Landslide deposits offshore many volcanic islands provide evidence of catastrophic lateral collapses. These deposits span a larger volume range than their continental equivalents, and can generate devastating tsunamis. All historical volcanic-island lateral collapses have occurred in arc settings, and have been characterised by rapid failure and efficient tsunami generation. The varied morphology of their deposits is influenced both by lithological properties and the nature of the substrate. Many deposits show evidence of extensive seafloor erosion and transformation into debris flows, and the propagation of frontally-confined sediment deformation beyond and beneath the primary deposit. Mobilised volumes can far exceed that of the initial failure, and accurate deposit interpretation requires internal geophysical imaging and sampling. Around intraplate ocean-island volcanoes, multi-unit turbidites suggest that lateral collapses may occur in discrete stages; although this would reduce their overall tsunamigenic potential, the volumes of individual stages of collapse remain very large. Numerical models of both landslide and tsunami processes in ocean-island settings are difficult to test, and the smaller collapses that typify island arcs are an important focus of research due to their higher global frequency, availability of direct failure and tsunami observations, and a need to better understand the signals of incipient collapse to develop approaches for tsunami hazard mitigation.
|Title of host publication||Volcanic Debris Avalanches|
|Subtitle of host publication||From Collapse to Hazard|
|Editors||Matteo Roverato, Anja Dufresne, Jonathan Procter|
|Number of pages||25|
|ISBN (Print)||9783030574109, 9783030574130|
|Publication status||Published - 17 Nov 2020|
|Name||Advances in Volcanology|
Bibliographical noteFunding Information:
Acknowledgements We thank Matteo Roverato for editorial handling of this manuscript and the other editors for organisation of this volume. SW acknowledges funding from the Natural Environment Research Council (NE/I02044X/1 and 2 and NET002026/1). We are grateful to Simon Day for detailed comments on a draft of this manuscript, and to Neil Mitchell and Rui Quartau for constructive reviews.
© 2021, Springer Nature Switzerland AG.
- Debris avalanche
- Flank collapse
- Flow transformation
- Submarine landslide
- Tsunami hazard
- Volcanic island
ASJC Scopus subject areas
- Geochemistry and Petrology