Journal Article10.1007/S00445-017-1105-0
Volcanic gas composition changes during the gradual decrease of the gigantic degassing activity of Miyakejima volcano, Japan, 2000-2015
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TL;DR: The composition of volcanic gases discharged from Miyakejima volcano has been monitored during intensive degassing activity that began after the eruption in 2000 and quickly decreased to 5kt/day by 2003.
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Abstract: The composition of volcanic gases discharged from Miyakejima volcano has been monitored during the intensive degassing activity that began after the eruption in 2000. During the 15 years from 2000 to 2015, Miyakejima volcano discharged 25.5 Mt of SO2, which required degassing of 3 km3 of basaltic magma. The SO2 emission rate peaked at 50 kt/day at the end of 2000 and quickly decreased to 5 kt/day by 2003. During the early degassing period, the volcanic gas composition was constant with the CO2/SO2 = 0.8 (mol ratio), H2O/SO2 = 35, HCl/SO2 = 0.08, and SO2/H2S = 15. The SO2 emission rate decreased gradually to 0.5 kt/day by 2012, and the gas composition also changed gradually to CO2/SO2 = 1.5, H2O/SO2 = 150, HCl/SO2 = 0.15, and SO2/H2S = 6. The compositional changes are not likely caused by changes in degassing pressure or volatile heterogeneity of a magma chamber but are likely attributed to an increase of hydrothermal scrubbing caused by large decrease of the volcanic gas emission rate, suggesting a supply of gases with constant composition during the 15 years. The intensive degassing was modeled based on degassing of a convecting magma conduit. The gradual SO2 emission rate that decrease without changes in volcanic gas composition is attributed to a reduction of diameter of the convecting magma conduit.
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References
Redox processes governing the chemistry of fumarolic gas discharges from White Island, New Zealand
TL;DR: In this article, a systematic thermodynamic evaluation of some 250 gas analyses for 100 to 800°C fumaroles on White Island, New Zealand, was carried out, and the gas discharges were found to be made up of two source components: (1) a primary "magmatic" component high in SO2, rising rapidly and directly from the underlying magma; and (2) a secondary "hydrothermal" component rising slowly from a two-phase, saline brine-vapor envelope surrounding the magmatic system.
675
Magmatic gas scrubbing: implications for volcano monitoring
TL;DR: In this paper, the authors model thermochemically the reaction of magmatic gases with water to better understand scrubbing and its implications for volcano monitoring, and suggest that CO2 is the main species to monitor when scrubbing exists; another candidate is H2S(g), but it can be affected by reactions with aqueous ferrous iron.
385
Multi-decadal satellite measurements of global volcanic degassing
TL;DR: In this article, the authors examined the temporal and latitudinal distribution of volcanic SO 2 emissions and reassess the relationship between eruptive SO 2 discharge and eruption magnitude, finding a first-order correlation between SO 2 emission and volcanic explosivity index (VEI), but with significant scatter.
362
Sulphur output and magma degassing budget of Stromboli volcano
TL;DR: In this article, air-borne measurements of the plume flux of Stromboli volcano during 1980-93 show that the volcano emits very large amounts of gas, mostly by open-conduit degassing between explosive outbursts, while exuding little basalt.
353
Excess degassing from volcanoes and its role on eruptive and intrusive activity
TL;DR: In this paper, three mechanisms are proposed to explain various degassing modes, including eruption of bubble-accumulated magma, degassing of a convecting magma column, and permeable gas transportation from a deep magma chamber.
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