Mean gravity anomaly values which represent 1 degree x 1 degree surface areas can be predicted on the continents by geophysical gravity correlation methods whether or nor measured gravity data exists within those 1 degree x 1 degree areas. These methods take into consideration the earth's structure, composition, and response to changes in surficial mass distribution by means of observed or computed correlations between gravity and other geophysical parameters within geologic/tectonic provinces. Linear basic prediction functions, used to describe and predict the relationships between gravity and elevation, are shown to be a natural consequence of the properties of gravity reduction procedures and the observed behavior of gravity anomalies within structurally homogeneous regions. (Modified author abstract).