Irregular isograds, reaction instabilities, and the evolution of permeability during metamorphism

Research Article| January 01, 1998 Irregular isograds, reaction instabilities, and the evolution of permeability during metamorphism Nathalie Marchildon; Nathalie Marchildon 1Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, B.C. V6T 1Z4, Canada Search for other works by this author on: GSW Google Scholar Gregory M. Dipple Gregory M. Dipple 1Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, B.C. V6T 1Z4, Canada Search for other works by this author on: GSW Google Scholar Geology (1998) 26 (1): 15–18. https://doi.org/10.1130/0091-7613(1998)026<0015:IIRIAT>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Nathalie Marchildon, Gregory M. Dipple; Irregular isograds, reaction instabilities, and the evolution of permeability during metamorphism. Geology 1998;; 26 (1): 15–18. doi: https://doi.org/10.1130/0091-7613(1998)026<0015:IIRIAT>2.3.CO;2 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 Numerical models of two-dimensional heterogeneous reactive transport of H2O-CO2 fluid and oxygen isotopes were developed to investigate the heterogeneity of fluid flow and permeability attending contact metamorphism of siliceous dolomites. Comparison of results with observations from the Alta (Utah) contact aureole indicates that both mineral reactions and isotopic alteration record fluid flow through highly heterogeneous permeability. We interpret this extreme heterogeneity to be the result of positive feedback between reaction enhancement of permeability and flow-focusing. Similar distributions of mineral assemblages and stable isotopic alteration in other aureoles suggest that this is a common mechanism of permeability evolution during contact metamorphism of carbonate rocks. Flow-focusing requires fast reaction rates and slow compaction relative to fluid flow. More homogeneous permeability recorded in regional metamorphic rocks may reflect fundamental differences in the relative rates of fluid flow and compaction in regional and contact metamorphic environments. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.