The Stanley Pool, an almost circular island about
thirty kilometers in diameter, crossed by the Congo River, is subject to
diversified erosion of its riverbanks. This study highlights description using
geotechnical particle size distribution analysis of soils of the shoreline that
make up the shoreline. Three critical areas of the island were examined to
characterize the origins of these erosion phenomena. The results obtained show
that the soil materials are mostly sands with very fine or fine grains
characteristic of very unstable soils. The morpho-sedimentological characteristics of the areas studied show that these
soils are plastic (with a Plasticity Index between 15 percent and 19 percent). The presence of water, action of currents or groundwater flow easily
destabilize the materials that make up the riverbank and cause the fines to
creep (Collapse of sandy riverbanks, Landslide of sandy riverbanks,…).
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