Hazard potential of volcanic flank collapses raised by new megatsunami evidence

Ramalho, Ricardo S., Winckler, Gisela, Madeira, José, Helffrich, George R., Hipólito, Ana, Quartau, Rui, Adena, Katherine and Schaefer, Joerg M. 2015. Hazard potential of volcanic flank collapses raised by new megatsunami evidence. Science Advances 1 (9) , e1500456. 10.1126/sciadv.1500456

PDF - Published Version Available under License Creative Commons Attribution. Download (8MB)

Abstract

Large-scale gravitational flank collapses of steep volcanic islands are hypothetically capable of triggering megatsu- namis with highly catastrophic effects. Yet, evidence for the generation and impact of collapse-triggered megatsu- namis and their high run-ups remains scarce or is highly controversial. Therefore, doubts remain on whether island flank failures truly generate enough volume flux to trigger giant tsunamis, leading to diverging opinions concerning the real hazard potential of such collapses. We show that one of the most prominent oceanic volcanoes on Earth— Fogo, in the Cape Verde Islands—catastrophically collapsed and triggered a megatsunami with devastating effects ~73,000 years ago. Our deductions are based on the recent discovery and cosmogenic 3He dating of tsunamigenic deposits found on nearby Santiago Island, which attest to the impact of this giant tsunami and document wave run-up heights exceeding 270 m. The evidence reported here implies that Fogo’s flank failure involved at least one fast and voluminous event that led to a giant tsunami, in contrast to what has been suggested before. Our observations therefore further demonstrate that flank collapses may indeed catastrophically happen and are capable of trigger- ing tsunamis of enormous height and energy, adding to their hazard potential.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Earth and Environmental Sciences
Publisher:	American Association for the Advancement of Science
ISSN:	2375-2548
Date of First Compliant Deposit:	28 June 2021
Date of Acceptance:	7 July 2015
Last Modified:	23 May 2023 16:01
URI:	https://orca.cardiff.ac.uk/id/eprint/142093

Citation Data

Cited 69 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item