Definition - What does Geophysical Exploration mean?
Geophysical Exploration is an applied branch of geophysics that uses physical methods to measure the physical properties of the subsurface, along with the abnormalities in those properties at the surface of the earth. It is commonly used to detect the presence and position of geological deposits that could be economically used. It is also used to get a clear picture of the underlying structures including the spatial allocation of rock units, and to discover structures such as folds, faults and intrusive rocks.
Petropedia explains Geophysical Exploration
Geophysical Exploration methods are used to accumulate the geophysical data that can further be brought into use to prospect economic minerals. This geophysical data is used directly or indirectly to find some geological characteristics in detail such as shear zones, faults, alteration zones folds and other structures. There are various techniques of geophysical Surveys that are used to obtain geophysical data. They are-
- Magnetic Surveys.
- Electromagnetic Surveys.
- Radiometric Surveys.
Magnetic Surveys are mostly used in the exploration of minerals in which a series of magnetometers are connected to an aircraft in a stinger to compute the concentration of the earth's magnetic field; it then permits the revealing of magnetic abnormalities caused by the minerals that are there in the ground. In Radiometric Surveys, digital airborne gamma-ray spectrometers are used to detect and measure low level radiations from natural and man-made sources related to radioactive elements like thorium, potassium, and uranium. On the other hand, electromagnetic Surveys are used to measure the electromagnetic properties of rocks.