--> Abstract: Geological Structure and History of Western Russian Arctic (Barents-Kara region), by Nikolay Malyshev; #90177 (2013)

Datapages, Inc.Print this page

Geological Structure and History of Western Russian Arctic (Barents-Kara region)

Nikolay Malyshev

There are four large sedimentary basins in the Barents-Kara region: Timan-Pechora (in Pechora Sea), East-Barents (including South-Barents and North-Barents depocentres), North-Kara and South-Kara. Timan-Pechora basin has Timanian (Neoproterozoic to Cambrian) basement. Ordovician and Devonian rift phases took place. The basin was a foreland basin during Mid-Late Permian and Mid-Late Triassic times for Uralides. A number of inversion and detachment-related structures are typical for this basin. The East-Barents basin has Caledonian, Timanian and older basement. The basin subsidence started due to Late Devonian to Early Carboniferous rifting. Postrift subsidence took place since middle Carboniferous times. Rapid mid-Permian to Triassic sedimentation was connected with origin of mountain systems in Urals-West Siberia and Taymyr regions. Inversion tectonics took place during Mesozoic and Cenozoic times. North-Kara basin has Neoproterozoic (Timanian) basement (including older possible terranes). The basin was originated due to Early Ordovician rifting. Mid-Ordovician to Lower Devonian deposits compile postrift megasequence. Carbonates are possibly dominated. Evaporates are presented in Mid-Late Ordovician. Salt-related tectonics is recognized for Urvantsev Basin in north-eastern part of North-Kara Basin. Mid-Late Devonian is presented by possibly distal Caledonian molasses. Main compression and inversion events took place close to Devonian/Carboniferous transition. Carboniferous to Mesozoic deposits cover the entire basin with angular unconformity at bottom. South-Kara basin has Late Paleozoic (Uralian) and older basement. The basin was originated during Late Permian to Early Triassic rifting. Mid-Triassic to Eocene deposits compile postrift cover. Transpression inversion events took place during mid-Triassic, Jurassic/Cretaceous transition and Cenozoic times. Vize-Ushakov Ridge separates East-Barents and North-Kara basins. This ridge has a pre-Late Devonian folded basement. This ridge was originated due to possible Caledonian folding. North-Siberian Swell separates South-Kara and North-Kara basins. It has pre-Triassic basement. The Ordovician rifting within Timan-Pechora and North-Kara basins took place in a back-arc subduction-related environment. The Late Devonian rifting within East-Barents basin is an enigma till now. We propose a back-arc rifting also in a connection with volcanic arc along Novaya Zemlya.

AAPG Search and Discovery Article #90177©3P Arctic, Polar Petroleum Potential Conference & Exhibition, Stavanger, Norway, October 15-18, 2013