Abrupt Climatic Changes As Triggering Mechanisms of Massive Volcanic Collapses
Journal of Volcanology and Geothermal Research 155 (2006) 329–333 www.elsevier.com/locate/jvolgeores Short communication Abrupt climatic changes as triggering mechanisms of massive volcanic collapses Lucia Capra Instituto de Geografía, UNAM, CU Coyoacan, 04510, Mexico DF, Mexico Received 7 March 2006; received in revised form 31 March 2006; accepted 19 April 2006 Available online 5 June 2006 Abstract Abrupt climate change can trigger volcanic collapses, phenomena that cause the destruction of the entire sector of a volcano, including its summit. During the past 30 ka, major volcanic collapses occurred just after main glacial peaks that ended with rapid deglaciation. Glacial debuttressing, load discharge and fluid circulation coupled with the post-glacial increase of humidity and heavy rains can activate the failure of unstable edifices. Furthermore, significant global warming can be responsible for the collapse of ice-capped unstable volcanoes, an unpredictable hazard that in few minutes can bury inhabited areas. © 2006 Published by Elsevier B.V. Keywords: volcanic collapse; global warming 1. Introduction Wyk de Vries et al., 2001; Clavero et al., 2002). Several analogue experiments have been performed to demon- Although climate changes have been considered to be strate how faults can deform volcanoes that finally a triggering mechanism for large eruptions (Rampino et collapse (Van Wyk de Vries and Borgia, 1996; Lagmay et al., 1979; McGuire et al., 1997), they have not, so far, al., 2000; Acocella, 2005; Norini and Lagmay, 2005). been related to the collapse of volcanoes. Unstable This is probably a very common mechanism, but it is volcanoes, whatever the origin of their instability, can spatially localized and can occur in an indeterminate collapse from the same triggering mechanism (McGuire, period of time.
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