Downward Continuation of Airborne Gravimetry on Land Using Geopotential Model and Terrain Information

In order to evade the ill-posedness of downward continuation for airborne gravity data using traditional inverse Poisson integral,in a recent published article,apractical downward continuation method of airborne gravity data was used for the sea surveying areas using the differential conception in navigation and location for reference,in which the continuation corrections are calculated using ultra-high-degree geopotential model.In this paper,we continue using the same idea and develop the method to the application for land surveying areas.It suggests that terrain Information can be used to improve the calculated accuracy of continuation correction from geopotential model.The differential of local topographic corrections on flying height and corresponding ground point is added to the continuation correction from geopotential model,and it makes up the total continuation correction.It is ultimately realized to continue airborne gravity measurements to the ground in full frequency extension.EGM2008 geopotential model,ground gravity data and digital elevation model in high resolution are used as a case study to prove the efficiency of the new method.