Geologic framework, evolution, and sediment resources for restoration of the Louisiana Coastal Zone

The Louisiana Coastal Zone along the north-central Gulf of Mexico represents one of America's most important coastal ecosystems in terms of natural resources, human infrastructure, and cultural heritage. This zone also has the highest rates of coastal erosion and wetland loss in the nation because of a complex combination of natural processes and anthropogenic activities during the past century. In response to the dramatic land loss, regional-scale restoration plans are being developed through a partnership of federal and state agencies. One objective is to maintain the barrier island and tidal inlet systems, thereby reducing the impact of storm surge and interior wetland loss. Proposed shore line restoration work relies primarily upon the use of large volumes of sand-rich sediment for shoreline stabilization and the implementation of the shoreline projects. Although sand-rich sediment is required for the Louisiana restoration projects, it is of limited availability within the generally clay to silt-rich, shallow strata of the Louisiana Coastal Zone. Locating volumetrically significant quantities of sand-rich sediment presents a challenge and requires detailed field investigations using direct sampling and geophysical sensing methods. Consequently, there is a fundamental need to thoroughly understand and map the distribution and textural character {e.g., sandiness) of sediment resources within the Coastal Zone for the most cost-effective design and completion of restoration projects.