The main purpose of this paper is to evaluate the first-order term of the Molodenskii series by using different approaches, which approaches are: the solution given by Molodenskii; the solution using the vertical gradient in accordance with Moritz as an approximation of <img border=0 width=32 height=32 src="../../../../img/revistas/bcg/v16n4/a05simb03.jpg"> term; and by using the terrain correction which is an approximation for <img border=0 width=32 height=32 src="../../../../img/revistas/bcg/v16n4/a05simb03.jpg">. The two first solutions are coherent with each other under the conditions here analyzed. The comparison was made in terms of the first order height anomaly. Considering the final quasi-geoid, the use of terrain correction instead of the <img border=0 width=32 height=32 src="../../../../img/revistas/bcg/v16n4/a05simb03.jpg">term was efficient in terms of the evaluation by using independent data; in this case, 42 GPS points on benchmarks. The methodology, results and discussions, conclusions and practical recommendations are presented in the paper.
Quasi-Geoid; Free-air Gravity Anomaly; Geodetic Boundary Value Problem
