Late Neogene Mass Transport Deposits of the West Nile Delta, Egypt

Bryn J. Austin and the BP Geohazard Assessment Team
BP, Sunbury on Thames, United Kingdom

The West Nile delta is characterised by a recurrent, episodic sedimentary Late Neogene history during which phases of deposition alternate with mass movements and sediment transfers to deep water. The deposition mechanisms exhibit a complex history with the migration of cut and fill sequences, channel-levee units, and avulsions in response to variable slope, tectonic history, faulting and sediment yield. The landslides vary in scale from regional (c. 20km x 100km x 100m) to medium (c. 5-10km x 20-50km x 20-50m) to small (1-2km x 2-5km x 10-20m) as well as numerous local surface failures and debris flows. They are being explored in some detail by detailed geomorphological mapping using a variety of 3D and much higher resolution 2D seismic data sets. Careful attention to the integration of multi-disciplinary methods ensures that the complex geometries are fully understood within a total earth science framework. The resulting seismically driven shallow stratigraphical model is being verified by careful dating and a comprehensive geotechnical sampling and testing framework. The thorough assessment will form the basis for risk assessment, geotechnical slope stability modelling for sub sea development well and facilities planning