Fluxes and origin of halogenated organic trace gases from Momotombo volcano (Nicaragua).

Frische, Matthias, Garofalo, Kristin, Hansteen, Thor and Borchers, R. (2006) Fluxes and origin of halogenated organic trace gases from Momotombo volcano (Nicaragua). Open Access Geochemistry Geophysics Geosystems, 7 (5). Q05020. DOI 10.1029/2005GC001162.

[img]
Preview
Text
Frische_et_al-2006-Geochemistry,_Geophysics,_Geosystems.pdf - Published Version

Download (670Kb) | Preview

Supplementary data:

Abstract

In order to assess the contribution of quiescent degassing volcanoes to the global halo(hydro)carbon inventory, we have quantified volcanic fluxes of methyl halides (CH3Cl, CH3Br, and CH3I), ethyl halides (C2H5Cl, C2H5Br, and C2H5I), and higher chlorinated methanes (CH2Cl2, CHCl3, and CCl4). About every eight months over a 2-year period (July 2001 to July 2003), gas samples were collected and analyzed from high-temperature fumaroles (472°C–776°C) at the Nicaraguan subduction zone volcano Momotombo. Using a simultaneous record of trace and main compounds in fumarolic gases as well as SO2 fluxes of the plume, we were able to calculate halo(hydro)carbon fluxes for Momotombo and extrapolate our results to estimate halo(hydro)carbon fluxes for the whole Quaternary Nicaraguan volcanic arc and, in addition, for all volcanoes globally. The most abundant halohydrocarbon was CH3Cl with concentrations up to 19 ppmv. Further major halo(hydro)carbons were CH3Br, CH3I, CH2Cl2, CHCl3, CCl4, C2H5Cl, C2H5Br, C2H5I, and C2H3Cl with an average concentration of 0.20 to 720 ppbv. Estimated mean halo(hydro)carbon fluxes from Momotombo were in the range of 630–5000 g/yr for methyl halides, 49–260 g/yr for ethyl halides, and 2.4–24 g/yr for higher chlorinated methanes. When the results for Momotombo are scaled up to SO2 fluxes of the Nicaraguan volcanic transect, fluxes of 1.7 × 105 g/yr CH3Cl and 82 g/yr CCl4 are attained for Nicaragua. Scaled up to the estimated global SO2 flux, this translates to hypothetical global fluxes of 5.6 × 106 g/yr CH3Cl and 2.7 × 103 g/yr CCl4. These volcanic fluxes are negligible compared to global anthropogenic and natural emissions of about 3 × 1012 g/yr CH3Cl and 2 × 1010 g/yr CCl4.

Document Type: Article
Keywords: trace gases, halohydrocarbons, subduction zones, fumaroles, quiescent degassing, Momotombo
Research affiliation: OceanRep > SFB 574 > C5
OceanRep > SFB 574 > C3
OceanRep > SFB 574
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-MUHS Magmatic and Hydrothermal Systems
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1029/2005GC001162
ISSN: 1525-2027
Contribution Number:
ProjectNumber
SFB 57485
Expeditions/Models/Experiments:
Date Deposited: 06 Oct 2009 16:52
Last Modified: 27 Feb 2018 08:42
URI: http://oceanrep.geomar.de/id/eprint/1682

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...