Idioma:

Estimating rates of decompression from textures of erupted ash particles produced by 1999-2006 eruptions of Tungurahua Volcano, Ecuador

Wright, Heather M. N ; Cashman, Katharine V ; Mothes, Patricia A ; Hall, Minard L ; Ruiz, Andrés Gorki ; Le Pennec, Jean-Luc

Geology (Boulder), 2012-07, Vol.40 (7), p.619-622 [Periódico revisado por pares]

Boulder: Geological Society of America (GSA)

Texto completo disponível

Citações Citado por

Enviar para

Título:
Estimating rates of decompression from textures of erupted ash particles produced by 1999-2006 eruptions of Tungurahua Volcano, Ecuador
Autor: Wright, Heather M. N ; Cashman, Katharine V ; Mothes, Patricia A ; Hall, Minard L ; Ruiz, Andrés Gorki ; Le Pennec, Jean-Luc
Assuntos: Andes ; bubbles ; Correlation analysis ; Crystallization ; Crystals ; decompression ; degassing ; Earth Sciences ; Ecuador ; Environmental Sciences ; eruptions ; explosive eruptions ; Global Changes ; igneous and metamorphic rocks ; igneous rocks ; lava ; Magma ; magmas ; Measurement ; particulate materials ; Petrology ; pyroclastics ; Quaternary geology ; Sciences of the Universe ; South America ; stratovolcanoes ; strombolian-type eruptions ; textures ; Tungurahua ; volcanic ash ; volcanic rocks ; Volcanoes ; Volcanology
É parte de: Geology (Boulder), 2012-07, Vol.40 (7), p.619-622
Descrição: Persistent low- to moderate-level eruptive activity of andesitic volcanoes is difficult to monitor because small changes in magma supply rates may cause abrupt transitions in eruptive style. As direct measurement of magma supply is not possible, robust techniques for indirect measurements must be developed. Here we demonstrate that crystal textures of ash particles from 1999 to 2006 Vulcanian and Strombolian eruptions of Tungurahua volcano, Ecuador, provide quantitative information about the dynamics of magma ascent and eruption that is difficult to obtain from other monitoring approaches. We show that the crystallinity of erupted ash particles is controlled by the magma supply rate (MSR); ash erupted during periods of high magma supply is substantially less crystalline than during periods of low magma supply. This correlation is most easily explained by efficient degassing at very low pressures (<<50 MPa) and degassing-driven crystallization controlled by the time available prior to eruption. Our data also suggest that the observed transition from intermittent Vulcanian explosions at low MSR to more continuous periods of Strombolian eruptions and lava fountains at high MSR can be explained by the rise of bubbles through (Strombolian) or trapping of bubbles beneath (Vulcanian) vent-capping, variably viscous (and crystalline) magma.
Editor: Boulder: Geological Society of America (GSA)
Idioma: Inglês

Links

View record in HAL

Voltar para lista de resultados

Realização: Logos de Redes Sociais:

Estimating rates of decompression from textures of erupted ash particles produced by 1999-2006 eruptions of Tungurahua Volcano, Ecuador

Wright, Heather M. N ; Cashman, Katharine V ; Mothes, Patricia A ; Hall, Minard L ; Ruiz, Andrés Gorki ; Le Pennec, Jean-Luc

Boulder: Geological Society of America (GSA)

Buscando em bases de dados remotas. Favor aguardar.