Water Resources of the Caribbean
Denudation rates determined from the accumulation of in situ-produced 10Be in the Luquillo Experimental Forest, Puerto Rico
Erik Thorson Brown 1, Robert F. Stallard 2, Matthew C. Larsen 2, Grant M. Raisbeck 1, Francoise Yiou 1
1(CNRS-IN2P3, CSNSM, Batiment 108, 91405 Campus Orsay, France; tel. (33 1) 69 41 5203;e-mail email@example.com)
2(U.S. Geological Survey, 3215 Marine St., Boulder, CO 80303-1066, USA; tel. 303 541-3022)
We present a simple method for estimation of long-term mean denudation rates using in situ-produced cosmogenic 10Be in fluvial sediments. Procedures are discussed to account for the effects of soil bioturbation, mass wasting and attenuation of cosmic rays by biomass and by local topography. Our analyses of 10Be in quartz from bedrock outcrops, soils, mass-wasting sites and riverine sediment from the Icacos River basin in the Luquillo Expenmental Forest, Puerto Rico, are used to characterize denudation for major landform elements in that basin. The 10Be concentration of a discharge-weighted average of size classes of river sediment corresponds to a long-term average denudation of ~ 43 m/Ma, consistent with mass balance results.
Brown, E.T., Stallard, R.F., Larsen, M.C., Raiseck, G.M., and Yiou, F. 1995, Denudation rates determined from the accumulation of in situ produced 10Be in the Luquillo Experimental Forest: Puerto Rico: Earth and Planetary Science Letters, vol. 129, p. 193-202.