THE PROCESSES OF CATACLASIS, MYLONITIZATION AND POST-TECTONIC MINERALIZATION (BLASTESIS) RELATED TO THE OVERTHRUSTING OF THE MACERA NAPPE (THE GREATER CAUCASUS)

David Shengelia

doi:10.52340/pajig.2024.136.01

Authors

David Shengelia Tbilisi State University https://orcid.org/0000-0003-3598-0734

DOI:

https://doi.org/10.52340/pajig.2024.136.01

Keywords:

the Greater Caucasus, Macera nappe, cataclase, mylonitization and blastesis processes

Abstract

The article deals with the geological processes revealed during the overthrusting of the Macera nappe from the Pass sub-zone on the infrastructure of the Elbrus sub-zone of the Greater Caucasus structural zone. It is shown that in the contact zone of the Macera nappe and infrastructure, there is a significant difference in the degree of their regional metamorphism; the intensively developed cataclase, mylonitization and blastesis processes associated with shearing are characterized; it is shown that the energy of the thermal effect of friction is insignificant in autochthonous rocks, while it is higher in allochthonous rocks. Significant recrystallization of minerals in the autochthon is observed only in its direct contact with the allochthon.

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Author Biography

David Shengelia, Tbilisi State University

Doctor of geological-mineralogical sciences, Head of the Department of Petrology, Mineralogy, Geochemistry and Lithology of Alexandre Janelidze Institute of Geology of Ivane Javakhishvili Tbilisi State University, Chief Scientist.

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