Refinement Of Provincial And Municipal Geoid

The article describes basic theory and principles of precise determination of local geoid. Methods for the precise determination of local geoid have been studied and put forward in this research, which include the geometric (GPS/level ing) method, the gravimetric method and the combined method.The disquisition emphases of the article is gravitation method with Remove-Restore Technique account geoid and quasi-geoid . There are methods that gravity data of observation and gravity anomalies which should be ranged in forms of matrix (Gridding methods). Technique way and Model forms would be explained for the target. Data of the digital terrain model (DTM) would be computed . The result would be topography correction and indirect infection to the geoid . How to select the Whole World Gravity Field Model is the question that we must pay attention to in the real application to determination of local geoid .We applied all available data which come from the region in east china area: north-south 52 kilometers, western-east 100 kilometers based on the above theory. We have discussed questions we should pay attention to in the determination of local geoid and calculated the local geoid with gravity observation data 4870 and GPS/leveling point data 65 which are DTM that distinguish rate is 100 metre .and WDM94 and EGM96 Whole World gravity Field Model.We have tested the geoid of the area with Remove-Restore Technique and Fast Fourier Transform(FFT)...