Control of silicate weathering by interface-coupled dissolution-precipitation processes at the mineral-solution interface

Research Article| July 01, 2016 Control of silicate weathering by interface-coupled dissolution-precipitation processes at the mineral-solution interface Encarnación Ruiz-Agudo; Encarnación Ruiz-Agudo * 1Departamento de Mineralogía y Petrología, Universidad de Granada, 18071 Granada, Spain *E-mail: encaruiz@ugr.es Search for other works by this author on: GSW Google Scholar Helen E. King; Helen E. King 2Department of Earth Sciences, Utrecht University, 3584 CD Utrecht, Netherlands Search for other works by this author on: GSW Google Scholar Luis D. Patiño-López; Luis D. Patiño-López 3Centro de Investigación Científica de Yucatán, 97302 Mérida, México Search for other works by this author on: GSW Google Scholar Christine V. Putnis; Christine V. Putnis 4Institut für Mineralogie, Universität Münster, 48149 Münster, Germany5Nanochemistry Research Institute, Department of Chemistry, Curtin University, Perth, WA 6845, Australia Search for other works by this author on: GSW Google Scholar Thorsten Geisler; Thorsten Geisler 6Steinmann Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, 53115 Bonn, Germany Search for other works by this author on: GSW Google Scholar Carlos Rodriguez-Navarro; Carlos Rodriguez-Navarro 1Departamento de Mineralogía y Petrología, Universidad de Granada, 18071 Granada, Spain Search for other works by this author on: GSW Google Scholar Andrew Putnis Andrew Putnis 4Institut für Mineralogie, Universität Münster, 48149 Münster, Germany7The Institute for Geoscience Research (TIGeR), Curtin University, Perth, WA 6845, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information Encarnación Ruiz-Agudo * 1Departamento de Mineralogía y Petrología, Universidad de Granada, 18071 Granada, Spain Helen E. King 2Department of Earth Sciences, Utrecht University, 3584 CD Utrecht, Netherlands Luis D. Patiño-López 3Centro de Investigación Científica de Yucatán, 97302 Mérida, México Christine V. Putnis 4Institut für Mineralogie, Universität Münster, 48149 Münster, Germany5Nanochemistry Research Institute, Department of Chemistry, Curtin University, Perth, WA 6845, Australia Thorsten Geisler 6Steinmann Institut für Geologie, Mineralogie und Paläontologie, University of Bonn, 53115 Bonn, Germany Carlos Rodriguez-Navarro 1Departamento de Mineralogía y Petrología, Universidad de Granada, 18071 Granada, Spain Andrew Putnis 4Institut für Mineralogie, Universität Münster, 48149 Münster, Germany7The Institute for Geoscience Research (TIGeR), Curtin University, Perth, WA 6845, Australia *E-mail: encaruiz@ugr.es Publisher: Geological Society of America Received: 01 Mar 2016 Revision Received: 19 May 2016 Accepted: 20 May 2016 First Online: 02 Jun 2017 Online Issn: 1943-2682 Print Issn: 0091-7613 © 2016 Geological Society of America Geology (2016) 44 (7): 567–570. https://doi.org/10.1130/G37856.1 Article history Received: 01 Mar 2016 Revision Received: 19 May 2016 Accepted: 20 May 2016 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 Encarnación Ruiz-Agudo, Helen E. King, Luis D. Patiño-López, Christine V. Putnis, Thorsten Geisler, Carlos Rodriguez-Navarro, Andrew Putnis; Control of silicate weathering by interface-coupled dissolution-precipitation processes at the mineral-solution interface. Geology 2016;; 44 (7): 567–570. doi: https://doi.org/10.1130/G37856.1 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 mechanism of surface coating formation (the so-called surface altered layers [SALs] or leached layers) during weathering of silicate minerals is controversial and hinges on understanding the saturation state of the fluid at the dissolving mineral surface. Here we present in-situ data on the evolution of the interfacial fluid composition during dissolution of wollastonite (CaSiO3), obtained using interferometry and micro pH and ion-selective electrodes. Steep concentration gradients develop at the mineral interface as soon as it makes contact with the solution. This interfacial fluid becomes supersaturated with respect to amorphous silica that forms a surface coating, limiting fluid access to the mineral surface and hence affecting the dissolution rate. The thickness of the supersaturated zone and the precipitated layer depends on the relative rates of mass transport and surface reaction in the system; this effect could contribute to the discrepancy between dissolution rates measured in the field and in the laboratory. As well, our results have implications for predictions of silicate weathering rates and hence climate evolution, as different assumptions on dissolution mechanisms affect calculations on CO2 drawdown during weathering and consequent effects on estimates of global mean temperatures. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.