초록 close

Deep-sea surface sediments, acquired from 1997 to 2002 in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific, were analyzed for index and geotechnical properties to provide background information for the design of manganese nodule minor. The sediments were classified into 16 types based on the measured properties and evaluated in terms of miner maneuverabillity and potential environmental impacts arising from mining activities. It was found that the middle part of the study area covered with coarse siliceous sediments is more favorable to the commercial production than the northern part of pelagic red clay. In particular, Area B2 in the middle part is considered the best mining site since it shows the highest abundance as well as it consists mostly of normally to over consolidated (types B,C,D) coarse siliceous sediments that are appropriate for effective minor movement and accompany weak environmental impacts. Taking account of all the analyzed core logs, the average shear-strength values are proposed as a practical guideline for movements of a manganese nodule miner: 6.0 kPa at 10 cm and 7.0 kPa at 40 cm below the seabed.