Flux rates for water and carbon during greenschist facies metamorphism

Research Article| January 01, 2011 Flux rates for water and carbon during greenschist facies metamorphism Alasdair Skelton Alasdair Skelton Department of Geological Sciences, Stockholm University, 106 91 Stockholm, Sweden Search for other works by this author on: GSW Google Scholar Author and Article Information Alasdair Skelton Department of Geological Sciences, Stockholm University, 106 91 Stockholm, Sweden Publisher: Geological Society of America Received: 26 Apr 2010 Revision Received: 02 Aug 2010 Accepted: 07 Aug 2010 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2011 Geological Society of America Geology (2011) 39 (1): 43–46. https://doi.org/10.1130/G31328.1 Article history Received: 26 Apr 2010 Revision Received: 02 Aug 2010 Accepted: 07 Aug 2010 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Alasdair Skelton; Flux rates for water and carbon during greenschist facies metamorphism. Geology 2011;; 39 (1): 43–46. doi: https://doi.org/10.1130/G31328.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The time-averaged flux rate for a CO2-bearing hydrous fluid during greenschist facies regional metamorphism was estimated to be 10–10.2 ± 0.4 m3 m−2 s−1 by combining (1) Peclet numbers obtained by chromatographic analysis of the propagation of reaction fronts in 33 metamorphosed basaltic sills in the southwest Scottish Highlands (UK), (2) empirical diffusion rates for CO2 in water, and (3) calculated time-averaged metamorphic porosities. The latter were calculated using an expression obtained by combining estimated Peclet numbers with empirical porosity-permeability relationships and Darcy's law. This approach yielded a time-averaged metamorphic porosity of 10–2.6 ± 0.2 for greenschist facies conditions. The corresponding time scale for metamorphic fluid flow was 103.6 ± 0.1 yr. By using mineral assemblages to constrain fluid compositions, a time-averaged annual flux rate for carbon of 0.5–7 mol C m−2 yr−1 was calculated. This matches measured emission rates for metamorphic CO2 from orogenic hot springs and exceeds estimated rates of CO2 drawdown by orogenic silicate weathering, suggesting that orogenesis is a source rather than a sink of atmospheric CO2. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.