Multi-Proxy Characterisation of the Storegga Tsunami and Its Impact on the Early Holocene Landscapes of the Southern North Sea

Vincent Gaffney ,Benjamin Gearey ,Tim Kinnaird ,C M Batt ,Matthew Law ,Sarah J Davies ,John E Whittaker ,Simon Fitch ,Logan Kistler ,Kevin Kearney ,Tom Hill ,C Richard Bates ,Richard Telford ,Merle Muru ,Becky Cribdon ,Roselyn Ware ,Sam Harris ,Mohammed Ben Sharada ,Janice R Walker ,Rosie Everett ,Ben Stern ,Alexander J Finlay ,Martin Bates ,Derek Hamilton ,Robin G Allaby

doi:10.3390/geosciences10070270

Abstract

Doggerland was a landmass occupying an area currently covered by the North Sea until marine inundation took place during the mid-Holocene, ultimately separating the British landmass from the rest of Europe. The Storegga Event, which triggered a tsunami reflected in sediment deposits in the northern North Sea, northeast coastlines of the British Isles and across the North Atlantic, was a major event during this transgressive phase. The spatial extent of the Storegga tsunami however remains unconfirmed as, to date, no direct evidence for the event has been recovered from the southern North Sea. We present evidence of a tsunami deposit in the southern North Sea at the head of a palaeo-river system that has been identified using seismic survey. The evidence, based on lithostratigraphy, geochemical signatures, macro and microfossils and sedimentary ancient DNA (sedaDNA), supported by optical stimulated luminescence (OSL) and radiocarbon dating, suggests that these deposits were a result of the tsunami. Seismic identification of this stratum and analysis of adjacent cores showed diminished traces of the tsunami which was largely removed by subsequent erosional processes. Our results confirm previous modelling of the impact of the tsunami within this area of the southern North Sea, and also indicate that these effects were temporary, localized, and mitigated by the dense woodland and topography of the area. We conclude that clear physical remnants of the wave in these areas are likely to be restricted to now buried, palaeo-inland basins and incised river valley systems.

Highlights

The Holocene pre-inundation landscape of the southern North Sea, known as Doggerland, was TheHolocene pre-inundation landscape of the southernNorthhunter-gathererSea, known as Doggerland, was[1].a gently undulating, low-relief area associated withMesolithic communities a gently undulating, low-relief area associated withMesolithic hunter-gatherer communities [1].SeaSea-level rise during the mid-Holocene period at the regional scale was episodic due to local variations rise rebound, during theautocompaction mid-Holocene period at the regional scale was episodic local variations in level isostatic of sediments and palaeotidal range. dueThe to precise timing and in isostatic of their sediments range
The core most strongly associated with the seismic signal, ELF001A was analysed with the following techniques; grain size measurement using standard dry sieving, loss on ignition, palaeomagnetic, geochemical scanning, organic chemistry profiling for lipid analysis, optically stimulated luminescence (OSL) profiling and dating, radiocarbon (RC) dating, foraminifera and ostracod assessment, pollen analysis, diatom analysis, mollusca analysis and sedimentary ancient DNA
Our evidence shows that the Storegga tsunami impacted coastlines in the area of the southern

Summary

Introduction

The Holocene pre-inundation landscape of the southern North Sea, known as Doggerland, was TheHolocene pre-inundation landscape of the southernNorthhunter-gathererSea, known as Doggerland, was[1].a gently undulating, low-relief area associated withMesolithic communities a gently undulating, low-relief area associated withMesolithic hunter-gatherer communities [1].SeaSea-level rise during the mid-Holocene period at the regional scale was episodic due to local variations rise rebound, during theautocompaction mid-Holocene period at the regional scale was episodic local variations in level isostatic of sediments and palaeotidal range. dueThe to precise timing and in isostatic of their sediments range. The Holocene pre-inundation landscape of the southern North Sea, known as Doggerland, was The. Holocene pre-inundation landscape of the southern. Known as Doggerland, was[1]. A gently undulating, low-relief area associated with. Mesolithic communities a gently undulating, low-relief area associated with. Mesolithic hunter-gatherer communities [1]. SeaSea-level rise during the mid-Holocene period at the regional scale was episodic due to local variations rise rebound, during theautocompaction mid-Holocene period at the regional scale was episodic local variations in level isostatic of sediments and palaeotidal range. The to precise timing and in isostatic of their sediments range. The precise timing and[2]. Extent of such rebound, processesautocompaction and impactand on palaeotidal

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