Title
Large ignimbrite eruptions and volcano-tectonic depressions in the Central Andes: A thermomechanical perspective
Date Issued
22 December 2006
Access level
metadata only access
Resource Type
journal article
Author(s)
De Silva S.
Zandt G.
Trumbull R.
Viramonte J.G.
Jiménez N.
Publisher(s)
Geological Society of London
Abstract
The Neogene ignimbrite flare-up of the Altiplano Puna Volcanic Complex (APVC) of the Central Andes produced one of the best-preserved large silicic volcanic fields on Earth. At least 15 000 km3 of magma erupted as regional-scale ignimbrites between 10 and 1 Ma, from large complex calderas that are typical volcano-tectonic depressions (VTD). Simple Valles-type calderas are absent. Integration of field, geochronological, petrological, geochemical and geophysical data from the APVC within the geodynamic context of the Central Andes suggests a scenario where elevated mantle power input, subsequent crustal melting and assimilation, and development of a crustal-scale intrusive complex lead to the development of APVC. These processes lead to thermal softening of the sub-APVC crust and eventual mechanical failure of the roofs above batholith-scale magma chambers to trigger the massive eruptions. The APVC ignimbrite flare-up and the resulting VTDs are thus the result of the time-integrated impact of intrusion on the mechanical strength of the crust, and should be considered tectonomagmatic phenomena, rather than purely volcanic features. This model requires a change in paradigm about how the largest explosive eruptions may operate. © The Geological Society of London.
Start page
47
End page
63
Volume
269
Language
English
OCDE Knowledge area
Geografía física Vulcanología
Scopus EID
2-s2.0-33845580244
ISBN
1862392110 9781862392113
Source
Geological Society Special Publication
ISSN of the container
03058719
Sources of information: Directorio de Producción Científica Scopus