# GEM9 위성자료와 지상자료의 조합에 의한 남한지역의 GRS80 중력지오이드

• 조규전 (경기대학교 공과대학 토목공학과) ;
• 이영진 (서울시립대, 한양대 공과대학 토목공학과) ;
• 조봉환 (국방과학연구소)
The gravimetric geoid of the South Korea Region was computed on Geodetic Reference System 1980(GRS80) using a combination of satellite-derived potential coefficients and terrestrial gravaty data. $10^{\prime}{\times}10^{\prime}$ mean gravity anomalies were obtained from surface gravity data for the outer zones, $1^{\circ}{\times}1^{\circ}$ equal area mean anomalies were used for the inner zones, and point gravity anomalies were used for the innermost zones in the Stokes integration. The GRS80 potential coefficients were obtained from modification of GEM9 data and Integration was extended over a spherical cap of $30^{\circ}$ from the integration area. The results of a free-air geoid show that the systematic mean difference of approximately 2~3m in comparison of OSU89B model.