The investigation and characterisation of the Chalk and overlying Thames deposits at Tilbury, Essex, UK

This paper describes the large scale spatial distribution of the Chalk in the Tilbury area of the River Thames in Essex. This is based on a number of historical and recent ground investigations from over-water and onshore sites including the Port of Tilbury, the former Tilbury power station and a proposed Thames Tideway jetty site east of Tilbury. The chalk in the area is primarily the Seaford Chalk Formation, and in the Tilbury area of the Thames the chalk is overlain by extensive deposits of Thames Alluvium comprising soft and compressible organic clays, peats and silts which are directly underlain by River Terrace Deposits. This paper describes the various ground investigations and methods used and the relationship of the chalk and the overlying superficial deposits, including discussion of the weathering profile and geotechnical properties of the chalk. The interpretation used HoleBASE SI to geographically assess the spatial distribution of the chalk in the Tilbury area.