2006/01/01 by Shanaka L. de Silva, G. Zandt, Robert B. Trumbull +3 · 191 citations
Earth and Planetary Sciences · #Geological and Geochemical Analysis #High-pressure geophysics and materials #earthquake and tectonic studies #Geology #Volcano #Tectonics #Seismology #Perspective (graphical) #Earth science
paper · doi:10.1144/gsl.sp.2006.269.01.04
published in Geological Society London Special Publications 269(1), 47-63 (Geological Society of London)
openalex publication_date 2006/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/25
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 km 3 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.