A silt deposit is a sedimentary deposit composed of fine-grained particles, such as clay, silt, and sand. The two most common types of silt deposits are loess and DELTA deposits. Loess is a type of silt deposit that is formed by the accumulation of wind-blown dust and is found in areas with dry climates. DELTA deposits are formed when rivers deposit sediment at their mouths, creating a triangular-shaped landform.