Recrystallization Features in Olivine from Dunites of the Tarlashkinsk Ultramafic Massif: New Data from the EBSD Analysis of Rock-Forming Grains

Abstract:

In this article, we analyzed connection between development of grain misorientation of different olivine fabrics from dunites of the Tarlashkinsk Massif (SE Tuva, Central Sibiria) and their geometrical parameters (grain size, specific area of grain boundaries, volume fraction of large and small components). Crystallographic orientation of olivine fabric types was also analyzed. It was indicated that bimodality in grain sizes disappears while changing into mosaic type. It was obtained by the EBSD method that the grain orientation changes starting with porphyroclastic type, and maximum scattering of olivine grain misorientations is observed when forming mosaic fabric. The results obtained confirm a hypothesis stipulated by authors earlier about deformation transformations of olivine as a result of geological processes during the obduction of mantle ultrabasites.

• Periodical: Advanced Materials Research (Volume 1085)
• Pages: 319-323
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1085.319
• Online since: February 2015
• Authors: Aleksey S. Kulkov*, Aleksey I. Chernishov, Dmitry V. Lychagin, Platon A. Tishin
• Keywords: EBSD, Grain Size, Olivine, Plastic Deformation

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