Recent erosional history of a soil profile based on cosmogenic in-situ radionuclides ¹⁴C and ¹⁰Be

We present here results of measurements of cosmogenic in-situ produced ¹⁴C and ¹⁰Be in a quartz vein in a soil profile near Reston (Virginia, USA). Assuming that the quartz vein suffered mass wastage soon after any exposure resulting from soil erosion, we obtain model erosion rates of ≥3 × 10^-3 and ≤3 × 10^-4 cm yr^-1 for the nuclides ¹⁴C and ¹⁰Be respectively. The implications of these results are discussed both in terms of plausible recent erosion histories of the soil profile, and also the applicability of the quartz vein method and its variants for determining soil erosion rates. We conclude that the two radionuclides together should generally prove useful for determining soil erosion rates in quartz containing rock fragments. By itself, the nuclide ¹⁴C should be useful for determining erosion rates exceeding -5 × 10^-2 cm yr^-1.