Skip to Main Content
GEOREF RECORD

Forecasting catastrophic stratovolcano collapse; a model based on Mount Taranaki, New Zealand

Anke V. Zernack, Shane J. Cronin, Mark S. Bebbington, Richard C. Price, Ian E. M. Smith, Robert B. Stewart and Jonathan N. Procter
Forecasting catastrophic stratovolcano collapse; a model based on Mount Taranaki, New Zealand
Geology (Boulder) (September 2012) 40 (11): 983-986

Abstract

Regular large-scale edifice collapse and regrowth is a common pattern during the long lifespans of andesitic stratovolcanoes worldwide. The >130 k.y. history of Mount Taranaki, New Zealand, is punctuated by at least 14 catastrophic collapses, producing debris avalanche deposits of 1 to >7.5 km (super 3) . The largest of these sudden events removed as much as one-third of the present-day equivalent cone. The resulting deposits show similar sedimentary and geomorphic features, suggesting similar proto-edifice characteristics, failure trigger mechanisms, and runout path conditions. Each collapse was followed by sustained renewed volcanism and cone regrowth, although there are no matching stepwise geochemical changes in the magma erupted; instead a stable, slowly evolving magmatic system has prevailed. Last Glacial climatic variations are also uncorrelated with the timing or magnitudes of edifice collapse. We demonstrate here that, if the magmatic composition erupted from stratovolcanoes is constant and basement geology conditions are stable, large-scale edifice collapse and the generation of catastrophic debris avalanches will be governed by the magma supply rate. Using a mass balance approach, a volume-frequency model can be applied to forecasting both the probable timing and volume of future edifice failure of such stratovolcanoes. In the Mount Taranaki case, the maximum potential size of a present collapse is estimated to be 7.9 km (super 3) , while the maximum interval before the next collapse is <16.2 k.y. The current annual collapse probability is approximately 0.00018, with the most likely collapse being a small one (<2 km (super 3) ).


ISSN: 0091-7613
EISSN: 1943-2682
Coden: GLGYBA
Serial Title: Geology (Boulder)
Serial Volume: 40
Serial Issue: 11
Title: Forecasting catastrophic stratovolcano collapse; a model based on Mount Taranaki, New Zealand
Affiliation: Massey University, Institute of Natural Resources, Palmerston North, New Zealand
Pages: 983-986
Published: 20120904
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
References: 24
Accession Number: 2012-086323
Categories: Environmental geology
Document Type: Serial
Bibliographic Level: Analytic
Annotation: Accessed on September 13, 2012
Illustration Description: illus. incl. geol. sketch map
Source Medium: WWW
S39°17'60" - S39°17'60", E174°04'00" - E174°04'00"
Secondary Affiliation: University of Waikato, NZL, New ZealandUniversity of Auckland, NZL, New Zealand
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data from GeoScienceWorld, Alexandria, VA, United States. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States
Update Code: 201245
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal