Which mechanism creates natural levees bordering a mature alluvial river?

💡 Explanation

When a river overtops its banks during floods, the flow velocity decreases abruptly because of increased surface area, leading to sediment deposition because the flow can no longer carry as much sediment. Therefore sediment deposition forms levees, rather than flocculation, weathering or icelanding that involve different specific compositions or temperature thresholds.

• Which outcome occurs when heavy rainfall saturates tropical laterite soil?
• Which phenomenon causes the Coriolis effect on major ocean currents near continental coastlines?
• Which mechanism reduces soil fertility when prolonged floodplain inundation occurs on alluvial plains used for agriculture?
• Which outcome arises when weakened trade winds reduce upwelling off South America during an El Niño event?
• Which outcome increases proximal fault stress when stick-slip behavior occurs?
• Which process establishes distinct stratification layers within a dimictic lake?