This research aims to analyze the airborne gravity data accuracy using cross-over adjustment for geoid determination in Chao Phraya basin. The data sets were categorized into the cases of with and without cross-over adjustment. Both types of the data sets were then reduced to mean sea level by means of downward continuation to be compared with terrestrial gravity data sets. The adjusted data yielded the more accurate result. The root mean square (rms) value of it was 3.991 mGal while the rms value was 4.485 mGal for the case of no data adjustment. The computed geoid heights using both types of the data were compared with the geoid computed using GNSS/Leveling co-points. The geoid using the adjusted data yielded the more accurate result. The rms value of it was 0.096 m. while the rms value was 0.1 m. for the case of no data adjustment.
Keywords
Cross-over Adjustment, Geoid Model, Downward Continuation, Least Squares Collocation,GNSS/Leveling co-points