GPR Surveying of Carbonate Beach Strandplain Deposits in the Bahamas

The Bahamas is an ideal location for studying the calcium carbonate sedimentation of Holocene strandplains in relation to seaward progradation. We use ground-penetrating radar (GPR) to image and interpret the fine-scale stratigraphy of three carbonate strandplains on Crooked Island, The Bahamas. GPR has been extensively used to analyse the interiors of clastic strandplain deposits worldwide, while tropical carbonate settings have received less attention. Due to the lack of outcrops in our study area on Crooked Island, we validate the interpretation of the 2D profiles by comparing them with a 3D GPR data volume collected adjacent to and over a Pleistocene aeolianite outcrop on San Salvador Island, where porosity layering can be directly observed. Data processing employed state-of-the-art techniques adapted from the petroleum industry to enhance the visualisation of reflection amplitude on the GPR images. Our data support a model in which the progradation of carbonate sediment preserved in strandplains was deposited through a combination of storm processes and gradual sediment progradation.