Diurnal correction in magnetic survey data accounts for:
Show Hint
- geomagnetic polarity reversals
- charged particles in ionosphere
- the westward drift of the Earth’s magnetic field
- the lunar magnetic field
The Correct Option is B
Solution and Explanation
Step 1: Understanding diurnal variations. The Earth’s magnetic field undergoes short-term fluctuations throughout the day due to changes in the ionosphere caused by solar radiation.
Step 2: Purpose of diurnal correction. Magnetometers record total magnetic field, which can be influenced by these ionospheric variations. Diurnal correction removes these temporal effects to reveal local geological anomalies.
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