Friday 24 April: Refining our target
As our soil sampling has proceeded, we've been able to refine our
visual target for sites. We're trying to find sites that naturally
collect sediment from a significant uphill area with both human
occupation and agriculture. As we've proceeded, our skill has improved
at finding sites that collect sediment efficiently without being
scoured out during major floods. This site was nearly ideal. It
samples a large area upstream of gorge in the background. The exact
location we sampled showed evidence of almost continuous soil burial,
but had to be chosen carefully because areas directly downstream of
the gorge appeared to be scoured out during floods.
In the sample shown, the core is composed entirely of material dark
enough to be a topsoil, but the sample is from 1.2 - 1.5 m below the
soil surface. Throughout most of the island, soils at this depth would
be light reddish brown.
