Tracking paraglacial sediment with cosmogenic ¹⁰Be using an example from the northwest Scottish Highlands

Beryllium-10 concentrations in samples of sediment and bedrock from five study sites across the Scottish Highlands trace paraglacial sediment sources and define the nature of glacial erosion for the late Quaternary. Exposure ages derived from ¹⁰Be concentrations in ridge and lower elevation bedrock range from 10 to 33 ka, which suggest that polythermal ice and warm based ice were primarily responsible for producing glacial sediment. Comparisons of ¹⁰Be concentrations between catchment-wide sediment (2.06 ± 0.34 × 10⁴ to 11.24 ± 1.54 × 10⁴ atoms g⁻¹ SiO₂; n = 33), near surface deposits (2.71 ± 0.33 × 10⁴ to 3.48 ± 0.49 × 10⁴ atoms g⁻¹ SiO₂; n = 6), 4-m-thick deep till (0.68 × 10^{4 10}Be atoms g⁻¹ SiO₂; n = 1), ridge bedrock (8.93 ± 0.47 × 10⁴ to 34.05 ± 1.66 × 10⁴ atoms g⁻¹ SiO_2; n = 20), and lower elevation polished bedrock (6.74 ± 0.67 × 10⁴ to 12.65 ± 0.7 × 10⁴ atoms g⁻¹ SiO₂, n = 5) indicate that most sand fluxing through catchments in the Scottish Highlands is sourced from the remobilization and vertical mixing of near surface deposits. These findings indicate that glaciogenic material continues to dominate paraglacial sediment budgets more than 11 ka after deglaciation.