Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
Geology Signup for GSW Email News
JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Geology; February 2008; v. 36; no. 2; p. 159-162; DOI: 10.1130/G24360A.1
© 2008 Geological Society of America
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Codilean, A. T.
Right arrow Articles by Freeman, S. P.H.T.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation

Single-grain cosmogenic 21Ne concentrations in fluvial sediments reveal spatially variable erosion rates

Alexandru T. Codilean*,1, Paul Bishop1, Finlay M. Stuart2, Trevor B. Hoey3, Derek Fabel3 and Stewart P.H.T. Freeman4

1 Department of Geographical & Earth Sciences, University of Glasgow, Glasgow G12 8QQ, UK
2 Scottish Universities Environmental Research Centre (SUERC), East Kilbride G75 0QF, UK
3 Department of Geographical & Earth Sciences, University of Glasgow, Glasgow G12 8QQ, UK
4 Scottish Universities Environmental Research Centre (SUERC), East Kilbride G75 0QF, UK

We evaluated the hypothesis that the spatial variation in erosion in a catchment is reflected in the distribution of the cosmogenic nuclide concentrations in sediments leaving the catchment. Using published data and four new 10Be measurements in fluvial sediment collected from the outlets of small river catchments, we constrained the spatial variability of erosion rates in the Gaub River catchment in Namibia. We combined these catchment-averaged erosion rates, and the mean slope values with which they are associated, in a digital elevation model (DEM)–based analysis to predict distributions of cosmogenic 21Ne concentrations in the sediment leaving the Gaub catchment. We compared these synthetic distributions with the distribution of concentrations of cosmogenic 21Ne (21NeC) in 32 quartz fluvial pebbles (16–21 mm) collected from the catchment outlet. The 21NeC concentrations span nearly two orders of magnitude (2.6–160 x 106 atoms/g) and are highly skewed toward low values. The DEM-based analysis confirms this skew—the measured 21NeC distribution plots within the envelope of distributions predicted for the catchment. This match between measured and synthetic 21Ne distributions implies that the measured distribution is a signature of the spatial variation in erosion rates.

Key Words: 21Ne • 10Be • cosmogenic nuclides • denudation rates • slope dependence • landscape evolution






JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2008 by Geological Society of America