Four modern shoals on the Louisiana continental shelf are proposed to have formed through transgression, marine reworking, and submergence of Mississippi River deltaic lobes. However, one of these shoals, the St. Bernard Shoals, is dissimilar to the other shoals in morphology and stratigraphy. Understanding the processes that lead to these differences resulted in the development of a wholly new model for subaqueous shoal evolution. The results of this study suggest that the St. Bernard Shoals are transgressive remnants of a near shelf-edge delta lobe that was transgressed and truncated by marine processes after fluvial abandonment. Subsequent to truncation, the shoals formed through subaqueous excavation and reworking of coarse grained sediment contained within underlying distributary channels by hurricane related marine currents. As a result the shoals are bound at their base by a ravinement surface and lie directly upon progradational facies associated with previously unrecognized southern progradation of the La Loutre distributary network.

Every thousand years or so, when the Mississippi River's sediment load lengthened and blocked the River’s route to the Gulf of Mexico, the mother stream changed course completely, finding a shorter route to the sea. Then, it built a new delta, thus spreading the gift of land creation along a wide coastline and creating the bayou region of Louisiana. However, this ancient, natural process was gradually halted by the arrival of man who settled across the River's natural floodplain (delta) and constructed levees and other structures to control the great Mississippi River. Since the 1930s, the Mississippi River Delta Basin and the coast of Louisiana have been literally losing ground. The decline of this environment is now affecting, and will continue to affect, our nation's economy, infrastructure, culture, and safety. Moreover, efforts to fix this problem are not working. My research and this thesis will address the issue of how plans without action have appeased Louisianans while the nation looses vital wetlands daily.