Catastrophic glacial multi-phase mass movements: a special type of glacial hazard

• Main Authors: Petrakov, D. A., Chernomorets, S. S., Evans, S. G., Tutubalina, O. V.
• Other Authors: Faculty of Geography, University Centre for Engineering Geodynamics and Monitoring, Department of Earth and Environmental Sciences Waterloo, University of Waterloo Waterloo
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Canada; glacier*
• Online Access: https://hal.science/hal-00297100; https://hal.science/hal-00297100/document; https://hal.science/hal-00297100/file/adgeo-14-211-2008.pdf

International audience Many glacier-related hazards are well typified and studied, but some events stand out from conventional classifications. The Kolka-Karmadon catastrophic event on 20 September 2002 in North Ossetia, North Caucasus, Russia is used as an example of a complex glacier failure exhibiting characteristics such as high mobility, long runout, ultrarapid movement and multiphase behaviour. We consider terminology protocol for glacier hazard classification and then, using the Kolka-Karmadon event and several other examples from around the world, we propose a new term for this family of events. Catastrophic glacier multi-phase mass movement (CGMM) is described and further illustrated by eight major events from Russia, Georgia, Peru, Chile, and Canada. CGMM have a combination of specific features: extraordinary velocities and long-distance runout despite low path angle; progressive fluidisation along travel path; superelevation and run-up of the moving mass, air blast wave in the avalanche flow phase; entrainment of available materials in its path, and the repeated nature of the event. CGMM events may affect areas remote from glaciers which were previously considered as safe.