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School of Applied Sciences, University of Wolverhampton, Wulfruna Street, Wolverhampton WV1 1SB, UK
Acquisition of high resolution data regarding the stratigraphy and internal structure of coastal sedimentary sequences is becoming increasingly important in many sedimentological, geomorphological and geoarchaeological studies. Such information is usually obtained from the logging of field exposures, shallow trenches and cores. However, ground-penetrating radar (GPR), a relatively new and rapidly developing non-invasive geophysical technique, may also aid such investigations in certain coastal settings, providing additional, complimentary and often unique data sets. The technique is based on the transmission, reflection and reception of high frequency electromagnetic (radar) waves, with reflections occurring in the subsurface due to the varying electrical properties of the sediments. Such reflections can occur due the presence of primary sedimentary structures, lithological/material changes or water content changes. Examples presented from the UK indicate that the technique can accurately delineate the stratigraphy and internal sedimentary structure of coastal barriers, spits and strandplains, both above and below a fresh groundwater table. Sand and/or gravel-dominated beach-dune systems on moderate to high wave energy, macrotidal coasts appear to provide optimum settings for GPR deployment. In addition, the technique also has the potential to locate, map and provide stratigraphic context for a wide range of archaeological features that are commonly found in such coastal environments.
