Nature Does The Averaging-In-Situ Produced Be-10, Ne-21, And Al-26 In A Very Young River Terrace

The concentrations of long-lived in-situ produced cosmogenic nuclides (Be-10,Ne-21,Al-26) in quartz obtained from a very recent (similar to 200 a; based on C-14 data on organic material) terrace of the Swakop River in Namibia are nearly constant throughout a 322 cm-long depth profile. These findings corroborate earlier hypotheses postulating a homogeneous distribution of these nuclides in freshly deposited river terrace sediments. An averaged nuclide concentration is a crucial and generally assumed prerequisite for the determination of numerical ages of old sediments.