Mechanisms of Ash Generation at Basaltic Volcanoes: The Case of Mount Etna, Italy

AbstractMany of the standard volcanic gas flux measurement approaches involve absorption spectroscopy in combination with wind speed measurements. Here, we present a new method using video images of volcanic plumes to measure the speed of convective structures combined with classical plume theory to estimate volcanic fluxes. We apply the method to a nearly vertical gas plume at Villarrica Volcano, Chile, and a wind-blown gas plume at Mount Etna, Italy. Our estimates of the gas fluxes are consistent in magnitude with previous reported fluxes obtained by spectroscopy and electrochemical sensors for these volcanoes. Compared to conventional gas flux measurement techniques focusing on SO2, our new model also has the potential to be used for sulfur-poor plumes in hydrothermal systems because it estimates the H2O flux.

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Days to weeks of syn-eruptive magma interaction: High-resolution geochemistry of the 2002-03 branched eruption at Mount Etna

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2021.116904 ◽

2021 ◽

Vol 565 ◽

pp. 116904

Author(s):

Ruadhán Magee ◽

Teresa Ubide ◽

John Caulfield

Keyword(s):

High Resolution ◽

Mount Etna

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First experimental evidence for the CO<sub>2</sub>-driven origin of Stromboli's major explosions

Solid Earth Discussions ◽

10.5194/sed-3-411-2011 ◽

2011 ◽

Vol 3 (1) ◽

pp. 411-430 ◽

Cited By ~ 2

Author(s):

A. Aiuppa ◽

M. Burton ◽

P. Allard ◽

T. Caltabiano ◽

G. Giudice ◽

...

Keyword(s):

Experimental Evidence ◽

Co2 Emission ◽

Weight Ratio ◽

Co2 Flux ◽

Recent Model ◽

Stromboli Volcano ◽

Plumbing System ◽

Gas Leakage ◽

Basaltic Volcanoes ◽

Monitoring Strategies

Abstract. We report on the first detection of CO2 flux precursors of the till now unforecastable larger than normal ("major") explosions that intermittently occur at Stromboli volcano (Italy). Automated survey of the crater plume emissions in the period 2006–2010, during which 12 such explosions happened, demonstrate that these events are systematically preceded by a brief phase of increasing CO2/SO2 weight ratio (up to >40) and CO2 flux (>1300 t/d) with respect to the time-averaged values of 3.7 and ~500 t/d typical for standard Stromboli's activity. These signals are best explained by the accumulation of CO2-rich gas at a discontinuity of the plumbing system (decreasing CO2 emission at the surface), followed by increasing gas leakage prior to the explosion. Our observations thus support the recent model of Allard (2010) for a CO2-rich gas trigger of recurrent major explosions at Stromboli, and demonstrate the possibility to forecast these events in advance from geochemical precursors. These observations and conclusions have clear implications for monitoring strategies at other open-vent basaltic volcanoes worldwide.

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Lava Channel Formation during the 2001 Eruption on Mount Etna: Evidence for Mechanical Erosion

Physical Review Letters ◽

10.1103/physrevlett.96.028501 ◽

2006 ◽

Vol 96 (2) ◽

Cited By ~ 17

Author(s):

Carmelo Ferlito ◽

Jens Siewert

Keyword(s):

Mount Etna ◽

Channel Formation ◽

Lava Channel ◽

Mechanical Erosion ◽

2001 Eruption

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Chemical variation of clinopyroxene phenocrysts from the trachybasaltic lavas of Mount Etna, Sicily

Mineralogical Magazine ◽

10.1180/minmag.1980.043.330.10 ◽

1980 ◽

Vol 43 (330) ◽

pp. 765-770 ◽

Cited By ~ 11

Author(s):

A. M. Duncan ◽

R. M. F. Preston

Keyword(s):

Trace Element ◽

Mount Etna ◽

Chemical Variation ◽

Etna Volcano ◽

Trace Element Chemistry ◽

Sector Zoning ◽

Steady Decrease ◽

Element Chemistry

SummaryThe chemical variation of clinopyroxene phenocrysts from the trachybasaltic lavas of Etna volcano is described. The phenocrysts show a limited, but distinct trend in chemical variation from calcic-augite in the hawaiites to augite in the benmoreites. The trend of this variation is unusual, being one of Mg-enrichment with differentiation of the magma. Ca shows a steady decrease in the clinopyroxenes from the hawaiites to the benmoreites. Na, however, shows little chemical variation in the pyroxenes. The trace element chemistry is briefly examined. The clinopyroxenes show well-developed oscillatory and sector zoning. The basal {11} sectors are enriched in Si and Mg and depleted in Ti, Al, and Fe relative to the {100}, {110}, and {010} prism sectors.

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