Using meteoric 10Be to track fluvial sand through the Waipaoa River basin, New Zealand

Abstract

Research Article| January 01, 2010 Using meteoric 10Be to track fluvial sand through the Waipaoa River basin, New Zealand Lucas J. Reusser; Lucas J. Reusser * Rubenstein School of Environment and Natural Resources and Department of Geology, University of Vermont, Burlington, Vermont 05405, USA *E-mail: lreusser@uvm.edu. Search for other works by this author on: GSW Google Scholar Paul R. Bierman Paul R. Bierman Rubenstein School of Environment and Natural Resources and Department of Geology, University of Vermont, Burlington, Vermont 05405, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Lucas J. Reusser * Rubenstein School of Environment and Natural Resources and Department of Geology, University of Vermont, Burlington, Vermont 05405, USA Paul R. Bierman Rubenstein School of Environment and Natural Resources and Department of Geology, University of Vermont, Burlington, Vermont 05405, USA *E-mail: lreusser@uvm.edu. Publisher: Geological Society of America Received: 18 May 2009 Revision Received: 27 Jul 2009 Accepted: 31 Jul 2009 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2010 Geological Society of America Geology (2010) 38 (1): 47–50. https://doi.org/10.1130/G30395.1 Article history Received: 18 May 2009 Revision Received: 27 Jul 2009 Accepted: 31 Jul 2009 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Lucas J. Reusser, Paul R. Bierman; Using meteoric 10Be to track fluvial sand through the Waipaoa River basin, New Zealand. Geology 2010;; 38 (1): 47–50. doi: https://doi.org/10.1130/G30395.1 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 We use meteoric 10Be measured in 24 fluvial sand samples collected along the mainstem and from prominent tributaries within the tectonically active Waipaoa River basin, New Zealand, to identify sediment sources and monitor the mixing of sediment as it travels from headwater basins to the sea. Deforestation for agriculture beginning in the early 1900s resulted in severe, but nonuniformly distributed erosion. Tributaries in the northern headwaters, where large amphitheater gullies that continually feed prodigious amounts of deeply sourced sediment to the mainstem are prevalent, yield exceptionally low concentrations of meteoric 10Be (∼1.5 × 106 atoms g−1). In the more stable eastern and western tributaries, concentrations of meteoric 10Be are nearly an order of magnitude greater (∼14 × 106 atoms g−1). Meteoric 10Be concentrations in samples collected along the mainstem above and below tributary confluences steadily and regularly increase downstream (R2 = 0.92) as large amounts of low-concentration gully-derived sediments are augmented with higher concentration sediment from more stable tributaries, providing strong evidence that meteoric 10Be concentrations reflect sediment sourcing in this fluvial network. A two-component mixing model indicates that the gullied northern region of the Waipaoa basin produces sediment at a rate ∼20 times that of the eastern and western regions. These results suggest that meteoric 10Be, in contrast to the widely applied in situ technique that is limited by the availability and distribution of quartz, is an effective tool for the rapid assessment of sediment dynamics and movement within a wide range of fluvial networks. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.