Four multicyclic complex calderas and smaller ignimbrite shields located within the Altiplano Puna Volcanic Complex of the Central Andes (APVC) erupted 13000 km³ of magma within the last 11 Ma. One of the largest and most complex of these is the Cerro Guacha Caldera. Ar-Ar age determinations and paleomagnetic directions...
Four multicyclic complex calderas and smaller ignimbrite shields located within the Altiplano Puna Volcanic Complex of the Central Andes (APVC) erupted 13000 km³ of magma within the last 11 Ma. One of the largest and most complex of these is the Cerro Guacha Caldera. Ar-Ar age determinations and paleomagnetic directions...
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degree of Master of Science in Geology Presented on May 22, 2012
Title: The Cerro Guacha Caldera
The Toba Caldera Complex is the youngest resurgent caldera in the last 100 kyrs, formed from four overlapping eruptions starting 1.2 Myrs ago. The last caldera-forming eruption, the Youngest Toba Tuff eruption, occurred ~74 kyrs ago, emitting 2800 km3 of ash and pumice into the atmosphere and forming the caldera...
From detailed fieldwork and biotite ⁴⁰Ar/³⁹Ar dating correlated with paleomagnetic analyses of lithic clasts, we present a revision of the stratigraphy, areal extent and volume estimates of ignimbrites in the Cerro Galan volcanic complex. We find evidence for nine distinct outflow ignimbrites, including two newly identified ignimbrites in the Toconquis...
Highlights: New data reveal for the first time a history of the last ∼33.7 ky of uplift of Samosir. Minimum uplift rates were high (4.9 cm/year) for the first 11.2 ky but diminished after that to <1 cm/year for the last 22.5 ky. Numerical modeling suggests that rebound of remnant...
Highlights: New data reveal for the first time a history of the last ∼33.7 ky of uplift of Samosir. Minimum uplift rates were high (4.9 cm/year) for the first 11.2 ky but diminished after that to <1 cm/year for the last 22.5 ky. Numerical modeling suggests that rebound of remnant...
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Balige
Location Names
10 km
Dimensions of Toba Caldera: 30km x 100km
Map outlines from Google Maps
Highlights: New data reveal for the first time a history of the last ∼33.7 ky of uplift of Samosir. Minimum uplift rates were high (4.9 cm/year) for the first 11.2 ky but diminished after that to <1 cm/year for the last 22.5 ky. Numerical modeling suggests that rebound of remnant...
Full Text:
reveal details of the post-caldera history at the Earth’s youngest resurgent
supervolcano, Toba caldera
Highlights: New data reveal for the first time a history of the last ∼33.7 ky of uplift of Samosir. Minimum uplift rates were high (4.9 cm/year) for the first 11.2 ky but diminished after that to <1 cm/year for the last 22.5 ky. Numerical modeling suggests that rebound of remnant...