Geotechnical Characterisation of Submarine Slope Movements, Example from the Area off the Nice Airport (SE France)

In order to present the geotechnical approaches and tools developed and deployed in IFREMER, light is shed on the shelf and upper slope off the Nice airport. The complex problem of submarine mass movements is split into two distinct aspects that are the mechanical behaviour of sediments and the movement stages. It is hence shown that the area off the Nice airport remains predisposed to failure due to fresh water infiltration and gas occurrence in the sediments. The steep continental slope is recognised as a factor predisposing both failure and subsequently large and rapid movements of sediments. Given the high probability for a 30-m thick slide to occur due to the occurrence of shear zones, conclusions point toward the need to deploy an array of sensors for the monitoring of changes in pore pressures and potential pre-failure movements.