Please use this identifier to cite or link to this item:
|Authors: ||Viveiros, F.*|
|Title: ||Soil CO2 emissions at Furnas volcano (São Miguel Island, Azores archipelago) - volcano monitoring perspectives, geomorphologic studies and land-use planning application|
|Title of journal: ||J.Geophysical Research|
|Issue Date: ||2010|
|Keywords: ||Soil CO2 emissions|
|Abstract: ||Carbon dioxide (CO2) diffuse degassing structures (DDS) at Furnas Volcano (São
Miguel Island, Azores) are mostly associated with the main fumarolic fields, evidence
that CO2 soil degassing is the surface expression of rising steam from the hydrothermal
system. Locations with anomalous CO2 flux are mainly controlled by tectonic structures
oriented WNW-ESE and NW-SE and by the geomorphology of the volcano, as
evidenced by several DDS located in depressed areas associated with crater margins.
Hydrothermal soil CO2 emissions in Furnas volcano are estimated to be ~ 968 t d-1.
Discrimination between biogenic and hydrothermal CO2 was determined using a
statistical approach and the carbon isotope composition of the CO2 efflux. Different
sampling densities were used to evaluate uncertainty in the estimation of the total CO2
flux, and showed that a low density of points may not be adequate to quantify soil
emanations from a relatively small DDS. Thermal energy release associated to diffuse
degassing at Furnas caldera is about 118 MW (from an area of ~ 4.8 km2) based on the
H2O/CO2 ratio in fumarolic gas. The DDS affect also Furnas and Ribeira Quente
villages, which are located inside the caldera and in the south flank of the volcano,
respectively. At these sites, 58% and 98% of the houses are built over hydrothermal
CO2 emanations, and the populations are at risk due to potential high concentrations of
CO2 accumulating inside the dwellings.
Keywords: Soil diffuse degassing; soil CO2 flux; emission rates; Azores archipelago
|Description: ||Accepted for publication in Journal of Geophysical Research. Copyright (2010) American Geophysical Union.|
|Appears in Collections:||04.04.11. Instruments and techniques|
04.04.12. Fluid Geochemistry
Papers Published / Papers in press
Files in This Item:
|Soil CO2 emissions at Furnas volcano (San Miguel Island, Azores archipelago).pdf||4.16 MB||Adobe PDF||View/Open
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.