中文摘要：

本文利用ASTER GDEM全球数字地形数据和GEBCO的海底地形数据,分别计算了陆地地形和海底地形对我国渤海、黄海、东海、南海区域的海洋重力响应值,也计算了重力响应值的剩余异常与梯度异常.我们将周围地形分为近、中、远三个区域,其中近区和中区采用不同尺度的矩形棱柱,远区采用扇形球壳块模型,同时推导了中区与远区间扇形块重力响应的计算公式.结果表明,在渤海北部、黄海北部、东海南部、北部湾和南海四周距海岸线约100km以内海域,陆地地形的重力响应较大,幅值大于1×10^-5 m/s^2,且陆地地形在海域产生局部重力异常;海底地形对海洋重力异常的影响很大,因此海洋地质调查应使用进行了地形校正的布格重力异常.

英文摘要：

Using the global digital terrain data（ASTER GDEM）and the submarine topography data（GEBCO）,the effects of the land terrain and bathymetry on the marine gravity in the Bohai Sea,the Yellow Sea,the East China Sea,and the South China Sea have been calculated,respectively. The residual gravity anomalies and the gradient anomalies of the effects are then calculated. The terrain surrounding each gravity station is divided into the inner,the middle,and the outer zones.The inner and the middle zones are discretized by rectangular prisms,while the outer zone is divided by fanshaped columns.Meanwhile,the formula for calculating the gravity effect of the terrain between the middle and outer zone was derived. The computation results show that in the northern Bohai Sea,the northern Yellow Sea,the southern East China Sea,the North Bay,and the South China Sea,within the area of 100 kilometers offshore,the amplitude of gravity effect of land terrain is larger than 1×10^-5 m/s^2,and the residual gravity anomalies are yielded by the land terrain in these seas.The sea floor topography effects greatly on the marine gravity anomaly.Thus,terrain correction must be applied to the Bouguer gravity anomaly in marine geological surveys.