Our national parks contain diverse coastal environments: high-energy rocky shorelines of Acadia National Park in Maine, quiet lagoons within War in the Pacific National Historic Park in Guam, and the white sandy beaches of Gulf Islands National Seashore in Mississippi and Florida.
A variety of factors—including wave energy, tidal range, sediment supply, sediment type, continental-shelf slope and width, and past geologic history (e.g., glaciation, volcanism, and plate movement)—characterize coastal environments.
The coastal zone is one of the most dynamic regions on earth. Think of it, 70% of our planet is covered in water possessing enormous energy! Shorelines can be generally divided into two types, high-relief erosional shorelines and low-relief depositional shorelines.
- Beach Ridges
Beach ridges are wave deposited sand ridges running parallel to shoreline.
- Wave-Cut Scarps
A wave-cut scarp is a steep bank created by wave erosion.
- Marine Terraces
A marine terrace is a raised beach or 'perched coastline' that has been raised out of the reach of wave activity.