Nanometrics’ industry-leading portfolio of Trillium seismometers includes a posthole variant that is revolutionizing the way seismologists deploy instruments and collect seismic data.

Trillium Posthole Seismometer device

Reliability, repeatability, outstanding performance

The Trillium Posthole Seismometer is a very broadband seismometer designed for down-hole deployments. The instrument is housed in a stainless steel enclosure incorporating a high-pressure, marine-grade connector making it suitable for uncased buried/posthole installations. An advanced levelling system reorients the internal seismometer mechanism to true vertical, correcting for installations tilted up to ±9 degrees.

Local, regional & teleseismic studies

The Trillium PH is ideal for local, regional and teleseismic studies having a response flat to velocity from 120 seconds to 150 Hz and exceptionally low self-noise. Operators will appreciate the low power consumption, automatic mass centering and robust no-mass lock design inherent in all Trillium seismometers.

A highly integrated station solution

When using the Trillium 120 PH with our popular Centaur digitizer, you’ll have access to a digital leveling bubble through the Centaur GUI. The virtual leveling bubble makes for easy leveling down a dark hole, or once buried, gives you the ability to check levelness at any time.


  • The ability to get beneath the noise, even in urban environments, and keep your assets secure.

  • Automatic leveling can be remotely initiated for corrections of up to ±9 degrees, simplifying down-hole installation.

  • The axis stack is mechanically leveled to ensure that the vertical axis does
    not couple horizontal noise.

  • A robust, waterproof, stainless steel enclosure ensures the sensor is
    protected from hostile environments.

  • Cylindrical down-hole design facilitates buried deployments.

  • Low power consumption minimizes power source requirements at the site.

Also available:

  • Trillium 120 Posthole ±5 degree tilt models, Trillium 120 Borehole and Trillium Horizon for vault or shallow direct bury with 1200 V-s/m or 2000 V-s/m sensitivity


Polar certified logo


Polar Certified Model available for
operating temperatures down to -50°C




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