For the sampling of deep-sea sediments we use a multiple corer (MUC) and a giant box corer (GBC). These devices were lowered to the seafloor by the ships wire to collect sediment cores of different sizes.
The MUC was developed at SMBA Dunstaffnage Marine Research Laboratory (Scotland, UK). It consists basically of three units, a supporting framework a hydraulic damper, and a supporting a sliding framework which carries an assembly of core sampling tubes. Each tube takes a core sample of 60 to 100 mm in diameter, and about 60 cm in length. The tubes are made out of transparent plastic to allow for visual inspection of the samples. A special mechanism closes valves on the top of each tube and releases bottom core catchers which help to retain the cores from beneath during the ascent to the surface.
The GBC was developed at the Scripps Institute of Oceanography (California, USA) in collaboration with the United States Naval Electronic Laboratory (USNEL). The gear consists out of a supporting frame and a central sliding frame work carrying a metal box of 50 x 50 cm, which can retrieve seafloor samples down to 50 cm sediment depth. A spade closes the box from beneath during the recovery of the instrument.
Whereas the MUC is preliminary used to collect the small sediment-inhabiting organisms, the GBC is usually utilized to quantitatively assess larger organism size classes.
Contact: J. Dannheim, C. Hasemann