakční metoda, kdy se registrují seismické vlny generované uměle vyvolanými odpaly a posléze je zjišťována rychlost šíření seismických vln v různých hloubkách. Tyto údaje pak zprostředkovaně poskytnou informace o strukturních vlastnostech měřeného prostředí až do oblasti svrchního pláště. Je popsáno propojení refrakčních experimentů ALP 2002 a SUDETES 2003 na našem území.
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