Q4. हिमालय क्षेत्र तथा पश्चिमी घाटों में भू-स्खलनों के विभिन्न कारणों का अंतर स्पष्ट कीजिए । (150 शब्दों में उत्तर दीजिए)
Q4. Differentiate the causes of landslides in the Himalayan region and Western Ghats. (150 words) 10 Marks
Landslides are the mass movement of soil, rocks or debris from a mountain slope under the influence of gravity. Landslides are caused by geology, morphology and human activity.
The causes of landslides in the Himalayan region and Western Ghats can be discussed as:
- Plate Tectonics: Himalayan region is tectonically active as the Indian Plate is moving towards the north at the rate of 5 cm/year. This movement leads to collision of the Indian Plate with the Eurasian Plate, that causes frequent tremor and isostatic imbalances. But the Western Ghats are tectonically more stable as compared to the Himalaya.
- Exogenetic forces: The Himalayan region is the source of many rapid flowing rivers such as the Ganges, the Indus, the Brahmaputra etc. These running rivers cause a large scale erosion of mountainous region which also a cause of landslide. In the Western Ghats, perennial rivers are rare.
- Rock structure: The Himalayan region is composed of a sedimentary rocks which are more prone to denudation and erosion as compared to the other rocks. While, the major part of Western Ghats is composed of a basalt rocks which shows great resistance to erosion and denudation.
- Human interference: The development activities such as construction of roadways and railways, haphazard urbanization ignoring the slope aspects of the landscape etc aggravated the occurrence of landslide. As the Western Ghats is notified as Biodiversity Hotspot, the human interference is less as compared to the Himalayan region and less prone to landslides.