A theoretical model coupling chemical weathering rates with denudation rates

Research Article| February 01, 2009 A theoretical model coupling chemical weathering rates with denudation rates Emmanuel J. Gabet; Emmanuel J. Gabet 1Department of Geology, San Jose State University, San Jose, California 95192, USA Search for other works by this author on: GSW Google Scholar Simon M. Mudd Simon M. Mudd 2School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK Search for other works by this author on: GSW Google Scholar Author and Article Information Emmanuel J. Gabet 1Department of Geology, San Jose State University, San Jose, California 95192, USA Simon M. Mudd 2School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK Publisher: Geological Society of America Received: 18 Jun 2008 Revision Received: 22 Sep 2008 Accepted: 09 Oct 2008 First Online: 12 Oct 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2009 Geological Society of America Geology (2009) 37 (2): 151–154. https://doi.org/10.1130/G25270A.1 Article history Received: 18 Jun 2008 Revision Received: 22 Sep 2008 Accepted: 09 Oct 2008 First Online: 12 Oct 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Emmanuel J. Gabet, Simon M. Mudd; A theoretical model coupling chemical weathering rates with denudation rates. Geology 2009;; 37 (2): 151–154. doi: https://doi.org/10.1130/G25270A.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 Uplift of the Himalayas has been proposed to have locally accelerated chemical weathering, thus leading to enhanced CO2 sequestration and global cooling. This hypothesis assumes that rapid erosion exposes fresh, highly reactive minerals at Earth's surface. Empirical studies quantifying the relationship between erosion and weathering have produced apparently conflicting results, where the nature of the relationship is dependent on the weathering regime of the sampled landscapes. We derive a quantitative model that defines this relationship across the range of weathering regimes, from supply-limited to kinetically limited conditions. The model matches trends in field data collected by others and reconciles apparently conflicting results. The model also demonstrates that, as erosion rates increase, potential increases in weathering rate from the exposure of fresher materials are offset by the decrease in the total volume of minerals exposed due to thinner regolith. We conclude that the relationship between weathering and erosion is one of diminishing returns, in which increases in erosion rate lead to progressively smaller increases in weathering rate; indeed, at the highest erosion rates, weathering rates may decline. The ability, therefore, of accelerated uplift and erosion to stimulate greater CO2 sequestration may be significant in landscapes eroding at rates of 100–102 t km−2 yr−1. However, where erosion rates are greater than 102 t km−2 yr−1, increases in denudation may not be matched by increases in chemical weathering. Finally, our results suggest that watersheds with regolith thicknesses of ~0.5 m will yield the greatest solute fluxes. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.