Electrodynamic geophones (hereinafter referred to as geophones) are designed to register fluctuations in the external environment and convert them into electrical signals.
Since two main types of waves are most often recorded in seismic exploration — longitudinal and transverse, there are two main types of geophones — horizontal and vertical.
The device consists of a magnetic core surrounded by an electric coil. The core and the housing are bonded to each other. The coil is also attached to the body with thin springs. At the moment of the passage of the wave, vibration occurs, which is transmitted to the housing, and the coil inside it tends to remain stationary. The movement of the magnet inside the coil induces an electric current, which depends on the frequency and intensity of vibrations.
Modern geophones, also called exploratory seismographs, use electromechanical converters in their mechanism, with the help of which wave vibrations are converted into current fluctuations by an amplifier and a recording loop oscilloscope.
Depending on the application conditions, geophones are installed in the necessary enclosures or receiving seismic equipment.