10Be analysis of a Quaternary weathering profile in the Virginia Piedmont
Samples from a residual weathering profile in the Virginia Piedmont have been analyzed for cosmogenic 10Be. Concentrations are highest in clay-rich soil and decrease exponentially to a depth of about 15 m. Despite uncertainties about the processes by which 10Be may be intercepted before entering the solum and eroded after incorporation, a minimum age may be calculated for the regolith. This calculation is based on the delivery rate of 10Be and its decay rate and suggests that this residual profile developed during a period no shorter than 8 × 105 yr. The calculated minimum age may be within a factor of 2 of maximum-age estimates based on surface lowering by erosion and on the rate of rock weathering to saprolite. The vertical distribution of 10Be in the profile could result from a steady-state balance of deposition, weathering, radioactive decay, and erosion.
Citation Information
Publication Year | 1985 |
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Title | 10Be analysis of a Quaternary weathering profile in the Virginia Piedmont |
DOI | 10.1130/0091-7613(1985)13<39:BAOAQW>2.0.CO;2 |
Authors | M.J. Pavich, Louis Brown, J. Nathalie Valette-Silver, Jeffrey Klein, Roy Middleton |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Geology |
Index ID | 70013108 |
Record Source | USGS Publications Warehouse |