The University of Southampton
University of Southampton Institutional Repository

The timing and frequency of large-volume submarine landslides and turbidity currents along the north-eastern Atlantic Margin

The timing and frequency of large-volume submarine landslides and turbidity currents along the north-eastern Atlantic Margin
The timing and frequency of large-volume submarine landslides and turbidity currents along the north-eastern Atlantic Margin
Submarine landslides and turbidity currents are one of the most voluminous sediment transport mechanisms operating on our planet. Due to their potential size (>100 km3) and speed (>20 m/s) they pose considerable risk to coastal settlements and strategic marine infrastructure. This thesis aims to investigate the processes that precondition and trigger submarine landslides and turbidity currents within submarine canyons and on open continental slopes. Sediment cores, age models, and statistical analyses are used initially to test the effects of eustatic sea level on the recurrence rates of turbidity currents that fill and flush the Nazaré Canyon. Recurrence rates of turbidity currents that fill the canyon are strongly influenced by eustatic sea level, while more infrequent flows that flush the canyon are only associated with shifts in eustatic sea level periodicity and amplitude. The form of the frequency distribution of canyon filling and flushing turbidity currents also differ markedly, suggesting they have different triggers.This thesis also aims to understand the geohazard implications of large submarine landslides. The Trænadjupet Slide is a large (>400 km3) submarine landslide that occurred approximately 4,000 years ago on the Norwegian Margin. Unlike some other large submarine landslides, the Trænadjupet Slide did not trigger a widespread tsunami based on available coastal studies. The age of the Trænadjupet Slide is refined here to between ~2,600 and ~3,400 cal BP. The absence of a widespread tsunami associated with the Trænadjupet Slide may be explained by its emplacement dynamics (e.g. speed, acceleration, or time gaps between stages of failure). These findings have importance for landslide geohazards in the North Atlantic, as they suggest that other similarly-sized slides on the Norwegian Margin or elsewhere may not have produced very damaging tsunamis.
University of Southampton
Allin, Joshua Reg
360b2637-6755-44fd-87ff-0e1eb4759c22
Allin, Joshua Reg
360b2637-6755-44fd-87ff-0e1eb4759c22
Talling, Peter
1cbac5ec-a9f8-4868-94fe-6203f30b47cf

Allin, Joshua Reg (2016) The timing and frequency of large-volume submarine landslides and turbidity currents along the north-eastern Atlantic Margin. University of Southampton, Doctoral Thesis, 221pp.

Record type: Thesis (Doctoral)

Abstract

Submarine landslides and turbidity currents are one of the most voluminous sediment transport mechanisms operating on our planet. Due to their potential size (>100 km3) and speed (>20 m/s) they pose considerable risk to coastal settlements and strategic marine infrastructure. This thesis aims to investigate the processes that precondition and trigger submarine landslides and turbidity currents within submarine canyons and on open continental slopes. Sediment cores, age models, and statistical analyses are used initially to test the effects of eustatic sea level on the recurrence rates of turbidity currents that fill and flush the Nazaré Canyon. Recurrence rates of turbidity currents that fill the canyon are strongly influenced by eustatic sea level, while more infrequent flows that flush the canyon are only associated with shifts in eustatic sea level periodicity and amplitude. The form of the frequency distribution of canyon filling and flushing turbidity currents also differ markedly, suggesting they have different triggers.This thesis also aims to understand the geohazard implications of large submarine landslides. The Trænadjupet Slide is a large (>400 km3) submarine landslide that occurred approximately 4,000 years ago on the Norwegian Margin. Unlike some other large submarine landslides, the Trænadjupet Slide did not trigger a widespread tsunami based on available coastal studies. The age of the Trænadjupet Slide is refined here to between ~2,600 and ~3,400 cal BP. The absence of a widespread tsunami associated with the Trænadjupet Slide may be explained by its emplacement dynamics (e.g. speed, acceleration, or time gaps between stages of failure). These findings have importance for landslide geohazards in the North Atlantic, as they suggest that other similarly-sized slides on the Norwegian Margin or elsewhere may not have produced very damaging tsunamis.

Text
Allin, J_Thesis revised
Available under License University of Southampton Thesis Licence.
Download (9MB)

More information

Published date: October 2016
Organisations: Ocean and Earth Science, University of Southampton, Geology & Geophysics

Identifiers

Local EPrints ID: 407493
URI: https://eprints.soton.ac.uk/id/eprint/407493
PURE UUID: 6397d027-8104-4783-a9ea-679bc93853e0
ORCID for Joshua Reg Allin: ORCID iD orcid.org/0000-0002-4003-7495

Catalogue record

Date deposited: 13 Apr 2017 01:02
Last modified: 13 Mar 2019 20:03

Export record

Contributors

Author: Joshua Reg Allin ORCID iD
Thesis advisor: Peter Talling

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×