Sequential plug formation, disintegration by Vulcanian explosions, and the generation of granular Pyroclastic Density Currents at Tungurahua volcano (2013–2014), Ecuador

Abstract:

Following 84 years of repose, Tungurahua volcano, Ecuador initiated its present eruptive episode in October 1999, but its PDC activity only began in July 2006. A period of highly energetic Vulcanian eruptions started in 2012, those of 14 July 2013, 18 October 2013, and 1 February 2014 being the most important. These eruptions were well-monitored by a 5-station broadband seismic and acoustic array. Repeated repose intervals of ~ 3.5 months between Vulcanian events (VEI ~ 2) suggest that gases in the ascending juvenile magma experienced sequential pressurization cycles, as magma of preceding eruptive events solidified to form plugs that sealed the conduit. Every 34 months plug failure occurred, abrupt decompression followed, and the resulting Vulcanian explosions are associated with the highest seismic and acoustic energies ever registered anywhere. Small to moderate-sized PDC flows associated …

Año de publicación:

2015

Keywords:

Fuente:

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