0000000000003812
AUTHOR
Paonita A
Evidence of a recent input of magmatic gases into the quiescent volcanic edifice of Panarea, aeolian Islands, Italy
New insights into magma dynamics during last two eruptions of Mount Etna as inferred by geochemical monitoring from 2002 to 2005
Two distinct eruptive events characterize the volcanic activity at Mount Etna during the 2002 to 2005 period. We identified signals of magma ascent preceding these eruptions by geochemical monitoring of both chemical composition and He-isotope ratio of gas emissions from five locations in the peripheral area of the volcano. The geochemical signals are interpreted using the models proposed by Caracausi et al. (2003a, 2003b) and allow identification of episodes of magma ascent and estimation of the pressures of degassing magma. As observed for the 2001 eruption (Caracausi et al., 2003b), magma ascent probably triggered the onset of the 2002–2003 eruption, and minor events of magma ascent were…
Plume chemistry provides insights into the mechanisms of sulfur and halogen degassing at basaltic volcanoes,
This paper deals with sulfur, chlorine and fluorine abundances in the eruptive volcanic plume of the huge October 2002-January 2003 eruption of Mount Etna, aiming at relating the relevant compositional variations observed throughout with changes in eruption dynamics and degassing mechanisms. The recurrent sampling of plume acidic volatiles by filter-pack methodology revealed that, during the study period, S/Cl and Cl/F ratios ranged from 0.1-6.8 and 0.9-5.6, respectively. Plume S/Cl ratios increased by a factor of ∼10 as volcanic activity drifted from paroxysmal lava fountaining (mid- and late November) to passive degassing and minor effusion (early January), and then decreased to the low v…
Groundwater residence time estimations based on heat and 4He abundance: an application to Western Sicily (Italy) hydrothermal systems.
Mount Etna: dynamics of magma degassing and ascent towards the shallow levels of the feeding system
Sulphur behaviour in Etnean magmatic system (Italy
Sulfur is an essential volatile component of basaltic magmas and it is mostly dissolved as S6+ and/or S2- depending on the redox conditions. Mt. Etna continuously discharges enormous quantity of SO2 (~3563 t/d [1]). However these high flows are not fully understood in terms of S origin (magmatic or crustal) and of its behavior during magmatic evolution (fractional crystallization, magma mixing, vapor/melt fractionation [2]). Our research combines the study of sulfur in natural olivine hosted melt inclusions with an experimental study on S solubility in hydrous alkali basalts at magmatic conditions. We report new data of S in melt inclusions, belonging to six of the most characteristic Etnea…
Evidence of Two-Component Iblean-Like Mantle From 2001-2006 Igneous Products of Mount Etna
Geochemical monitoring of some peripheral gas emissions at Mount Etna: insights on its plumbing system
Noble Gases Investigation on Etnean Volcanic Gases and on the Erupted Products During the 2001-2006 Period
Data acquired during the last 20 years of geochemical monitoring of volcanic gases lead us to better understand how volcanoes work. According to theoretical and experimental investigations, both the chemical and isotopic changes in sampled volcanic gases have been interpreted in terms of magma ascent using the models proposed by Nuccio & Paonita, (2001) and Caracausi et al. (2003). On the basis of numerical simulations of volatile degassing, we have been able to recognize episodes of magma migration from deeper reservoirs of Mount Etna to the shallower storage volume, until magma is erupted. The 3He/4He isotope ratios of gas emitted at the periphery of Mount Etna volcanic edifice exhibit sy…
Active Geodynamics of the Central Mediterranean Sea: tensional tectonic evidences in western Sicily from mantle-derived helium.
We report results on the measured high 3He/4He isotope ratio in western Sicily, interpreted together with the heat data. The study of this sector of the Europe-Africa interaction is crucial to a better understanding of the tectonics and the geodynamical evolution of the central Mediterranean area. The estimated mantle-derived helium fluxes in the investigated areas are up to 2-3 orders of magnitude greater than those of a stable continental area. The highest flux, found in the southernmost area near the Sicily Channel, where recent eruptions of the Ferdinandea Island occurred 20 miles out to sea off Sciacca, has been associated with a clear excess of heat flow. Our results indicate that the…