Abstract

This scientific article proved a base of using RTM anomalies for construction of nation-al gravity anomaly database in country like Vietnam where the mountainous regions occu-py 3/4 area. Article shows that then height differences between real topographical surface and average topographical surface vary more than 23,244 m, Faye anomalies have been affected by systematic errors appeared from residual topographical masses between real topographical surface and average topographical surface, additionally residual topograph-ical masses characterize influence of geoid waves with average frequaences. When DTM 3” x 3” is accepted for real topographical surface of the Earth, DTM 5’ x 5’ – for average topographical surface of the Earth, research result shows that in mountainous regions from northwestern regions along ranges Truong Son to north of Tay Nguyen plateau on territo-ry of Vietnam with heights more than 2 km, height differences between real topographical surface and average topographical surface always are more than 23,244 m, even reach some hundred meteres. That shows that in Vietnam national gravity anomaly database can be constructed based on the RTM anomalies.