Box corer

Box corer

The Box corer is a marine geological sampling tool for soft sediments in lakes or oceans. It is deployed from a research vessel with a deep sea wire and suitable for any water depth. It is designed for a minimum of disturbance of the sediment surface by bow wave effects which is important for quantitative investigations of the benthos micro- to macrofauna, geochemical processes, sampling of bottom water or sedimentology.

The surface area of the box ranges between 200 cm**2 and a quarter of a square meter (50x50 cm = 2500 cm**2); the penetration depth of 0.5 m can be controlled to prevent over-penetration in softer sediments. It allows for large sample sizes which optimizes deploy time and can satisfy sample requests for various investigations.

The box is fixed at the lower end of a large plunger. To deploy the box corer an "A"-frame or a sliding beam with at least 3 m clearance is required. The corer is lowered vertically until it impacts with the seabed. At this point the instrument is triggered by a trip as the main coring stem passes through its frame. The stem has a weight of up to 800 kg to aid penetration. While pulling the corer out of the sediment a spade swings underneath the sample to prevent loss. When hauled back onboard, the spade is under the box.

The recovered sample is completely enclosed after sampling, reducing the loss of finer materials during recovery. Stainless steel doors, kept open during the deployment to reduce any "bow-wave effect" during sampling, are triggered on sampling and remain tightly closed, sealing the sampled water from that of the water column.On recovery, the sample can be processed directly through the large access doors or via the removal of the box completely, together with its cutting blade. A spare box and spade can then be added, ready for an immediate redeployment. The sampling box is made from stainless steel, the cutting blade as well as the corer are galvanised for reduced contamination and corrosion. It can quickly be exchanged and moved by a hand lift for convenient sampling. One side might be unscrewed for documentation and convenient sampling of the profile.

The box corer underwent many alternative development with the advantages of other closing mechanisms, multiple sampling, and modest weight, size and cost (e.g. GOMEX box corer, Multi-Box Corer). The final version of the widely accepted (large) box corer is used since the 80th on research vessels around the world. It originates from the Reineck box corer [Reineck HA (1963) Sedimentgefüge im Bereich der südlichen Nordsee. Abh. Senckenb. Naturforsch. Ges. 505: 1-138] and the USNEL box corer. The device was developed by R. Hessler, Professor of Biological Oceanography, and P.A. Jumars at the Scripps Institute of Oceanography in collaboration with the United States Naval Electronic Laboratory (USNEL) in San Diego [Hessler RR, Jumars PA (1974) Abyssal community analysis from replicate box cores in the central North Pacific. Deep-Sea Research 21:185–209, doi|10.1016/0011-7471(74)90058-8] [Ferris RA, Crezée M (1976) An Improved Reineck Box for Sampling Coarse Sand. Internationale Revue der gesamten Hydrobiologie und Hydrographie, 61(5), 703-705, doi|10.1002/iroh.3510610515] to determine the faunal composition at the abyssal floor [ [http://doi.pangaea.de/10.1594/PANGAEA.692265 Hessler, Robert R; Jumars, Peter A (1974): Abyssal community analysis from replicate box cores in the central North Pacific, supplementary data] ] .A simple predecessor of a device to take sediment samples from vessels which is still in use is the Van Veen grab [Beukema JJ (1974) The efficiency of the Van Veen grab compared with the Reineck box sampler. ICES J. Mar. Sci., 35, 319-327, doi|10.1093/icesjms/35.3.319] .

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