Question

The point where an earthquake originates is known as

• A. Epicentre
• B. Iso-seismal
• C. Co-seismal
• D. Focus

Hint:

Remember the difference:
- Focus is the underground origin.
- Epicenter is the surface point directly above the focus.
Think of "Epi-" as a prefix meaning "upon" or "over," so the epicenter is upon the center.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
The question asks for the specific term for the point of origin of an earthquake.

Step 2: Detailed Explanation:
Let's define the given terms related to earthquakes:
-

Focus (or Hypocenter): This is the point

within the Earth along a fault where the initial rupture and release of energy occurs.
It is the true origin point of the earthquake.
-

Epicenter: This is the point on the

Earth's surface directly above the focus.
It is the location where the earthquake's effects are often the most intense.
-

Iso-seismal line: A line on a map connecting points of equal earthquake intensity.
-

Co-seismal line: A line on a map connecting points where the seismic waves arrive at the same time.
The question asks for the point where the earthquake originates, which is the focus.

Step 3: Final Answer:
The point where an earthquake originates is known as the focus.
This corresponds to option (D).