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The super-spring uses a spring system with a natural period of 60s
and is provided with oscillation dampening. This assembly removes
the micro-seismic noise (around 6s-16s in period) from the
measurements but is unable to compensate for larger seismic activity

such as those generated from; earthquake events, extreme weather
over oceans and a variety of other sources, mainly man made. The
SGF operates the FG5 at high frequency, aiming to take

measurements each week.
Very accurate and precise timing of the occurrence of these
optical fringes is done using an atomic rubidium clock that is also
referenced to absolute standards.

The measurement is directly tied to international standards, and
this is what makes the FG5 an absolute gravimeter. By basing the
measurement on these standards, the system is inherently calibrated

and will neither drift nor tare over time.
FG5 Applications:
- Geophysical Research:

• Vertical crustal motion detection;
• Complementary verification of displacements measured with
GPS and VLBI;

• Volcanic magma flow monitoring;
• Earthquake research;
• Long period tidal monitoring and earth inelasticity modeling.
- Environmental Monitoring:

• Water table monitoring in deep and/or multiple aquifers;
• Nuclear waste management and cleanup;
• Global sea level studies for global warming.

- Exploration and Resource Management:
• Oil exploration;
• Mineral exploration.
- Precision Measurements and Calibrations:

• Pressure transducer and load cell calibration;
• Calibration of superconducting of other high precision relative
gravity meters.

- Inertial Navigation:
• Gravity reference station determinations;
• Relative gravity network control points;

• Establishing geodetic tie points for gravity networks;
• Defining the geoid.

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