THE INTERNAL STRUCTURE OF VEGETATED COASTAL SAND DUNES, SABLE-ISLAND,NOVA-SCOTIA

New data and a comprehensive analysis of stratification and sedimentat ion in the complex vegetated dunes of Sable Island, Nova Scotia are pr esented. The internal structures of the dunes are analyzed using a des criptive legend, from an earlier paper (Byrne and McCann, 1990), which was based on three elements-grain size, stratification, and the natur e of plant remains. Analysis of the stratification and sedimentary cha racter of the dunes at three sites along the north shore and at ten si tes in the interior of the Island involved modifications to the origin al descriptive legend and a more comprehensive listing of the modes of deposition. The sites discussed here represent the evidence that was available during the field season (summer 1987 and 1988) without exten sive excavations and disturbance of the terrain. Genetic interpretatio n of the complete data set indicates that the main dunes of Sable Isla nd fall into two categories: (1) Primary dunes, which have developed i n situ, through several phases of sedimentation at the back of the nor th beach (three sites). (2) Secondary dunes, including various remnant forms, which result from the passage of migrational dunes, in the int erior of the island (ten sites). Three types of secondary dunes are de fined. These dune types are summarized in a map and as a block diagram that can be used to document the development of the dunes and dune sy stems on the island.