SHRIMP: an investigation tool for pipeline and cable burial

Pipelines and cables are more and more usually buried into the seabed. Several techniques are available (ploughing, trenching, jetting or dredging), but the choice of the appropriate tool and the estimation of the work advancement speed need precise information concerning the seafloor characteristics. Conventional methods including soundings and reflection seismics are not appropriate for survey before burial. A new tool based on refraction seismic on the seabed has been developed. The real time processing gives the P-waves velocities and the thickness of the different layers inside the sediment. The depth of investigation into the seafloor is between 3 and 10 metres. The accuracy in layer thickness is about 25 centimetres