Hunt, T.M. 1975 Repeat gravity measurements at Wairakei 1961-1974. [s.l.]: [s.n.]. Report / Geophysics Division 111 23 p.
Abstract: Repeat gravity measurements made to examine the effects of mass changes associated with exploitation of the Wairakei Geothermal Field are described. The standard errors of the gravity values are generally about 0.1 micro N/kg, but observations over several days suggest the accuracy is about 0.3 micro N/kg. The effect of ground noise in the geothermal area is negligible. Differences between surveys caused by topographic and groundwater level changes are less than 0.2 micro N/kg, and less than 0.3 micro N/kg for uncertainties in instrument calibration. Differences due to regional gravity variations are thought to be negligible (auth.)