Skip to content
Trillium 120 Posthole seismometer half buried in rocky soil connected to a large cable

Trillium 120 Posthole

A very broadband seismometer designed for down-hole deployments.

Get beneath the noise (even urban) and keep your assets secure

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

Stainless Steel Trillium 120 Posthole standing upright

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.


Advanced leveling

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

Flexible deployment Cylindrical down-hole design with 5.6 inch outside diameter facilitates buried deployments.  
Robust design A waterproof, stainless steel
enclosure ensures the sensor is
protected from harsh environments.
Remote corrections Automatic leveling can be remotely initiated to simplify down-hole installation.  
Low Power Low consumption of 230 mW minimizes power source requirements at the site.  
Polar certified This Polar Certified Model is available for operating temperatures down to -50°C.  

Integration Kit

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

Integration kit standing upright with cable connected to another instrument