MARKEL, REBECCA K., U.S. Naval Oceanographic Laboratory, Stennis Space Center, MS, and CHRISTOPHER P. CAMERON, University of Southern Mississippi, Hattiesburg, MS

ABSTRACT: Geological Controls and Engineered Structures Relating to Erosion and Land Loss in the Barataria Quadrangle of South-Central Louisiana

Wetlands land loss is an ongoing phenomenon in many coastal areas of the world, but nowhere is this an apparent a problem than in Louisiana's Mississippi River deltaic plain (MRDP). The Barataria Quadrangle experienced one of the highest rates of land loss (634 ac/yr) in the MRDP during 1939-1990, which ranks among the highest rates of land loss for inland areas of this region. Additionally, the Barataria Quadrangle is the only inland area of the MRDP with an accelerated rate of land loss for the period 1983-1990.

Land loss due to natural factors (e.g., clastic sediment decline, erosion, sediment compaction, and regional subsidence) accounts for greater than 15.2% of the total loss (32,346.3 ac) measured by this study. Cultural factors directly impacting land loss in the Barataria Quadrangle are largely confined to the effects of canal dredging, which accounts for 17.5% of the land loss. Indirect impacts of canal dredging (e.g., increased erosion, enhanced sediment compaction, increased saltwater intrusion) account for an additional 67.3%.

Most of the increased land loss during 1983-1990 occurred via erosion of shorelines along bayous, bays, and lakes; and may have been due to changes in area hydrology caused by the cumulative effect of canal dredging.

AAPG Search and Discovery Article #90989©1993 GCAGS and Gulf Coast SEPM 43rd Annual Meeting, Shreveport, Louisiana, October 20-22, 1993.