Barrovian and Buchan type metamorphism in the Pan-African Kaoko belt, Namibia: implications for its geotectonic position within the framework of Western Gondwana

Research Article| September 01, 2004 Barrovian and Buchan type metamorphism in the Pan-African Kaoko belt, Namibia: implications for its geotectonic position within the framework of Western Gondwana T.M. Will; T.M. Will Institut für Mineralogie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, e-mail: thomas.will@mail.uni-wuerzburg.de; okrusch@mail.uni-wuerzburg.de Search for other works by this author on: GSW Google Scholar M. Okrusch; M. Okrusch Institut für Mineralogie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, e-mail: thomas.will@mail.uni-wuerzburg.de; okrusch@mail.uni-wuerzburg.de Search for other works by this author on: GSW Google Scholar B.B. Gruner B.B. Gruner Institut für Mineralogie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Present address: Lehrstuhl für Allgemeine, Angewandte und Ingenieur-Geologie, Technische Universität München, Arcisstrasse 21, D-80290 München, Germany, Birgit.Gruner@helmholz.de Search for other works by this author on: GSW Google Scholar South African Journal of Geology (2004) 107 (3): 431–454. https://doi.org/10.2113/107.3.431 Article history first online: 07 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation T.M. Will, M. Okrusch, B.B. Gruner; Barrovian and Buchan type metamorphism in the Pan-African Kaoko belt, Namibia: implications for its geotectonic position within the framework of Western Gondwana. South African Journal of Geology 2004;; 107 (3): 431–454. doi: https://doi.org/10.2113/107.3.431 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietySouth African Journal of Geology Search Advanced Search Abstract The polyphase deformed Pan-African Kaoko belt, Namibia, which is part of the late Neoproterozoic mobile belt system of western Gondwana, consists of pre-Pan-African basement gneisses, Pan-African volcano-sedimentary cover sequences and large granitoid intrusions.The eastern part of the Kaoko belt comprises a nearly complete Barrovian sequence of medium to high temperature/medium pressure metapelitic rocks, which range in grade from greenschist- to upper amphibolite-facies conditions. From east to west, north-northwest to northwest trending subparallel garnet-, staurolite-, kyanite-, and kyanite-sillimanite-muscovite metamorphic zones can be distinguished, whereas the western Kaoko belt is dominated by a high temperature/low pressure Buchan-type metamorphism with sillimanite-K-feldspar- and garnet-cordierite-sillimanite-K-feldspar metamorphic zones. The two metamorphic terranes are tectonically separated by the Puros shear zone.The pressure-temperature path for each metamorphic zone was inferred by using observed mineral assemblages and reaction textures, a combination of various geothermobarometers and, in particular, pseudosections. Peak metamorphic conditions of the Barrovian and Buchan zones indicate peak pressure-temperature ratios of ~20°C/km and 50°C/km, respectively. The Barrovian-type terrane is probably linked to a fold-and-thrust belt, the Buchan-type terrane may be linked to a magmatic arc setting. Similarities between the Kaoko belt in northwest Namibia and the central Ribeira belt in South America might point to a common geological history. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.