Trillium 120 Posthole

Trillium 120 Posthole Broadband Seismometer

The Trillium 120PH Posthole Seismometer is a very broadband seismometer designed for down-hole deployments at depths to 30 meters. The instrument is housed in a stainless steel enclosure incorporating a high-pressure marine grade connector making it ideally suited to uncased posthole installations. An advanced leveling system allows the unit to operate over a tilt range of +/-10 degrees. The Trillium 120PH is ideal for local, regional and tele-seismic studies having a response flat to velocity from 120 seconds to 145 Hz and a self noise below the NLNM from 35 seconds to 10 Hz. Operators will appreciate the low power consumption, remote mass centering and robust no-mass lock design inherent in all Trillium seismometers.


  • Automatic motorized mass centering can be remotely initiated to correct leveling of up to +/- 10 degrees, simplifying down-hole installatio
  • A robust, waterproof, stainless steel enclosure ensures the sensor is protected from hostile environments
  • The down-hole design includes a 6 inch diameter casing, single marine grade connector and a centered attachment eye bolt on the top surface
  • Low power consumption of 650mw minimizes power source requirements at the site
  • Exceptional self noise below NLNM 35s to 10 Hz is well suited for quiet down-hole installations