Volcano instability: a review of contemporary themes

Abstract

Active volcanoes are revealed to be dynamically evolving structures, the growth and development of which are characteristically punctuated by episodes of instability and subsequent structural failure. Edifice instability typically occurs in response to one or more of a range of agencies, including magma emplacement, the overloading or oversteepening of slopes, and peripheral erosion. Similarly, structural failure of a destabilized volcano may occur in response to a number of triggers of which seismogenic (e.g tectonic or volcanic earthquakes) or magmagenic (e.g. pore-pressure changes due to magma intrusion) are common. Edifice failure and consequent debris avalanche formation appears to occur, on average, at least four times a century, and similar behaviour is now known to have occurred at volcanoes on Mars and Venus. Realization of the potential scale of structural failures and associated eruptive activity has major implications for the development of monitoring and hazard mitigation strategies at susceptible volcanoes, which must now address the possibility of future collapse events which may be ten times greater than that which occurred at Mount St Helens in 1980.

Sector collapses and large landslides on Late Pleistocene–Holocene volcanoes in Kamchatka, Russia

“…In Kamchatka, preHolocene collapse(s) on Shiveluch are matched in scale only by Late Pleistocene collapses of Avachinsky volcano (see below). Worldwide most reported subaerial collapses of similar volumes also occurred in Late Pleistocene (Siebert, 1996;Siebert et al, 2004), while Holocene collapses tend to be under 10 km 3 (McGuire, 1996). Note: Holocene debris avalanche deposits, their numbers and ages according to Ponomareva et al (1998) with minor later corrections.…”

Neogene-Quaternary Volcanic forms in the Carpathian-Pannonian Region: a review

“…Volcano instability has been recently recognized as a significant catastrophic landform modification process [243][244][245]. Current research has recognized that nearly every volcanic setting shows results of volcano failure and their associated large volume volcanic debris avalanche deposits and typical hummocky terrains [246][247][248][249][250][251].…”

“…Erosion remnants of scoria cones are commonly strongly modified after erosion [94,290], and their original volcanic landform can only hardly be recognized [95,97,291]. In spite of the general assumption of the fast erosion of scoria cones, there are remarkable well-preserved scoria cones 245 Brought to you by | MIT Libraries Authenticated Download Date | 5/9/18 10:40 PM known from the central part of the BBHVF [58,114]. These scoria cone remnants are about 3-2.3 Ma old and still retain their original crater morphology and some part of their constructional edifice [114].…”

La dorsal NE de Tenerife: hacia un modelo del origen y evolución de los rifts de islas oceánicas

“…Los factores desencadenantes de los colapsos en islas oceánicas se agrupan en internos, asociados principalmente a la fuerza ascensional del magma (Siebert, 1984;Carracedo, 1994;Carracedo et al, 1998;McGuire, 1996;Elsworth & Day, 1999), y externos, relacionados en última instancia con agentes climáticos (McMurtry et al, 2004;Quidelleur et al, 2008). Obviamente hay una amplia casuística y se puede dar una combinación de factores desencadenantes.…”