A depositional landform occurring where streams emerge a mountain area in a desert is?

The depositional landform occurring where streams emerge from a mountain area in a desert is an alluvial fan. An alluvial fan is a cone-shaped deposit of sediment that forms where a fast-moving stream or river meets a plain or valley. The sediment, which is usually composed of sand, gravel, and other debris, is carried downstream by the flowing water and eventually spreads out over a wide area when the water slows down. In a desert setting, these alluvial fans can be quite large and are an important source of water and fertile soil for plants and animals that live in the region.