What defines a delta?

A delta is characterized as a landform that develops at the mouth of a river as it flows into a larger body of water, such as an ocean, sea, or lake. This formation occurs due to the process of sediment deposition, where the river carries sediments collected from upstream and, upon reaching the still waters of the larger body, loses energy and drops its sediment load. Over time, these deposited sediments accumulate, creating a wide, fan-shaped area known as a delta.

The correct definition emphasizes the geographical and hydrological processes involved, distinguishing deltas from other landforms. Understanding this sedimentary process is crucial in river geography, as it illustrates how dynamic river systems alter landscapes and ecosystems.