Alluvial Fan

An alluvial fan is a geological formation that occurs when a river or stream flows out of a narrow mountain area and spreads out over flatter land. As the water slows down, it drops the sediment it was carrying, creating a fan-shaped deposit of soil and debris. This shape is wider at the bottom and narrower at the top, resembling an open fan. Alluvial fans are important because they can create fertile land for agriculture and provide valuable water resources, but they can also be prone to flooding and erosion.