Q. Differentiate the causes of landslides in the Himalayan region and Western Ghats.

Model Answer: 

Landslides in the Himalayan Region and Western Ghats: A Comparison

Landslides, a common geohazard in mountainous regions, occur frequently in both the Himalayas and Western Ghats. However, their causes differ significantly due to distinct geological, climatic, and anthropogenic factors.

Causes of Landslides in the Himalayan Region

• Geological factors:
– Young, tectonically active mountains prone to instability
– Frequent seismic activity (e.g., 2015 Nepal earthquake)
– Presence of weak and fractured rock structures
• Climatic factors:
– Heavy rainfall during monsoons
– Glacial melt due to climate change (e.g., Kedarnath disaster, 2013)
• Anthropogenic factors:
– Deforestation leading to soil erosion
– Unplanned construction activities
– Extensive road cutting on steep slopes (e.g., Char Dham project)

Causes of Landslides in the Western Ghats

• Geological factors:
– Ancient, highly weathered rock formations
– Deep soil profiles susceptible to saturation
• Climatic factors:
– Intense monsoon rainfall (e.g., Kerala floods, 2018)
– High humidity accelerating rock weathering
• Anthropogenic factors:
– Extensive mining activities (e.g., Goa iron ore mines)
– Changes in land use patterns
– Deforestation and agricultural practices on steep slopes

Differentiating Landslide Causes: Himalayas vs Western Ghats

1. Geological setting: Himalayas are young, unstable mountains, while Western Ghats are old, weathered formations.
2. Trigger mechanisms: Seismic activity plays a significant role in the Himalayas, whereas rainfall is the primary trigger in Western Ghats.
3. Scale and frequency: Himalayan landslides are often larger and more frequent due to the region’s high seismicity and ongoing tectonic activity.

Conclusion

Understanding these regional differences is crucial for developing effective, location-specific landslide mitigation and management strategies.