The process of sedimentation has helped shape the fertile soils of the Interior Plains.

The Interior Plain's lush, fertile soils are largely the result of sedimentation. Layers of minerals and biological elements formed throughout the area over thousands of years by sediments from rivers, lakes, and the ancient Western Interior Seaway. Decomposing plant matter and nutrient-rich sediments left by the seaway's retreat created extremely fertile soils. Because they make it possible to grow crops like wheat, canola, and barley, these fertile areas are essential to agriculture. The Interior Plains are one of North America's most important agricultural regions, crucial for the production of food, thanks to the interaction of sedimentation and organic matter.