Skip to Main Content
Skip Nav Destination

The Bryansk-Kursk-Voronezh intracontinental collisional orogen was formed by the juvenile Middle Paleoproterozoic assemblages in combination with Early Paleoproterozoic complexes and areas of reworked Archean crust. The crucial events fall in the time interval 2.1–2.0 Ga. The orogen includes a sequence of second-order, near-meridional orogens, which, in turn, consist of tectonic belts. From the west eastward, these are the Krivoi Rog–Bryansk orogen, the orogen of the Kursk magnetic anomaly (KMA), and the East Voronezh orogen. The latter may be regarded as an axial (central) structural element, which marks a transient rupture of the continental crust. The north to south extent of the orogen along the strike of the second-order orogens reaches 900 km long and ca. 900 km in width. The Krivoi Rog–Bryansk orogen consists of two groups of tectonic belts. Its western region is composed of tectonic nappes pertaining to the Kulazhino gneiss and the Bryansk granulite-gneiss belts. The eastern region, including the Krupetsk-Znamensk belt and the Meshchevsk system of tectonic sheets, with significant role of intensely deformed banded iron formations (BIF) of the Kursk and Oskol groups, is also the western imbricated margin of the Archean Kursk craton. The volcanic-sedimentary BIF belts play the main role in the structure of the KMA orogen. The second important component is composed of subvolcanic and plutonic mafic-ultramafic, felsic, and alkaline rock complexes. Granite-gneiss domes are related to the final stage of the orogen evolution. The East Voronezh orogen consists of the Lipetsk-Losevka volcanic-plutonic belt and the Vorontsovka imbricated thrust belt, separated by the Losevka-Mamon suture. The evolution of the Bryansk-Kursk-Voronezh orogen as a whole includes: onset of rifting within the Archean Kursk craton (2.59–2.53 Ga); terrigenous and chemical sedimentation including BIF and volcanic activity (2.5–2.10 Ga), periodically accompanied by emplacement of intrusions (2.6–2.5 Ga and 2.1–2.05 Ga); metamorphism under granulite-facies conditions in the Kulazhino and Bryansk belts at 2.13 Ga and in the Vorontsovka belt at 2.10 Ga; intrusive magmatism in the Vorontsovka belt generally synchronous with high-temperature metamorphism; suprasubduction magmatism and formation of the Lipetsk-Losevka volcanic-plutonic belt 2.10–2.05 Ga ago; the collision-related reverse and thrust faulting and folding in the BIF belts accompanied by westward and south-westward overturning; rheomorphism and formation of granite-gneiss and granite-migmatite domes deforming the fold-nappe assemblages in the BIF belts of KMA; and the tectonothermal activity of postcollisional and anorogenic stages (2.07–1.9 Ga) expressed by emplacement of alkaline ultramafic and gabbro-syenite intrusions in the Lipetsk-Losevka belt and its hinterland. The most active phase of tectonic evolution spanned the time interval 2.1–2.0 Ga, which was no less than 100 Ma long and coincided with the active stage of extension, sedimentation, and high-temperature metamorphism in the northern part of the East European craton.

You do not currently have access to this chapter.

Figures & Tables




Citing Books via

Related Articles
Related Book Content
Close Modal

or Create an Account

Close Modal
Close Modal