Comparison of Geochemical and Geotechnical Sediment Baseline Profiles of COMRA (CCFZ) and TUSCH (Peru Basin) Study Areas within the Scope of Mn-Nodule Mining

摘要

A representative number of sediment surface cores from the COMRA pioneer areas (tropical NE-Pacific) were analyzed for pore-water and solid-phase heavy-metal and nutrient concentrations, vane shear-strengths, and re-suspension/re-sedimentation behavior, in comparison with similar cores from TUSCH study areas (Peru Basin, tropical E-Pacific). Geochemically, technical interventions in the NE-Pacific areas would cause less environmental changes because of significantly lower potential of pollutant release. Soil-mechanical conditions generally seem to be similar in both regions, except for locally higher variability in COMRA's Western Area. Preliminary results of re-suspension experiments indicated that the re-sedimentation process depends mainly on the particle concentration in suspension.