fließkegelfluss

Fließkegelfluss refers to the depositional landform created by the accumulation of sediment carried by a stream as it emerges from a confined channel into a broader, unconfined area. This process is common in arid and semi-arid regions where intermittent streams, often called ephemeral streams or wadis, flow from mountains or hills onto plains or valleys. As the stream's velocity decreases due to the loss of confinement and increased surface area, it loses its capacity to transport its sediment load. Consequently, the sediment, primarily gravel, sand, and silt, is deposited in a fan-shaped or cone-shaped pattern, with the apex of the fan at the point where the stream exits the confined area.

These landforms are known by various names globally, including alluvial fans, debris fans, or simply cones. The size and shape of a fließkegelfluss are influenced by factors such as the volume of sediment supplied, the discharge of the stream, and the topography of the receiving basin. Larger streams with higher sediment loads and steeper gradients tend to produce larger and steeper fans. The surface of a fließkegelfluss is typically characterized by distributary channels, which are smaller channels that spread out across the fan, further distributing the water and sediment. Over time, multiple fließkegelflüsse can coalesce to form extensive piedmont plains. They can also be significant sources of groundwater recharge and can host unique ecological communities adapted to the coarse, well-drained soils.