National Repository of Grey Literature 5 records found  Search took 0.01 seconds. 
Scoria cones on the Moon: morphologies, distribution, and mechanism of their formation
Novotný, Radek ; Brož, Petr (advisor) ; Tomek, Filip (referee)
The recent observations of the Moon show, that there was long-lasting volcanic activity on the lunar surface, that left many volcanic features behind. These features are in the form of lunar seas, which are covering thousands of kilometers wide impact basins, or small volcanic bodies of various shapes. Some of these bodies are relatively small, up to 170 meters high conical bodies occurring on the near side and far side of the Moon. Based on research about the Marius Hills and South Pole-Aitken locations, it was suggested, that these bodies could be a lunar equivalent of terrestrial cinder cones. Cinder cones are created by degassing and fragmentation of magma with subsequent deposition of pyroclastic material into the surroundings. This shape similarity of the lunar cones to the terrestrial cones is surprising, as there is less gravitational acceleration on the Moon's surface and the atmosphere is missing. This means, that particles are able to flow further, and this should also affect the appearance of the volcanic bodies. The aim of this work is to review available literature mentioning lunar cones, to map their frequencies on the surface of the Moon, to determine their basic shapes and explain possible differences or concordances in their shapes with terrestrial cinder cones. On the basis of the...
Record of mechanical processes during emplacement of shallow-level postcaldera intrusions: an example from Cínovec granite, Bohemian Massif
Vitouš, Petr ; Tomek, Filip (advisor) ; Trubač, Jakub (referee)
Collapse calderas are volcanic depressions created by emptying of underlying magma chamber during volcanic eruption and following fall of upper layers. After this the event is often succeeded by resurgence and magma chamber is filled with new magma, which may lead to creation of dike complexes and laccoliths. Inner structure of these resurgent magmatic bodies is defined by many processes like injection of magma, flow and deformation by local and regional stress fields. During crystallization, magma is still vulnerable to deformation, crystals may react to these deformations and orient themselves to it, and the inner structure may become overprinted. So, the creation of magmatic structures happens during final stages of emplacement and records only the last increment of deformation of magma. For studying the existence of inner structures even from macroscopically isotropic rocks, which may show the characteristics of mechanisms of creation of these rocks, I chose the anisotropy of magnetic susceptibility technique (AMS). This work is focused on the Cínovec granite in the Altenberg- Teplice caldera, Krušné hory mountains on the border between Czechia and Germany. Apart from the studied Cínovec granite this caldera is penetrated by series of other granitic bodies. The result of my study is for interpretation...
Magnetic fabric, magma flow and tectonic deformation in volcano-plutonic systems
Tomek, Filip ; Žák, Jiří (advisor) ; Lexa, Jaroslav (referee) ; Petronis, Michael (referee)
Magnetic fabric, magma flow and tectonic deformation in volcano-plutonic systems ABSTRACT This Ph.D. thesis aims to investigate dynamics of emplacement and tectonic history of selected volcano-plutonic complexes in a continental magmatic arc and back arc setting. The thesis presents new data sets from five field areas, presented in separate chapters, which could be viewed as representing a vertical sections through upper part of an intermediate to felsic magmatic system. From top to bottom in this ‛imaginary' vertical system, the examined units are: (1) andesitic lava domes and (2) sub-volcanic magma chambers (<3 km deep) of the Miocene Štiavnica volcano- plutonic complex, Western Carpathians (Slovakia), (3) Shellenbarger pluton (<3 km depth) within the mid-Cretaceous Minarets caldera, Sierra Nevada batholith in California (USA), and ~7-10 km deep granitoids of (4) Lower-Cretaceous Wallowa batholith, Blue Mountains province in Oregon (USA) and (5) Late Devonian Staré Sedlo complex, central Bohemian Massif (Czech Republic). The research incorporates extensive field and structural data, supported by analysis of igneous textures and anisotropy of magnetic susceptibility (AMS). The latter is further accompanied by detailed examination of magnetic mineralogy using thermomagnetic measurements and optical and back...
The Late Devonian to early Carboniferous kinematic evolution of the Teplá-Barrandian/Moldanubian boundary
Tomek, Filip ; Žák, Jiří (advisor) ; Babuška, Vladislav (referee)
ENGLISH ABSTRACT The Late Devonian to Early Carboniferous kinematic evolution of the Teplá-Barrandian/Moldanubian boundary The Staré Sedlo complex (SSC) is a relic of meta-igneous arc-related pluton in the southern part of the Sedlčany-Krásná Hora roof pendant, intruded by granitoids of the Central Bohemian Plutonic Complex along the boundary of Teplá-Barrandian (TBU) and Moldanubian units (MU), Bohemian Massif. The SSC mainly comprises deformed orthogneisses of calc-alkaline granodiorite to tonalite protoliths of Late Devonian age (380−365 Ma; Košler et al., 1993) that were commonly mingled with minor basic magmas. Locally preserved subhorizontal intrusive contacts of the orthogneisses against their meta-sedimentary host rock indicate that these magmas intruded as a sill complex. The SSC preserves a rather unusual flat-lying subsolidus foliation (dip <40ř) associated with subhorizontal ~NE-SW-trending mineral lineation. Mesoscopic structures, anisotropy of magnetic susceptibility (AMS), and deformational microstructures indicate prolate shape of the strain ellipsoid with dominant coaxial pure shear regime. The solid state microstructures record cooling of the orthogneiss protolith down to the ambient greenschist facies conditions followed by its static recrystallization due to the intrusion of the younger...

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