Rivers deposit sediments in different parts of their courses and thus form three major types of landforms which are called constructional landforms such as alluvial fans cones, natural levees and deltas. Depositional Landform # 1. Alluvial Fans and Cones: Alluvial fans (fig. 18.14) and cones (fig. 18.15) due to accumulation of materials are always formed at the base of foothills [...]
Deltas are divided into following six types on the basis of shape and growth: 1. Arcuate Delta 2. Bird-Foot Delta 3. Estuarine Delta 4. Truncated Delta 5. Growing Delta 6. Blocked Delta. Type # 1. Arcuate Delta: Such deltas are like an arc of a circle or a bow and are of lobate form in appearance wherein middle portion has [...]
The following points highlight the top four theories for the development of pediments. The theories are: 1. Lawson's Recession Theory 2. Sheet-Flood Theory of McGee 3. Lateral Erosion Theory 4. Composite Theory. 1. Lawson's Recession Theory: According to A.C. Lawson (1915) pediments are developed because of gradual recession of mountain front caused by weathering and erosion. Due to backwasting of [...]