Two Contrasting Fabric Patterns of Olivine Observed in Garnet and Spinel Peridotite from a Mantle-derived Ultramafic Mass Enclosed in Felsic Granulite, the Moldanubian Zone, Czech Republic

0337938 - GLÚ 2010 RIV GB eng J - Journal Article
Kamei, A. - Obata, M. - Michibayashi, K. - Hirajima, T. - Svojtka, Martin
Two Contrasting Fabric Patterns of Olivine Observed in Garnet and Spinel Peridotite from a Mantle-derived Ultramafic Mass Enclosed in Felsic Granulite, the Moldanubian Zone, Czech Republic.
Journal of Petrology. Roč. 51, 1/2 (2010), s. 101-123. ISSN 0022-3530. E-ISSN 1460-2415
Institutional research plan: CEZ:AV0Z30130516
Keywords : garnet peridotite * spinel peridotite * olivine fabrics * Bohemian Massif
Subject RIV: DB - Geology ; Mineralogy
Impact factor: 3.842, year: 2010

The Mohelno peridotite is a medium-sized ultramafic body (2 km x 4 km in size) enclosed in the Gfoehl granulites in the eastern part of the Bohemian Massif. To decipher the origin and history of this mantle-derived peridotite, we determined the mineral chemistry by electron microprobe analysis and olivine fabric patterns by the electron backscattered diffraction method for each rock type.We found two distinct types of olivine fabric (crystal-preferred orientation; CPO) in the peridotite, which can be correlated with the mineralogy and thermal history of each. Starting from a high-temperature (>1200°C) spinel peridotite, during exhumation and cooling in contact with surrounding granulites, the marginal part of the body was transformed to garnet peridotite, whereas the interior remained in the spinel-peridotite facies because cooling was slower inside the body.
Permanent Link: http://hdl.handle.net/11104/0181823