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of marine and coastal environments affected by a dangerous hydrodynamic climate and in the vicinity of offshore structures. The initiation and ongoing seabed activity were detected via changes in the deceleration gradients and in sediment resistance. Estimating an equivalent of QSBC confrmed that such changes in gradients were not related to artifacts of the nonlinear backcoupling between recorded deceleration and decreasing penetration velocity. Furthermore, areas of sediment erosion and sediment deposition were mapped, and sediment accumulation was quantifed with a resolution of about 1 centimeter. The instrument covered up to 50 deployment positions within one hour, depending on vessel navigability. Nevertheless, a number of questions and uncertainties remain. Regarding the device, it would be desirable to increase penetration depth into sandy sediments and decrease form and tether drag in water depths greater than 100 meters. Hull modifcations and a more fexible weight system are under development. With regard to data processing, future work should be directed toward correlations between deceleration profles and in-situ density and shear strength. Such methods are developed for cone penetration test lance systems but are still not well established for small-scale penetrometers. This is especially the case for sandy sediments, and loosely packed surface layers. The estimate of an equivalent of QSBC accounted for changes in penetration surface area and penetration velocity, but the assessment of properties such as in-situ density and shear strength would be more directly applicable to the investigation of sediment remobilization. More controlled experiments will be the next step to target this issue. Recordings from Nimrod���s pressure transducer were of limited use for studying the development of pore pressure in the active layer. The pore pressure in the active, loose top layer is affected by the penetration process and will not recover to ambient pore pressure states within a reasonable time frame. The penetrometer pressure transducer had often already passed the active layer and penetrated into the stable substratum when the penetrometer came to a stop. For monitoring pore pressure development with ongoing sediment remobilization, experiments using a vertical array of pressure transducers for long-term observations (e.g., several tidal cycles) at chosen positions are a work in progress. Generally, the geotechnical investigation of sediment remobilization processes in situ and in the laboratory, is an important complement to the ongoing research on sediment dynamics and will lead to improved assessment of seafoor and offshore structure stability and more accurate models of geomorphologic development. Acknowledgments The authors would like to thank the German Research Foundation for funding via MARUM, Bremen International Graduate School for Marine Sciences (GLOMAR) and Integrated Coastal Zone and Shelf-Sea Research (INTERCOAST) to the University of Bremen. Presented results in this article were also supported by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (via the German Federal Maritime and Hydrographic Agency), the German Academic Exchange Service, the Coastal Marine Group of the University of Waikato, the National Institute of Water and Atmospheric Research, ASR Ltd., OCEL Ltd. (Christchurch, New Zealand), Port of Tauranga, Lyttelton Port of Christchurch and the ��LEMO project by the Fondation pour l�����tude des Eaux du L��man. The authors are deeply indebted for technical support to MARUM���s Christian Zoellner, Matthias Lange and Hendrik Hanf, as well as Craig Lake from Dalhousie University. Furthermore, this article beneftted from review by Alex E. Hay of Dalhousie University. n Nina Stark, now a postdoctoral fellow at Dalhousie University, received her Ph.D. from the marine geotechnics working group at MARUM, University of Bremen, where she developed the Nimrod. She accomplished her master���s thesis at the University of M��nster, in collaboration with the Naval Research Institute for Geophysics and Water Acoustics. Achim Kopf is a full professor for marine geotechnics at MARUM, University of Bremen. His research and developments focus on sediment physical behavior in the geotechnical laboratory, by in-situ measurements and from borehole observatories. www.sea-technology.com FEBRUARY 2013 / st 59