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

The Trillium Posthole Seismometer is a very broadband seismometer designed for down-hole deployments.

Reliability, repeatability, outstanding performance

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 leveling system allows the instrument to self-correct over a tilt range of ±5 degrees (±10 degrees optional).

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 self-noise below the NLNM at 100 seconds. 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 ±5 degrees (±10 degrees optional), 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 with 5.6 inch outside diameter facilitates buried deployments
    • Low power consumption of 490 mW minimizes power source requirements at the site

    Integration Kit

    We now offer an integration kit that allows you to combine the Titan Posthole with a Trillium 120 Posthole or Trillium 120 Borehole seismometer for a Cascadia that has an even lower noise floor and greater dynamic range. 

    Also available:


    Polar certified logo


    Ultra-low temperature options available



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