Mitigating Dredging Risks Using Enhanced Geophysical Methods - The Aquares Resistivity Method

Abstract

Summary The development of a new or existing port involving features such as quaywalls, turning basins, access channels and reclamation areas generally is significantly affected by local geological conditions. In general these represent a high risk factor to the construction project if they are not well described. When appropriate geological ground models are available the design of the construction can profit from it, reducing dredging and construction costs. The geological model forms the basis of quantities, design and risk management. The mitigation of geological risks in ports and marine construction can be realised by including enhanced geophysical methods in the early project state. Enhanced geophysical methods are defined as high quality geophysical methods capable of producing accurate 4D digital ground models showing sediment and rock depths and thicknesses as well as rock and sediment qualities. The Aquares resistivity method is an enhanced geophysical method. This paper explains the principles of this method and shows how it has been used in the past as an essential and highly successful tool to generate digital 4D ground models used for mitigating geological risks in ports and marine construction projects. Inappropriate practices in current site investigation procedures are described to as ways to overcome them.