Publication Date:
2017-04-04
Description:
Mount Etna is a huge volcano in the Mediterranean basin and is located in the eastern part of
Sicily. It is considered to be, on the long-term average, the major atmospheric point source of
many environmental harmful compounds. Their emission occurs either through continuous
passive degassing from open-conduit activity or through sporadic paroxysmal eruptive
activity, in the form of gases, aerosols or particulate. Volcanic volatiles and aerosol emitted
into the atmosphere fall on the Earth’s surface as wet or dry deposition, and can influence
the environment both at local and regional scale.
To estimate the environmental impact of magma-derived trace metals and their depositions
processes, bulk deposition samples have been collected approximately fortnightly, using a
network of 5 rain gauges located at various altitudes on the upper flanks close to the summit
craters, from April 2006 to December 2007. Samples were analyzed for the main chemicalphysical
parameters (electric conductivity and pH) and for major and trace elements
concentrations.
The data obtained clearly show that the volcanic contribution is always prevailing in the
sampling site closest to the summit craters (∼1.5 km). In the distal sites (5.5-10 km from the
summit) and downwind of the summit craters, the volcanic contribution is also detectable
but often overwhelmed by anthropogenic or other natural (seawater spray, geogenic dust)
contributions. Volcanogenic contribution may derive from both dry and wet deposition of
gases and aerosols from the volcanic plume, but sometimes also from leaching of freshly
emitted volcanic ashes. In fact, in our background site (7.5 km in the upwind direction), after
an ash deposition event high concentration of lithophiles elements (Si, Al, Fe, Ti) have been
measured.
Sulphur, Chlorine and Fluorine, represent the main constituents that characterize the
volcanic contribution in the bulk deposition on Mt. Etna, although high concentrations of
many trace elements (Si, Al, Fe, Ti, Cu, As, Rb, Pb, Tl, Cd, Cr, U and Ag) display, in the site
most exposed to the volcanic emissions, average concentrations of about two orders of
magnitude higher than those measured in the background site (Mount Intraleo).
Description:
Published
Description:
Catania, Italy
Description:
4.5. Degassamento naturale
Description:
open
Keywords:
Mt. Etna
;
trace elements
;
rainwater
;
01. Atmosphere::01.01. Atmosphere::01.01.07. Volcanic effects
;
03. Hydrosphere::03.03. Physical::03.03.01. Air/water/earth interactions
;
03. Hydrosphere::03.04. Chemical and biological::03.04.03. Chemistry of waters
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Oral presentation
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