The correct Answer is A-3, B-2, C-4, D-1
Explanation
This question pertains to fundamental terminology associated with earthquakes and Earth's internal structure. Understanding these terms is crucial for comprehending seismic activity and geological processes.
Statement-wise Analysis
- A. Focus (3. Point where energy is released during an earthquake)
Correct. The focus, also known as the hypocentre, is the point within the Earth where the rupture of rock occurs, and seismic energy is first released during an earthquake. - B. Epicentre (2. Point on the surface nearest to the energy release)
Correct. The epicentre is the point on the Earth's surface directly above the focus (hypocentre) of an earthquake. It is typically where the greatest damage occurs. - C. Fault (4. Sharp break in the crustal rocks)
Correct. A fault is a fracture or zone of fractures between two blocks of rock. Faults allow the blocks to move relative to each other, and earthquakes are caused by sudden movement along these faults. - D. Magma (1. Molten material in the upper mantle)
Correct. Magma is molten rock material found beneath the Earth's surface, primarily originating in the upper mantle and lower crust. When it erupts onto the surface, it is called lava.
Key Takeaway
The focus is the origin of an earthquake within the Earth, the epicentre is the point on the surface directly above it, a fault is a break in the crust where movement occurs, and magma is molten rock beneath the surface.