The Trillium Borehole Seismometer is a very broadband seismometer designed for cased borehole deployments. The instrument is housed in a stainless steel enclosure incorporating a hole-lock mechanism to allow the instrument to be coupled to a deep borehole casing. Instrument recovery is aided by a fail-safe holelock release mechanism that prevents jamming to the casement during removal.
An advanced levelling system allows the unit to operate over a tilt range of +/-5 degrees. The axis stack is mechanically levelled to ensure that the vertical axis does not couple horizontal noise.