Mr Paul Donaldson1, Dr Douglas Bergersen2, Dr Matthew Barnes3, Mr Conor Jones3
1BMT, Newcastle, Australia, 2Acoustic Imaging, Cooroy, Australia, 3BMT, Brisbane, Australia
Solutions for coastal management problems often require information on conditions below the ground, such as the geological/geotechnical characteristics of the subsurface, or the location, depth and shape of buried infrastructure. Environmental geophysical methods have the potential to help in this regard, and especially so where traditional investigative techniques are either too expensive, destructive or simply unworkable. Such data provide invaluable assistance for focusing sampling programs for example, that can potentially result in considerable cost savings. For this reason, shallow geophysical methods such as ground penetrating radar are increasingly used as a coastal management tool in onshore environments, including in the upper beachface, dune and backbeach settings. Similarly, marine seismic and sub-bottom profiling methods are becoming an important survey tool in estuarine and marine environments, and especially so when coupled with acoustic swath mapping of the seabed bathymetry and backscatter properties. Broad expertise in geophysics is required to use these technologies, in addition to specialist training and experience in each method.
At a practical level, coastal managers generally have limited knowledge of the range of geophysical techniques and potential applications available to coastal science and engineering. This paper provides an introduction to coastal practitioners on the various uses, advantages and limitations of geophysics in the coastal and marine environment. Applications include, for example, geological and geomorphological surveys to improve understanding of coastal/marine conditions and processes; site characterisation of geotechnical properties to inform erosion hazard assessments and design of coastal engineering structures (e.g., seawalls); and surveys of buried coastal or marine infrastructure for asset management purposes. This paper examines opportunities to apply environmental geophysics to coastal and marine management problems through the lens of case study projects.
Paul is a Senior Coastal Scientist with BMT in Newcastle NSW, with industry and research experience in coastal geomorphology, environmental geophysics and coastal management.