River Depositional Landforms

From steep mountains to the open sea 🌊, a river’s journey is also a story of deposition.

As velocity decreases, the river loses energy and begins to drop its load—sorting sediments from gravel → sand → silt → clay along its course.

🔹 Upper course: Coarse material forms alluvial fans at the base of mountains

🔹 Middle course: Meanders develop—erosion on outer bends (cut banks) and deposition on inner bends (point bars); sometimes channels split into a braided river

🔹 Lower course: Fine sediments build wide floodplains and natural levees during floods

🔹 At the mouth: Deposition creates a delta with distributaries as the river enters slower-moving water

🔹 Over time: Meander cut-off forms a crescent-shaped oxbow lake.

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