Abstract
Physical meaning of the Bouguer reduction is reconsidered with respect to the vertical gradient of gravity anomaly. An iterative method is proposed for deriving the sealevel Bouguer anomaly and its vertical gradient from the conventional Bouguer anomaly at ground level. Actual computation results from gravity and topographic data of mountainous areas remind us of the significance of vertical gravity gradient for reducing the Bouguer anomaly to sealevel.
