Gradiometer

A gradiometer measures the gradient (numerical rate of change) of a physical quantity, such as a magnetic field or gravity.

There are at least two types of gradiometer to measure magnetic fields:

Each sensor type responds differently to certain spatial signals.

Axial gradiometers are good for measuring depth and planar ones can measure the signal even from a small exposure, ie they can measure signals even under a lot of noise.

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