A delta forms at the mouth of the Mississippi River due to sediment deposits.

Over time, material carried by the river accumulates to form a delta near the mouth of the Mississippi River. Sand, silt, and clay are deposited by the river as it slows and expands into the Gulf of Mexico, creating this landform. One of the most important is the Mississippi River Delta, which contributes to the region's great biodiversity and fertile soils that sustain both agriculture and animals.