Drilling cores on the sea floor with the remote-controlled sea-floor drilling rig MeBo

Abstract

Sampling of the upper 50 to 200 m of the sea floor to address questions relating to marine mineral resources and gas hydrates, for geotechnical research in areas of planned offshore installations, to study slope stability, and to investigate past climate fluctuations, to name just a few examples, is becoming increasingly important both in shallow waters and in the deep sea. As a rule, the use of drilling ships for this kind of drilling is inefficient because before the first core can be taken a drill string has to be assembled extending from the ship to the sea floor. Furthermore, movement of the ship due to wave motion disturbs the drilling process and often results in poor core quality, especially in the upper layers of the sea floor. For these reasons, the MeBo drilling rig, which is lowered to the sea floor and operated remotely from the ship to drill up to 80 m into the sea floor, was developed at the MARUM Research Center for Marine Environmental Sciences at Bremen University. The complete system, comprising the drill rig, winch, control station, and the launch and recovery system, is transported in six containers and can be deployed worldwide from German and international research ships. It was the first remote-controlled deep sea drill rig that uses a wireline coring technique. Based on the experiences with the MeBo a rig is now being built that will be able to drill to a depth of 200 m.

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Identifiers

DOI

10.5194/gid-3-347-2013

Journal

Unknown journal

Year

2013