Continuous in situ measurements of volcanic gases with a diode-laser-based spectrometer: CO2 and H2O concentration and soil degassing at Vulcano (Aeolian islands: Italy)
Authors: De Rosa M., Gagliardi G., Rocco A., Somma R., De Natale P., De Natale G.
Autors Affiliation: CNR, Istituto Nazionale di Ottica Applicata, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy;
INGV, Osservatorio Vesuviano, Via Diocleziano 328, 80124 Napoli, Italy
Abstract: We report on a continuous-measurement campaign carried out in Vulcano (Aeolian islands, Sicily), devoted to the simultaneous monitoring of CO2 and H2O concentrations. The measurements were performed with an absorption spectrometer based on a semiconductor laser source emitting around a 2-mu m wavelength. The emitted radiation was selectively absorbed by two molecular rovibrational transitions specific of the investigated species. Data for CO2 and H2O concentrations, and CO2 soil diffusive flux using an accumulation chamber configuration, were collected at several interesting sampling points on the island (Porto Levante beach-PLB, Fossa Grande Crater – FOG- and Valley of Palizzi, PAL). CO2/H2O values, measured on the ground, are very similar (around 0.019 (+/- 0.006)) and comparable to the previous discrete detected values of 0.213 (Fumarole F5-La Fossa crater rim) and 0.012 (Fumarole VFS – Baia Levante beach) obtaid during the 1977-1993 heating phase of the crater fumaroles.In this work much more homogeneous values are found in different points of the three sites investigated. The field work, although carried out in a limited time window (25th-28th August 2004), pointed out the new apparatus is suitable for continuous gas monitoring of the two species and their ratios, which are important geochemical indicators of volcanic activity, for which other reliable continuous monitoring systems are not yet available.
Journal/Review: GEOCHEMICAL TRANSACTIONS
Volume: 8 Pages from: 5-1 to: 5-11
KeyWords: carbon dioxide; concentration (composition); degassing; fumarole; in situ measurement; spectrometer; volcanic gas, Eurasia; Europe; Italy; Lipari Islands; Messina [Sicily]; Sicily; Southern Europe; VulcanoDOI: 10.1186/1467-4866-8-5Citations: 4data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2019-10-13References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here