Rigorous geoid-from-quasigeoid correction using gravity disturbances

We present rigorous solutions for the geoid-fromquasigeoid correction (GQC) using Taylor expansions of surface gravity disturbances along the vertical from the Earth’s surface to the geoid. One solution takes advantage of the topographic potential bias at the geoid, which can be expressed by a simple formula. This implies that the accurate GQC does not need a terrain correction.