Granulometry of sediments collected by differently inclined sediment traps in Comau Fjord

The meltwater reaching Chile's Comau Fjord carries glacial sediment, resulting in a high sediment input in the fjord system. To record the sedimentary material, sediment traps (0.5 m long PVC pipes closed at the bottom end, diameter 0.05 m) were attached at different angles of inclination to large concrete pipes with screw clamps. After four weeks, these were sealed and recovered by research divers. The sediment was transferred to vessels for sedimentation and the clear supernatant was removed 48 hours later. The remaining sediment-seawater mixture was fixed with formol (final concentration 4%). Samples were treated with hydrogen peroxide and acetic acid to remove organic content. For particle size determination, samples were analysed using a Laser Particle Analyser (Cilias, Quantachrome Cilas 1180 Particle Analyser, Orleans, France). In this method, the grain size is measured based on the different diffraction of a laser beam on the particles. The evaluation of the laser granulometry took place using Gradistat software (Kenneth Pye Assocates LTD., Gradistat 8.0, Solihull, UK). Data are given in volume percentage (error < 1%).