Repositorio
Institucional

Tassara, Andres

Basualto, Daniel

Lazo-Gil, Jonathan

Franco-Marin, Luis

Cardona, Carlos

San Martin, Juan

Gil-Cruz, Fernando

Calabi-Floddy, Marcela

Farias, Cristian

Anatomy of a high-silica eruption as observed by a local seismic network: the June 2011 Puyehue-Cordon Caulle event (southern Andes, Chile)

COPERNICUS GESELLSCHAFT MBH

SOLID EARTH

en

High-silica explosive eruptions are one of the most dangerous natural phenomena, yet it is unclear which processes are involved in this infrequent kind of event. We present the first systematic characterization of near-field seismicity associated with a large high-silica eruption analyzing data recorded before, during and after the 4 June 2011 rhyolitic eruption of Puyehue-Cordon Caulle Volcanic Complex (PCCVC). Results of a first-level data processing, developed by the Southern Andean Volcano Observatory (OVDAS) to monitor unrest and the evolution of the eruption, are complemented here with the relocation of hypocenters into a local 1D velocity model, the time series of the b value and the computation of the focal mechanism. This information allows us to define several phases before and after the onset of the eruption, describing details of the space-time evolution of seismicity, defining and characterizing the seismic sources, and identifying the structural control of the magmatic intrusion and stress variations during the eruption. Our results illuminate several underlying processes, with emphasis on the possible role that basement structures had on the storage, transport and evacuation of magma. Integrating our results with previous findings based on satellite geodesy and petrology of erupted materials, we discuss general conceptual models regarding destabilization of structurally controlled acidic magmatic systems, the pass from unrest to eruption, and changes in eruptive style and waning phases of eruptions, with broader implications for monitoring and forecast of violent silicic eruptions.

2023

artículo original

10.5194/se-14-69-2023

PDF

Puyehue–Cordón Caulle Volcanic Complex

Southern Andean Volcano Observatory

volcanoes - monitoring - Chile

Geoquímica y Geofísica

Complejo Volcánico Puyehue-Cordón Caulle

Observatorio de Volcanes Andinos del Sur

volcanes - monitoreo - Chile

69.0

87

artículo original

versión publicada

CC BY 4.0

CC BY 4.0

acceso abierto

acceso abierto

WOS:000921405400001

1869-9510

verde# dorado

Geoquímica y Geofísica

ANID 3200387

ANID 1151175

ANID 19I10397

ANID NCN19_167