Oxygen isotope zoning profiles in hydrothermally altered feldspars: Estimating the duration of water-rock interaction

Abstract

Research Article| January 01, 2004 Oxygen isotope zoning profiles in hydrothermally altered feldspars: Estimating the duration of water-rock interaction David R. Cole; David R. Cole 1Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA Search for other works by this author on: GSW Google Scholar Peter B. Larson; Peter B. Larson 2Department of Geology, Washington State University, Pullman, Washington 99164-2812, USA Search for other works by this author on: GSW Google Scholar Lee R. Riciputi; Lee R. Riciputi 3Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA Search for other works by this author on: GSW Google Scholar Claudia I. Mora Claudia I. Mora 4Department of Geological Sciences, University of Tennessee, Knoxville, Tennessee 37996-1410, USA Search for other works by this author on: GSW Google Scholar Author and Article Information David R. Cole 1Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA Peter B. Larson 2Department of Geology, Washington State University, Pullman, Washington 99164-2812, USA Lee R. Riciputi 3Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA Claudia I. Mora 4Department of Geological Sciences, University of Tennessee, Knoxville, Tennessee 37996-1410, USA Publisher: Geological Society of America Received: 03 Jun 2003 Revision Received: 24 Sep 2003 Accepted: 29 Sep 2003 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2004) 32 (1): 29–32. https://doi.org/10.1130/G19881.1 Article history Received: 03 Jun 2003 Revision Received: 24 Sep 2003 Accepted: 29 Sep 2003 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation David R. Cole, Peter B. Larson, Lee R. Riciputi, Claudia I. Mora; Oxygen isotope zoning profiles in hydrothermally altered feldspars: Estimating the duration of water-rock interaction. Geology 2004;; 32 (1): 29–32. doi: https://doi.org/10.1130/G19881.1 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 characterization of intragrain mineralogical and isotopic zoning patterns provides the basis for estimating the duration of fluid-rock interaction associated with mineral replacement reactions. In the Rico, Colorado, hydrothermal system, oxygen isotope ratios in reaction rims on partially reacted plagioclase feldspar exhibit some of the largest gradients yet reported for individual grains (to 15‰). The extent of rim formation and accompanying isotopic exchange vary across the system as a function of temperature, fluid isotope composition, and the local fluid/rock ratio. Distal feldspars show narrow rims with 18O enrichments relative to pristine feldspars. Feldspars intermediate or proximal to the system's center have wide reaction rims or are completely exchanged and show 18O depletions. Formation times of reaction rims and associated isotopic patterns have been estimated with a coupled reaction-diffusion model that suggests that hotter (∼250–350 °C) hydrothermal circulation was active for ∼100–300 k.y. in the center part of the system, perhaps only while the igneous heat engine was still magma. Cooler (∼150–200 °C) circulation was widespread, lasting for >1000 k.y. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.