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| Titel |
Gas emissions and slug dynamics at Stromboli |
| VerfasserIn |
Tom D. Pering, Andrew J. S. McGonigle, Mike R. James, Giancarlo Tamburello, Alessandro Aiuppa |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250129278
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| Publikation (Nr.) |
 EGU/EGU2016-9366.pdf |
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| Zusammenfassung |
| We present UV camera data for 200 strombolian and hornito degassing events at Stromboli
during June and July 2014. This data was processed to calculate SO2 masses for each event.
In addition to calculating SO2 masses of the slugs which generate these events we also
observe periods of elevated flux following events, termed the gas coda, lasting ≈ 30 –
180 s, which we also calculate SO2masses for. This provided a range of explosive
plus coda SO2 masses of ≈ 18 – 225 kg. In combination with 3D fluid numerical
simulations of slug flow we begin to probe a possible generation mechanism for the
observed gas codas. The simulations show that ‘daughter bubbles’ are produced from
the base of ascending slugs, which result in gas mass loss rates from the slugs of
between ≈ 1.2 – 14.2 kg s−1. Nf, the dimensionless inverse viscosity number,
can be used to characterise the form of a slug wake, and hence when mass loss
through daughter bubble production may occur. However, the observed daughter
bubble behaviour occurs at lower levels of Nf than predicted by previous mm-
to cm-scale studies and suggests that extra physics (e.g. surface tension), beyond
that included in Nf, may be needed to parameterise daughter bubble production.
We suggest that daughter bubbles could play a role in modulating explosivity of
strombolian eruptions as a potential causal mechanism for gas coda production. |
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