Mountains and Plateau
Mountains are such highlands whose slopes are steep and the peaks are pointed. Generally, the mountains are more than 1000 mts high. The mountains whose height is less than 1000 mts, are called hills. The highest point of a mountain or a hill is called its peak. A mountain range is a system of mountains and hills having several ridges, peaks, summits and valleys, formed in a particular period and spread in a narrow belt.
Classification of Mountains
- Folded Mountains: These Mountains are the results of compressive forces, triggered by the endogenetic forces. When the rocks on (he surface of the earth are folded due to the forces generated within the earth, the resultant Himalaya Ural, Rockies, Andes, Atlas etc. examples of folded mountains.
- Block Mountains: These Mountains originate due to the forces of tension leading to the formation of rift valleys. These are also know as fault Block Mountains, as they are the result of faulting. Sierra Nevada mountain of California, USA, Vosages and Black Forest mountains of Europe.
- Accumulated Mountains: These mountain are formed due to accumulation of lava other ejected materials in the proccess of vulcanism. Fujiyama of Japan, Cotopaxi of Equador are its examples.
- Relict Mountains: When orginal mountains are eroded by the agents of gradation, they become relict mountains. Vindhyas, Aravallis, Satpura, Eastern Ghats, Western Ghats, Parasnath etc. are relict mountains.
A plateau may be defined as that upland which has at least one side of very steep slope standing well above the neighbouring surface and whose upper part is extensive and almost flat.
Classification of Plateau
- Intermontane Plateau: These Plateaus are surrounded by hills and mountains from all sides. For Example Tibetan plateau, Columbian plateau.
- Piedmont Plateau: Which is surrounded by-mountain range on one side and by plain or ocean on the other side. For Example Appalachian Mountains (USA) and Patagonian plateau of South America.
- Dome Shaped Plateau: These Plateaus are formed when the landmass is uplifted in such a manner that the middle portion is raised and the sides are rounded. Chhotanagpur plateau of Jharkhand, Ozark Plateau (USA).
- Continental Plateau: These are very extensive Plateau and surrounded by oceanic coasts or plains. These are also called Shield. For Example Siberian shield.
- Volcanic Plateau: These Plateau are formed due to accumulation of thick layers of bassltic laves. Deccan plateau of India and Columbian plateau of USA are the best example of this type.
|Alaska / Yukon