High sensitivity geophone

摘要

A geophone including a plurality of ferromagnetic masses (e.g., magnets) disposed to oscillate on one or more compliant elements (e.g., springs) in a manner that produces a steep flux gradient at one or more conductive coils is disclosed. The magnetic masses are positioned with like poles facing each other so as to compress the magnetic field gradient. The coils may be positioned in the flux gap either between the magnets, in close proximity to the magnets, or surrounding the magnets. Vibration measurements may then be detected from the movement of at least one of the magnetic masses.