Daily Quiz- 182

Earthquakes, plate tectonics and volcanoes

Chandigarh, Updated At : 07:23 PM Aug 07, 2025 IST

1. Which of the following seismic waves do not pass through liquids?

A. Primary waves (P-waves)

B. Surface waves

C. Secondary waves (S-waves)

D. Rayleigh waves

2. Which layer of the Earth is most responsible for the movement of tectonic plates?

A. Lithosphere

B. Asthenosphere

C. Mantle

D. Outer Core

3. What is the main difference between Richter Scale and Moment Magnitude Scale (Mw)?

A. Richter is used for deep-focus, Mw for surface quakes

B. Richter measures energy; Mw does not

C. Richter is outdated and less accurate for large quakes

D. Mw is used only for volcanic earthquakes

4. What explains the absence of volcanoes along the Himalayan range despite it being a collision zone?

A. High seismicity absorbs all magma

B. Subduction occurs too deep for melting

C. It is a continental-continental convergence without subduction

D. Mantle plumes are absent in this region

5. Which of the following is NOT true about plate tectonics?

A. New crust is formed at divergent boundaries

B. Lithospheric plates move over asthenosphere

C. Convection currents drive plate motion

D. Earthquakes occur only at convergent boundaries

1. C

Explanation: The Benioff Zone is a seismically active inclined plane of earthquake foci along subducting plates (convergent boundaries).

2. C

Explanation: Andesitic volcanoes form where oceanic crust is subducted beneath oceanic crust, producing intermediate magma.

3. C

Explanation: The focus (hypocentre) is the subsurface point where an earthquake originates; the epicentre lies directly above it on the surface.

4. C

Explanation: Isostasy is the state of gravitational balance between the lithosphere and asthenosphere.

5. B

Explanation: Mauna Loa – Shield; Fuji – Stratovolcano; Krakatoa & Taal – Calderas formed due to explosive eruptions.