Hurricane Impacts on Louisiana's Barrier Islands (1985): Geomorphic Changes in the Isles Dernieres, 1984-85

摘要

The impacts of 1985 hurricanes Danny, Elena, and Juan on the geomorphology of the Isles Dernieres barrier island arc (off the Louisiana coast) were assessed by means of aerial videotape mapping. A coastal geomorphic classification system was developed to map the differences between pre-storm and post-storm conditions. The Isles Dernieres coast is low-profile, transgressive, and composed primarily of washover flats and higher dunes and washover terraces. The hurricanes reduced the island's morphology to washover flats, intertidal flats, and other low-relief landforms. The rate of shoreline change and sediment supply control landform development on the Isles Dernieres. The lower-relief landforms are more sensitive to storm impacts. Vegetation is important in reducing the effects of hurricanes. A barrier island restoration project at one site reduced erosion and prevented breaching.