Home > Search Results: keywords:"East-African orogeny"
Search:
Search Tips :: Advanced Search
Search collections:
Sort by: Display results: Output format:
National Repository of Grey Literature 2 records found  Search took 0.01 seconds. 
Tectonic and metamorphic evolution of the Tokar-Barka Terrain (East-African Orogeny)
 Hořenínová, Marie ; Verner, Kryštof (advisor) ; Peřestý, Vít (referee)
in English This bachelor's thesis summarizes the tectonic and metamorphic evolution of the Tokar-Barka Unit in the southern part of the Arabian-Nubian Shield. The compilation includes an information of regional division, lithological pattern, age, deformation structures and record of metamorphic evolution, mainly in the context of East African orogenic processes. The main episodes of geodynamic evolution are briefly discussed in a regional context. Key words: East-African Orogeny, Arabian-Nubian Shield, Tokar-Barka Unit, Deformation, Tectonics, Metamorphic evolution
Detailed record
Lithology, geochemistry and metamorphic evolution of northern Hammar Domain (East-African Orogeny)
 Gashe, Negessa Gonfa ; Verner, Kryštof (advisor) ; Racek, Martin (referee)
in English The studied part of the Hammar Domain is composed of the Neoproterozoic basement rocks belonging to the Southern Ethiopian Shield (SES), partly covered by volcanic and volcanosedimentary deposits of the Main Ethiopian Rift (MER). The high-grade migmatite to migmatized biotite paragneiss and amphibolites were intruded by numerous peraluminous granite and granodiorite bodies and gabbros of metaluminous composition. The results of U/Pb zircon dating of granodiorite yielded at 507.7 ± 3.2 Ma, which is interpreted as the age of magma emplacement and crystallization. The P-T estimation reveal the peak P-T conditions at ca. 1.21 to 0.88 GPa and ca. 842 to 700 řC which were followed by retrograde part P-T path (from ca. 0.84 to 0.12 GPa) with decrease of temperature from ca. 700 to 464 řC. The emplacement of gabbro in syn-tectonic settings took place at P = ca. 0.87 to 0.93 GPa and T ca. 650 řC reflecting magma emplacement to ca. 30 km in depth. Next, the syn- to post- tectonic emplacement and crystallization of biotite and amphibole-bioitite granodiorite reveal P = 0.27-0.52 GPa and T ca. 720-836. The events described above were associated with the latter period of the East-African Orogeny, which resulted in overall consolidation of the Gondwana continent.
Detailed record

Interested in being notified about new results for this query?
Subscribe to the RSS feed.
Digital Repository :: Search :: Submit :: Personalize :: Help
Powered by Invenio v1.1.2
Maintained by admin.invenio@techlib.cz
This site is also available in the following languages:
Česky  English