Plastically deformed dunites of the Tarlashkinskiy massif

The subject of inquiry is plastically deformed dunites of theTarlashkinskiy mountain mass located on the South-East of the Republic of Tuva. The research focused on the analysis of dunites petrostructural characteristics. As a result, several petrostructural types were taken into consideration: protogranular, porphyritic clastic, porphyritic lathic and mosaic. These types reproduce the sequence of rock plastic deformations. Quantitative assessment of deformation was carried out through the proportion of porphyritic clastic and recrystallized olivine grains, as well as regarding the extent of its specific surface and orientation degree. Two types of crystals were specified by size due to the X-ray research of dunites. The larger ones correspond to porphyritic clastic grains, and the smaller one to recrystallized grains. Thus the optical microscopy and X-ray analysis data agree with each other; this reflects the syntectonic recrystallization, in the process of which initial grains are being eliminated and the function of neogenic granules increases. Dunites originate in the result of total recrystallization, formed like a mosaic compact-grained olivine set, in which the sizes of grains and crystals became minimal.

Keywords

Authors

References