0000000000229316
AUTHOR
Aiuppa A
Validation of a novel Multi-Gas sensor for volcanic HCl alongside H
Volcanic gas emission measurements inform predictions of hazard and atmospheric impacts. For these measurements, Multi-Gas sensors provide low-cost in situ monitoring of gas composition but to date have lacked the ability to detect halogens. Here, two Multi-Gas instruments characterized passive outgassing emissions from Mt. Etna’s (Italy) three summit craters, Voragine (VOR), North-east Crater (NEC) and Bocca Nuova (BN) on 2 October 2013. Signal processing (Sensor Response Model, SRM) approaches are used to analyse H2S/SO2 and HCl/SO2 ratios. A new ability to monitor volcanic HCl using miniature electrochemical sensors is here demonstrated. A “direct-exposure” Multi-Gas instrument contained…
Real-time detection of volcanic plume H2O, CO2 and SO2 as a precursor to 2006 Mt. Etna eruptions
Mount Etna, in southern Italy, is well known for its uninterrupted open-vent degassing activity from the summit craters, making the volcano the largest point source of volcanogenic volatiles on Earth. Notwithstanding a substantial improvement of our understanding of degassing rates and mechanisms over the past two decades, analytical limitations still hamper the quantitative evaluation of the total volatile budget from the volcano. In contrast with the routine sensing of volcanic SO2 by UV-spectroscopy (Allard, 1997; Caltabiano et al., 2004), only a few spot determinations of CO2 emissions from Mount Etna have been reported to date (Allard et al., 1991; Aiuppa et al., 2006), while H2O emiss…
Turmoil at Turrialba Volcano (Costa Rica): Degassing and eruptive processes inferred from high-frequency gas monitoring.
Abstract Eruptive activity at Turrialba Volcano (Costa Rica) has escalated significantly since 2014, causing airport and school closures in the capital city of San José. Whether or not new magma is involved in the current unrest seems probable but remains a matter of debate as ash deposits are dominated by hydrothermal material. Here we use high‐frequency gas monitoring to track the behavior of the volcano between 2014 and 2015 and to decipher magmatic versus hydrothermal contributions to the eruptions. Pulses of deeply derived CO2‐rich gas (CO2/Stotal > 4.5) precede explosive activity, providing a clear precursor to eruptive periods that occurs up to 2 weeks before eruptions, which are acc…
Conduit dynamics and post explosion degassing on Stromboli: A combined UV camera and numerical modeling treatment.
Abstract Recent gas flux measurements have shown that Strombolian explosions are often followed by periods of elevated flux, or “gas codas,” with durations of order a minute. Here we present UV camera data from 200 events recorded at Stromboli volcano to constrain the nature of these codas for the first time, providing estimates for combined explosion plus coda SO2 masses of ≈18–225 kg. Numerical simulations of gas slug ascent show that substantial proportions of the initial gas mass can be distributed into a train of “daughter bubbles” released from the base of the slug, which we suggest, generate the codas, on bursting at the surface. This process could also cause transitioning of slugs i…