THE PEROVSK-KORNILOVKA SWELL: A PREVIOUSLY UNKNOWN LARGE STRUCTURAL UNIT OF THE ORENBURG CISURAL REGION

Abstract

Analysis and reinterpretation of several regional seismic profiles carried out by the Orenburg Geophysical Expedition in the Orenburg Cisural region allowed us to suggest the existence of an uplift (swell) in the central part of the present-day Ural Foredeep. This suggestion is consistent with an idea stated by Korolyuk. We mapped the Riphean–Vendian uplift, which is traced by the Riphean–Vendian deep reflectors and called the Perovsk–Kornilovka Swell, along three near-latitudinal profiles. The northern profile, profile 28 of the seismic group (s/g) 10/03, extends east of the Orenburg Swell across Well 108 and wells 70, 71, and 73 at the eastern wall of the foredeep to the frontal folds of the Urals. The second (Mednogorsk) profile (Novouspenovka s/g 10/79-80) extends 20 km south and parallel to profile 28 and reaches the town of Mednogorsk. The third profile, profile 26 (s/g 10/04), extends 20 km south of the Mednogorsk profile. The fourth near-longitudinal profile, profile 27, crosses the near-latitudinal profiles and extends to wells at the eastern wall of the foredeep.