Bring out the causes for more frequent landslides in the Himalayas than in the Western Ghats.
Introduction
The Himalayas experience significantly more frequent landslides than the Western Ghats due to a confluence of distinct geological, topographical, climatic, and anthropogenic factors.
Body
Geological and Tectonic Factors
- Himalayas: Young, tectonically active fold mountains; unstable, fractured rocks; high seismicity from plate collision.
- Western Ghats: Older, stable block mountains; minimal tectonic activity.
Topographical and Lithological Factors
- Himalayas: Extremely steep slopes, high relief, deep valleys; fragile, unconsolidated sediments, highly jointed rocks.
- Western Ghats: Gentler slopes, resistant igneous and metamorphic rocks.
Climatic and Hydrological Factors
- Himalayas: Intense rainfall, cloudbursts, snow/glacial melt causing high water saturation and pore pressure.
- Western Ghats: Heavy monsoon rainfall, but less extreme hydrological events.
Anthropogenic Factors and Seismic Activity
- Himalayas: High seismic activity triggers landslides; unplanned infrastructure, deforestation, tourism destabilize slopes.
- Western Ghats: Seismically stable; comparatively less intense human pressure.
Conclusion
This unique interplay of active tectonics, rugged terrain, fragile geology, extreme climate, and human interventions makes the Himalayas far more susceptible to landslides.
153 words · target ~150
The directive requires identifying and explaining the specific causes that lead to a higher frequency of landslides in the Himalayas compared to the Western Ghats.
Suggested structure
Introduction: Acknowledging the premise of higher landslide frequency in the Himalayas
Geological and Tectonic Factors (Himalayas vs. Western Ghats)
Topographical and Lithological Factors (Himalayas vs. Western Ghats)
Climatic and Hydrological Factors (Himalayas vs. Western Ghats)
Anthropogenic Factors and Seismic Activity (Himalayas vs. Western Ghats)
Conclusion: Summarizing the key differentiating causes
Key points
Himalayas are young, tectonically active fold mountains formed by plate collision, leading to unstable, fractured, and highly seismic zones, unlike the older, stable block mountains of the Western Ghats.
The Himalayas feature extremely steep slopes, high relief, and deep river valleys, which are inherently more prone to mass wasting compared to the comparatively gentler slopes and lower relief of the Western Ghats.
Himalayan lithology consists of fragile, unconsolidated sediments, highly jointed, and weathered rocks, making them less resistant to erosion and more susceptible to failure than the more resistant igneous and metamorphic rocks of the Western Ghats.
The Himalayas experience intense rainfall (including cloudbursts), significant snowmelt, and glacial melt, leading to high water saturation, increased pore pressure, and greater erosional power, which is generally more extreme than the heavy but primarily monsoon-driven rainfall in the Western Ghats.
High seismic activity in the Himalayas frequently triggers landslides, whereas the Western Ghats lie in a relatively stable seismic zone.
Extensive, often unplanned, infrastructure development (roads, dams), deforestation, and tourism in the Himalayas significantly destabilize slopes, exacerbating natural vulnerabilities more intensely than similar issues in parts of the Western Ghats.
Common mistakes
Failing to explicitly compare and contrast the two regions, instead listing general causes of landslides.
Overlooking the fundamental geological and tectonic differences (age, stability, plate tectonics) between the Himalayas and Western Ghats.
Not adequately emphasizing the role of seismic activity and extreme hydrological events (like cloudbursts, snowmelt) specific to the Himalayas.
Providing a generic description of landslides without linking causes directly to the higher frequency in the Himalayas.
Difficulty: Medium — The question requires specific comparative knowledge of the physiographic, geological, climatic, and anthropogenic factors of two distinct Indian regions. It demands analytical comparison rather than mere description, which elevates it beyond an 'easy' question, but the concepts are fundamental to Indian geography, making it not 'hard'.