भूकंप का मुख्य कारण है:

Question

भूकंप का मुख्य कारण है:

1. A. क्षरण
2. B. निरावरण
3. C. विवर्तनिक बल (Correct answer)
4. D. अपक्षयण

Correct Answer

Option C — विवर्तनिक बल

Detailed Solution & Explanation

The correct answer is विवर्तनिक बल (tectonic forces).

Key Points

• Most earthquakes are caused by the sudden release of accumulated stress along faults as tectonic plates move against one another.
• The point of origin inside the earth is the focus/hypocentre; the point vertically above it on the surface is the epicentre.

Additional Information

• Magnitude is measured on the Richter scale; intensity of damage on the Mercalli scale. Instruments: seismograph.
• Himachal Pradesh lies largely in seismic zones IV and V, making it highly earthquake-prone — the Kangra earthquake of 4 April 1905 killed over 20,000 people.
• Erosion and weathering shape landforms slowly, but do not cause earthquakes.