Which one of the following geophysical methods can provide information on deep Earth structures (of the order of 1000 km) with highest resolution?
Show Hint
- Seismic methods
- Magnetic methods
- Electrical methods
- Gravity methods
The Correct Option is A
Solution and Explanation
Step 1: Understanding the different geophysical methods.
Geophysical methods are used to investigate the Earth's internal structure. Each method has a different resolution and penetration depth.
Step 2: Seismic methods.
Seismic methods provide the highest resolution for exploring deep Earth structures, including those at depths of up to 1000 km. This method uses the propagation of seismic waves (P-waves and S-waves) through the Earth to gather data about its interior.
Step 3: Comparing with other methods.
Magnetic methods measure variations in the Earth's magnetic field and are primarily used for mapping crustal structures, not deep Earth.
Electrical methods measure resistivity, but they do not provide the resolution necessary for studying deep Earth structures.
Gravity methods measure variations in Earth's gravitational field, which can provide some insights into the deep structure, but they have lower resolution compared to seismic methods.
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