GENERAL GEOLOGY

Detailed explanation-1: -Detailed Solution. A gorge is a deep channel which is formed by a river that has eroded the earth’s crust over millions of years.

Detailed explanation-2: -The middle course of a river is found on gently sloping land, and is typically identified by its meandering path-the sweeping side to side curves. The middle course has two main features-meanders and ox-bow lakes.

Detailed explanation-3: -As the river makes its way to the middle course, it gains more water and therefore more energy, so material can be carried in suspension and is used to erode the river banks. Lateral erosion starts to widen the river. When a river flows over flatter land it develops large bends called meanders .

Detailed explanation-4: -Detailed Solution. The correct answer is option 1, i.e. Oxbow lakes. The Oxbow lakes formed during the middle course of a river.

Detailed explanation-5: -Erosional landforms of the river include Valleys, Gorges, Potholes, Plunge pools, Incised or Entrenched Meanders, River Terraces etc. Depositional landforms of the river include Alluvial Fans, Deltas, Flood Plains, Natural Levees, Meanders, Oxbow lakes, Braided Channels etc.