Sedimentary rocks are formed on or near the Earth's surface, in contrast to metamorphic and igneous rocks, which are formed deep within the Earth. The most important geological processes that lead to the creation of sedimentary rocks are erosion,weathering,dissolution,precipitation and lithification.
The Mississippi delta is located on the northwest part of the state of Mississippi and is the most southern place on earth and is 7,000 square miles of alluvial flood plains are created by the regular flooding of the Mississippi and Yazoo rivers for thousands of years.
The river deposited sand, and clay, silt along its banks and in adjacent basins, and is shaped of a bird's foot reflecting the dominance of the river over the hydrological and processes. As the river changes its course the natural flow of freshwater and sediments change as well.