Stratigraphy and geological events at the Frasnian-Famennian boundary in the Southern Urals

Abstract

Detailed biostratigraphic correlation of late Frasnian and Famennian sections in the Southern Urals shows that the key global scale events near the boundary of Frasnian and Famennian are clearly expressed in combination with important regional scale tectonic events. The maximum regression occured during triangularis zones time, being recorded as common hiatuses. The beginning of specific ultra-potassic mantle volcanism took place during the linguiformis Zone. Processes of olistostrome deposition, uplift of the Uraltau zone, the start of flysch deposition, and exhumation of the high pressure-low temperature Maksiutovo metamorphic complex also took place very close to the Frasnian-Famennian boundary, as the general regression coincided with active local tectonic movements as the Magnitogorsk island arc collised with the East European continent. The global scale events at the F-F boundary are connected with activity of the Late Devonian superplume, which encompassed a vast area of the Kazakhstanian, East European, Siberian, Gondwana and South Chinese plates.