A review on onshore tsunami deposits along the Atlantic coasts

• Published in: Earth-Science Reviews
• Main Authors: Costa, Pedro J. M., Dawson, Sue, Ramalho, Ricardo S., Engel, Max, Dourado, Francisco, Bosnic, Ivana, Andrade, César
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Elsevier 2021
• Subjects: Arctic; Storegga
• Online Access: https://orca.cardiff.ac.uk/id/eprint/142091/; https://doi.org/10.1016/j.earscirev.2020.103441

This paper reviews the evidence for onshore sedimentary imprints of tsunami inundation known from the geological record of the Atlantic basin. The central aim of the paper is to offer a broad overview on the main deposits and key localities that have been documented along the Atlantic coastlines, and which attest to the local or regional impact of tsunamis during historical, pre-historical and recent geological times. Considerable detail is devoted to summarising key diagnostic criteria used to identify the deposits as tsunami-derived, and to set each deposit in its own unique geomorphological setting and context, always referring to the latest scientific knowledge of the events that generated them. The paper also discusses the relationships between the different tsunamigenic sources that concurred to the formation of the deposits, as well as critical information on magnitude and frequency, as inferred from the sedimentary responses preserved in the sediment archives. Documented case studies range from the well-studied landslide-triggered and earthquake-triggered Storegga and 1755 Lisbon tsunamis, respectively, to collapse- and eruption-triggered tsunamis in the Atlantic archipelagos, to other less well-known events in the south Atlantic, Caribbean and Arctic. Despite its less frequent tsunami recurrence, the Atlantic coastal stratigraphy presents some world-class case studies and outstanding outcrops, from which critical knowledge can be gained with respect to some of the most enigmatic aspects of tsunami science.