A new data series observed with the remote superconducting gravimeter GWR R038 at the geodetic fundamental station TIGO in Concepción (Chile)

Since November 2002 the Transportable Integrated Geodetic Observatory (TIGO) near Concepción (Chile) is equipped with the superconducting gravimeter GWR R038, installed in a separate gravimeter building at the station. This is the first installation of a superconducting gravimeter in South America and the first prototype of a GWR remote gravimeter in practical operation. Several details of the gravimeter, especially the construction of the Dewar and the cooling system, are optimised to achieve a simplified technical handling. Remote techniques make it possible that the gravimeter can be monitored and controlled from a distant location. The GWR data acquisition system records not only digitally filtered data from the gravity sensor but also several instrumental and environmental data. A first analysis of the observed data over 2.5 years is presented which includes the modelling of the gravitational effect due to precipitation. The initially coarse calibration factor of the sensor can be improved after applying ocean loading corrections to the observed data and comparing the tidal signal with the Wahr–Dehant Earth model.