How did the Mississippi River delta form?
-As the Mississippi River enters the Gulf of Mexico, its velocity decreases and it begins to drop its sediment load.
-As sea level has risen since the end of the last Ice Age, wave action along the Gulf Coast has eroded the mainland, leaving behind a lobe-shaped landmass.
-When the Mississippi River floods its banks, sand grains settle out just beyond the river's normal banks to form a natural ridge.
-After Pangea broke apart, the North American plate has continued on a northward course, leaving debris on the trailing edge.
-Dams and locks trap sediment. To keep the Mississippi River clear for navigation, sediment is dredged and dumped along the shoreline and forms a delta.