Beach etching and shore platforms

Etch forms are widely recognised in continental landscapes, but little attention has been given to the etch factor in the coastal context. Evidence, mainly from South Australia and the Iberian Peninsula, is cited of weathering fronts fortuitously located within the tidal zone and exposed by the stripping of a regolith by waves. In addition, the possible effects of beach etching or weathering by waters retained by beach sediments are discussed. Such weathering is difficult to prove in detail, but circumstantial evidence from South Australian sites suggests it contributes to the development of shore platforms, as well as to cliff-foot depressions and an assemblage of minor forms, such as basins, rock doughnuts, and fonts. The zonation of basins and gutters noted on some coasts may also, and in part, reflect beach etching.