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The major tectonic units of the Neoarchean Volgo-Uralia continent, which is ~600,000 km2 in area, are contrastingly expressed in regional gravity and magnetic maps. Interpretations of seismic images of the crust along the TATSEIS geotraverse in combination with 3D density and magnetic crust models provide insights into the volumetric representation of tectonic structures of various ranks. Granulite-gneiss crust of Volgo-Uralia is characterized by elevated thickness (~60 km and locally up to 65–70 km). The deep structure of Volgo-Uralia assumes that the entire crustal section, including the lower crust, is composed of high-density granulite metamorphic facies rocks. Specific structural units called ovoids play the main role in the structure of this continent. The ovoids are bowl-shaped crustal blocks, round or oval in plan view, 300–600 km across, and with the base reaching a level of crust-mantle interface at ~60 km. Ovoids are bounded by conic surfaces of reverse (thrust)-faults, along which their outer parts are thrust over the framework. The Tokmov, Buzuluk, Verkhnekamsk, Krasnoufimsk, and Orenburg ovoids, which generally are not in contact with one another, are dominated by mafic granulites, gabbroic rocks, gabbroanorthosites, and ultramafic rocks. A significant contribution of deep-seated intrusive rocks suggests that metamorphism developed in the lower and middle crust at high PT parameters that exceed the maximum estimates (940–950 °C, 9.5 kbar) recorded in samples of borehole cores. The interovoidal space is occupied by elongated oval synforms up to 200–400 km long. This space is considered to be an interovoidal domain, which includes three relatively narrow, compressed synforms (Yelabuga-Bondyug, Kilmez, Chusovaya) and four oval synforms (Srednevyatka, Verkhnevyatka, North-Tatar, Almetevsk). The Tokmov ovoid is framed in the southeast by the Tuma and Penza belts. Synforms are filled with metasedimentary granulites and mafic metaigneous rocks. The protoliths were formed over the time interval from 3.4–3.2 to 3.1–3.0 Ga. The internal zoning of the Volgo-Uralia crust is related to numerous local centers within ovoids and interovoidal region. At least two high-temperature metamorphic events were followed by periods of retrogression: 2.74–2.70 and 2.62–2.59 Ga. The areal and especially high-temperature character of tectonothermal processes during formation of the Neoarchean crust of the Volgo-Uralia Craton, and distinct geometrization of space with recognition of several concentric domains, finds a universal explanation in ascent of multiple plumes.

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