Volcanic debris avalanches - from collapse to hazards

<p>This year marks the 40<sup>th</sup> anniversary of the 1980 Mt. St. Helens eruption and sector collapse. In acknowledgement to the vast research dedicated to understanding volcano collapse and debris avalanche dynamics, we have collated in a book the topic’s current state of the art. Within 12 chapters, this book contains reviews of and new insights from the work done over the past four decades, and provides outlooks and recommendations for future research. It is part of the Springer Book Series ‘Advances in Volcanology’ and the chapters contributed by a team of experts cover the following topics:</p><ol><li>Introduction </li> <li>A historical perspective on lateral collapse and debris avalanches</li> <li>Terminology and strategy to describe volcanic landslides and debris avalanches </li> <li>Distribution and geometric parameters of volcanic debris avalanche deposits </li> <li>Destabilizing factors that promote volcano flank collapse</li> <li>Volcanic debris avalanche transport kinematics and emplacement mechanisms</li> <li>Sedimentology of volcanic debris avalanche deposits</li> <li>Climatic and paleo-climatic implications </li> <li>Computer simulation of volcanic debris avalanches</li> <li>Volcanic debris avalanche deposits in the context of volcaniclastic ringplain successions</li> <li>Cyclicity in edifice destruction and regrowth </li> <li>Volcanic island lateral collapses and submarine volcanic debris avalanche deposits</li> </ol><p>Finally, the aim of the book is to reach the professional research community as well as students and a broader audience interested in hazard management in volcanic environments.</p>

Volcano collapse along the Aleutian Ridge (western Aleutian Arc)

The Aleutian Ridge, in the western part of the Aleutian Arc, consists of a chain of volcanic islands perched atop the crest of a submarine ridge with most of the active Quaternary stratocones or caldera-like volcanoes being located on the northern margins of the Aleutian Islands. Integrated analysis of marine and terrestrial data resulted in the identification and characterization of 17 extensive submarine debris avalanche deposits from 11 volcanoes. Two morphological types of deposits are recognizable, elongate and lobate, with primary controls on the size and distribution of the volcanic debris being the volume and nature of material involved, proportion of fine grained material, depth of emplacement and the paleo-bathymetry. Volume calculations show the amount of material deposited in debris avalanches is as much as three times larger than the amount of material initially involved in the collapse, suggesting the incorporation of large amounts of submarine material during transport. The orientation of the collapse events is influenced by regional fault systems underling the volcanoes. The western Aleutian Arc has a significant tsunamigenic potential and communities within the Aleutian Islands and surrounding areas of the North Pacific as well as shipping and fishing fleets that cross the North Pacific may be at risk during future eruptions in this area.