Instruments that are deployed on the ONC observatories that are of concern to the Royal Canadian Navy (RCN) and US Navy (USN) are called Tier 1 instruments. Currently, three types of instruments fall into this category:

Seismic instruments

Passive acoustic instruments

Magnetometers

The RCN and USN have the ability to control (divert) the realtime data flow from the Tier 1 instruments to the ONC data archive.

Seismic Instruments

At present, three manufacturers of seismic instruments are deployed (Güralp, Nanometrics, RBR)

The high rate raw data stream is subject to diverts, while the low rate raw data stream is not. Diverted high rate raw data may be returned to ONC if the navies determine there is nothing of concern in the data.

For seismic instruments (Güralp) that were deployed during the years 2009 to 2013,

Hydrophones

Hydrophone WAV audio file data product documentation, sub-page: Hydrophone acquisition and diversion options documentation

At present, two manufacturers of hydrophones are deployed (Ocean Sonics, Jasco Applied Sciences). A mix of single element and four element hydrophone arrays are deployed. Two models of Ocean Sonics hydrophones

icHFs deployed with:

icAFs deployed with:

On the offshore observatory (formerly NEPTUNE) and inshore observatories (formerly VENUS), the raw acoustic data stream is subject to diverts, while the low resolution FFT data stream is not. Near-shore observatories are in general not subject to diverts. Diverted raw acoustic data may be returned to ONC if the navies determine there is nothing of concern in the data.

Magnetometers

The first magnetometer will be installed in 2025. While this magnetometer (LEMI-089) will be subject diverts, the details of this are still to be worked out.

Historical Hydrophones

Naxys

Ocean Sonics icListen HF Hydrophone

Ocean Sonics icListen LF Hydrophone

VENUS

IOS

Ocean Sonics icListen LF Hydrophone