The correct answer is A) Geophysical surveys.
Geophysical surveys are a type of non-invasive exploration technique that uses physical properties of the Earth to detect and map subsurface structures. They are used in a variety of applications, including mineral exploration, groundwater exploration, and environmental monitoring.
There are many different types of geophysical surveys, each with its own advantages and disadvantages. Some common types of geophysical surveys used in mineral exploration include:
- Gravity surveys: These surveys measure the Earth’s gravitational field, which can be affected by the presence of dense materials such as ore bodies.
- Magnetic surveys: These surveys measure the Earth’s magnetic field, which can be affected by the presence of magnetic materials such as ore bodies.
- Seismic surveys: These surveys use sound waves to create a map of the subsurface. Seismic surveys can be very effective in detecting deep-seated mineral deposits.
- Electrical resistivity surveys: These surveys measure the electrical resistivity of the Earth, which can be affected by the presence of water and minerals.
Geophysical surveys are a valuable tool for mineral exploration. They can be used to identify potential mineral deposits, to map the extent of known deposits, and to monitor the progress of mining operations.
Aerial photography is a technique that uses photographs taken from an airplane or satellite to map the Earth’s surface. Aerial photographs can be used to identify potential mineral deposits, to map the extent of known deposits, and to monitor the progress of mining operations. However, aerial photography is not as effective as geophysical surveys for detecting deep-seated mineral deposits.
Satellite imagery is a technique that uses images taken from a satellite to map the Earth’s surface. Satellite imagery can be used to identify potential mineral deposits, to map the extent of known deposits, and to monitor the progress of mining operations. However, satellite imagery is not as effective as geophysical surveys for detecting deep-seated mineral deposits.
Ground-penetrating radar (GPR) is a geophysical technique that uses radar waves to create a map of the subsurface. GPR can be used to detect buried objects, such as pipes, cables, and foundations. It can also be used to detect subsurface structures, such as voids, buried streams, and buried archaeological features. However, GPR is not as effective as geophysical surveys for detecting deep-seated mineral deposits.