Observation of manganese deposits in the Southern Ocean during the R/V Polarstern ANT-IX/3 and ANT-IX/4 expeditions

On a previous R/V Polarstern cruise ANT-VIII/5 (1989/90), a deep-sea area in the central Weddell Sea was investigated along geophysical and bathymetrical transects. As a result, a seamount-like structure, the informally named "Polarstern Seamount", was detected. This seamount was one of the sampling areas during the ANT-IX/3 leg. Attempts were made to retrieve glaciomarine and hemipelagic sediments, which in this area were expected not to be so strongly affected by bottom currents as are the sediments in the deeper surroundings seas. The seafloor on top of the Polarstern Searnount revealed to be densely covered with Mn encrusted dropstones, as observed by the underwater video-recording obtained from a camera installed at the multi box corer (MG), as well as in the retrieved sediments.