Gravity Values
In July 2017 an absolute gravity campaign was carried out by IGN. The full report can be downloaded from
here (in Spanish). The absolute gravity meter was the MicrogLacoste FG5 (s/n 211) and the two additional relative gravity meters were both the CG5 model, from SCINTREX (s/n 811 and 1391).
The major goals of the gravity campaigns were:
- Measure an absolute gravity value in the tide gauge benchmark,
- Add an external absolute gravimetric station, as isolated as possible, free from human activity.
Absolute gravity values measured at the AZTI facilities were linked to the reference benchmark with a scintrex gravimetric device. On the other hand, the backbone absolute gravimetric station was located some 50 km away, in the
Sanctuary of Ignacio de Loyola, far from sea tide interaction, quiet environment whitout rail or road vibrations. Moreover, the place has a very symbolic meaning - the development of seismology and seismic prospecting has been called
The Jesuit Science - no better location could be selected to place the main gravimetric station.