Answer:
Valley defined as an elongated region or strip of land that is lower than surrounding areas; most often made by the erosive action of a river or glacier. Also see U-Shaped Valleys and V-Shaped Valleys.
Various uses of valleys can be utilized:
1. Exploration for petroleum and groundwater.
2. Always valleys are rich in high quality sand that can be used for hardware and chips for computation purposes.
3. Often valleys are rich regions in minerals and commercial materials.
4. Valleys are attractive tracts for immigration because of the superficial plants for their animals.
Dr. Waleed Shukry El Diasty,
Mansoura - EGYPT