Climatically controlled sedimentary processes on continental shelves

Abstract

Continental shelves with their large-scale depositional and erosional sedimentary structures are governed by shelf physiography, hydrodynamic regime, sediment flux, and climate-driven eustatic changes. The main aim is to investigate paleo-environmental organizations recorded in elongated depressions and confined depocenters in SE North Sea and NW Barents Sea, both of which were affected by the Eurasian Ice-Sheet during late Weichselian. Analysis of sediment echo-sounder and multichannel seismic data along with the sedimentological sampling enabled the identification of morphology and infill of Elbe Paleovalley (EPV), and external and internal geometry of Kveithola Drift (KD) in detail. Braided style paleodrainage was established at the base of EPV in periglacial environment. With Late Pleistocene-Early Holocene sea level rise, successive depocenters within EPV reflect the evolving hydrodynamic regime in tide- and wave-dominated environment until present. Moving towards high-latitudes, morphological and internal characteristics of KD suggest a bottom current flowing inside the trough. The formation of KD by Brine-enriched shelf water during winter season indicates the presence of coastal polynyas and increased storminess.