The gravity observation adjustment is studied having in view to take full advantage of the modern technology of gravity measurement. We present here results of a test performed with the mathematical model proposed by Dias and Escobar (2001), here named D&E model, on the adjustment of gravity observations carried out on network design. The data set of the Brazilian Fundamental Gravity Network (BGFN) was used as case study. With about 1900 mGal gravity range and 11 control station (Torge et al, 1994) the BGFN was stablished with the use of LaCoste&Romberg (LCR), model G, gravimeters. The observables involved in the model are instrumental reading, calibration functions of the gravimeters used and the absolute gravity values at the control stations. Gravity<br>values at the gravity stations and datum scale factors for each gravimeter were determined by least square method. The results indicate good adaptation of D&E model to network adjustments. The gravity value in the IFE-172 station control, located in Santa Maria, had the largest estimated correction of –12.6 mGal (1 mGal=10 nm/s2), and the standard deviation for an observed reading was estimated in 25 mGal, with the largest residual estimated in 43 mGal. The largest correction to the calibration functions was 4,3.10-6 mGal/instrumental unit. Considering the recent improvement on instrumental technology in gravimetry, the D&E model was modified to take into account a possible non linear datum function, in a 1900 mGal range network, and to check its significance<br>for a mGal precision.


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