Granitoid intrusions at the periphery of Kursk block as a part of Paleoproterozoic silica large igneous province at the Eastern Sarmatia
Year: 2024
Type: article
Abstract: At the eastern border of the Archean Kursk block of Sarmatia the Paleoprotorozoic 2.04–2.08 Ga diorite-granodiorite magmatism is widespread. The intrusive massifs granitoids are metaluminous calc-silica I-type rocks enriched with incoherent elements (LILE and LREE) with negative Ti, P and Nb anomalies. They have wide variety of εNd(T) values in rocks and εHf(T) values in zircons, and vary greatly in melt origin depths with the heterogenous Archean lower crust mafic sources. The diorites have the less radiogenic ancient crustal sources. Granodiorites have Paleo- and Mesoarchean and more juvenile Neoarchean sources. The reason of intensive 2.06 Ga magmatism was the astenospheric mantle uplift during the breakdown of pushed oceanic plate due to flat subduction. The plate breakdown and the mafic underplating lead to intracrustal melting in the upper plate consisting of different age Archean and Paleoproterozoic crustal fragments which were joint as a result of previous accretion. Diorite-granodiorite magmas were formed at melting points of different depths in the ancient Archean crust at the periphery of Kursk block with involvement of the Eastern Sarmarian orogen Paleoproterozoic lithosphere fragments into the melting sources.
Source: Петрология
Authors: К. А. Savko, А. V. Samsonov, Е. Kh. Korish, А. N. Larionov, Е. B. Salnikova, А. А. Ivanova, N. S. Bazikov, S. V. Tsybulyaev, М. V. Chervyakovskaya
Institutions: Russian Academy of Sciences, Institute of Geology of Ore Deposits Petrography Mineralogy and Geochemistry, Voronezh State University, A.P. Karpinsky Russian Geological Research Institute, Institute of Precambrian Geology and Geochronology, Ural Branch of the Russian Academy of Sciences, Zavaritsky Institute of Geology and Geochemistry
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W4405246552