A magnetometer is a scientific instrument used to measure the strength and/or direction of the magnetic field. The Earth’s magnetic field (the so magnetosphere) varies from place to place, for various reasons such as inhomogeneity of rocks and the interaction between charged particles from the Sun and the magnetosphere. A mass of ferromagnetic material creates though a detectable disturbance in this magnetic field. This magnetic anomaly produces a weak alternating magnetic field that is picked up by the magnetometer, amplified electronically, and fed to the CPT-Logger and subsequently recorded on a computer.
Magnetometers are typically used in ground-based electromagnetic geophysical surveys (such as magnetotellurics and magnetic surveys) to assist with detecting mineralization and corresponding geological structures and the detection of buried or submerged objects.