Sedimentology by Satellite: Space Age Approach to the Coastal Zone

Larry J. Doyle, Gail McGarry

Although sedimentology has developed an understanding of the general dynamics of coastal systems through traditional sampling and repetitive beach profiling, extreme variability and size of the systems have precluded their quantitative assessment, especially of their submarine portions. Satellites such as LANDSAT (EOSAT) and SPOT, with a variety of spectral configurations, combined with computer interpretive systems will allow us to synoptically evaluate coastal systems at relatively short intervals. Resolution of satellite images measured in meters dictates concentration on large-scale changes and fluxes. In areas of relatively clear water, such as the Mediterranean Sea or the eastern Gulf of Mexico, some satellite spectra will allow us to map below the sea surface and h nce determine how the innermost shelf changes with time.

To illustrate these points, we studied the barrier island system of the central west Florida coastline (USA) before and after the 1985 hurricane season. Two major storms impacted this region during that period. By computer overlaying before and after images, we were able to map changes in the barrier islands and to quantify acreage gained and lost. We were also able to detect and map changes in the submarine portions of the system, especially in the ebb and flood tidal deltas associated with inlets. The third dimension can be added by surveying the submarine features with high-resolution geophysics. Applications of this kind hold the promise of a new era in investigating beach/barrier islands and their relationship with the inner continental shelf.

AAPG Search and Discovery Article #91032©1988 Mediterranean Basins Conference and Exhibition, Nice, France, 25-28 September 1988.