Earthquakes are caused by:

Question

Earthquakes are caused by:

1. A. Denudation
2. B. Earth's Rotation
3. C. Movement of Tectonic Plates (Correct answer)
4. D. Earth's Revolution

Correct Answer

Option C — Movement of Tectonic Plates

Detailed Solution & Explanation

The correct answer is Movement of Tectonic Plates.

Key Points

• Earthquakes are caused chiefly by the movement of tectonic plates: stress builds along plate margins and faults, and is released suddenly as seismic waves.
• Denudation is the wearing away of the land surface, and the earth's rotation and revolution have no role in generating earthquakes.

Additional Information

• The point of origin underground is the focus (hypocentre); the point vertically above it on the surface is the epicentre.
• Seismic waves come in three kinds: P (primary, fastest, travel through solids and liquids), S (secondary, solids only) and L (surface, most destructive).
• Magnitude is measured on the Richter scale and intensity on the Mercalli scale; India's seismic zoning runs from Zone II to Zone V, with the Himalayan belt and Kashmir in the highest categories.