Ground motion measurement is a vital source of data, providing valuable information on subsurface lithology and structure both on land and at sea.

While onshore investigations are straightforward, offshore they can often pose a range of difficulties such as time limitations due to high power consumption, noise interference from currents, and poor seabed coupling. And while broadband seismometers in OBSs are now relatively common, they can be too large and expensive for use on many operations (e.g. active seismic projects where higher frequency signals are recorded).

To address this, K.U.M. has developed a standalone subsea Geophone to optimise the accuracy of data collection. It delivers outstanding signal-to-noise ratio with a special pressure housing for 3C-Geophones that resides externally from the main instrument and is connected by just a flexible cable. This way, the Geophone is decoupled from any possible unwanted noise produced by the main instrument itself (e.g. the OBS) that may lead to inaccuracies within the data.

Our three-part Geophone features a compact, grooved titanium design tailored to ensure best seafloor coupling while simultaneously providing excellent protection from corrosion. The Geophone is best used with a range of K.U.M.’s OBS instruments, all of which have been designed and tested together. However, the device is equally compatible with a wide range of third-party instruments.


Features & Benefits


  • Subsea seismic data acquisition as part of the K.U.M. OBS or any other marine instrument


  • Compact design
  • Optimised grooved shape for best seabed coupling
  • Implemented gravity for free fall
  • High signal-to-noise ratio
  • Light and corrosion-resistant titanium
  • Low noise irrespective of current


Technical Data

Frequency range4.5Hz – operates at +/-30°, 10Hz – Omnidirectional, 14Hz – Omnidirectional, 30Hz – Omnidirectional
Damping (open circuit)0.56% (±5%)
Moving mass11.1g
Sensitivity (open circuit)28.8V/m/s (±5%)
Sensors3 orthogonal geophones
Operational depth6000m
DimensionsDiameter – 160mm, Height – 57mm
Weight2.6kg (air), 1.6kg (water)