Question

Match the geophysical methods in Group-I with their associated physical properties in Group-II.

	Group-I		Group-II
P	Magnetic	1	Chargeability
Q	Gravity	2	Electrical conductivity
R	Magnetotelluric	3	Susceptibility
S	Induced Polarization	4	Density

• A. P-3, Q-4, R-2, S-1
• B. P-3, Q-4, R-1, S-2
• C. P-4, Q-3, R-2, S-1
• D. P-2, Q-1, R-4, S-3

Hint:

- Magnetic → Susceptibility.
- Gravity → Density contrasts.
- Magnetotelluric → Electrical conductivity (deep structure).
- Induced Polarization → Chargeability (useful for mineral exploration).

Answer 1

The Correct Option is A

Step 1: Recall the principles of each method.
- Magnetic method: Measures variations in the Earth’s magnetic field due to differences in magnetic susceptibility of rocks. → Property: Susceptibility (3).
- Gravity method: Measures gravitational variations caused by subsurface density contrasts. → Property: Density (4).
- Magnetotelluric method: Uses natural variations in electric and magnetic fields to determine subsurface resistivity/conductivity. → Property: Electrical conductivity (2).
- Induced Polarization (IP): Measures temporary build-up of charge in subsurface materials when subjected to an electric field. → Property: Chargeability (1). Step 2: Matching.
\[ P \rightarrow 3, \quad Q \rightarrow 4, \quad R \rightarrow 2, \quad S \rightarrow 1 \] Final Answer: \[ \boxed{\text{(A) P-3, Q-4, R-2, S-1}} \]