Application of remove-restore method in iterative algorithm for subma-rine terrain analysis based on gravity anomaly data
High-precision seafloor topography maps are of great significance in earth science research.Due to the difficulties of measuring high-resolution global coverage of bathymetry directly,a large-scale prediction of seafloor topography relies on grav-ity data mostly.So,various methods are employed for predicting seafloor topography from gravity data,such as the frequency-domain polarization method,geological-gravity method and iterative analytical method.However,there are some drawbacks in these methods.In this paper,remove-restore method is applied to deal with the issues related to the far-field influences in the iterative analytical method.By combining existing bathymetric models,the simulated experiments are designed to discuss sepa-ration methods for the far-field influences and their accuracies are also assessed in inverting seafloor topography.Ultimately,the effectiveness of the remove-restore method is validated in improving seafloor topography by applying to the region of 13.85°N—14.85°N latitude and 117.25°E—118.25°E longitude in the South China Sea.Compared with actual bathymetric data from NGDC,it is concluded that the root mean square error is 90.3 meters and relative error is up to 2.11%.This provides a potential means for improving sparse bathymetric data in ship-measuring areas with high-precision gravity data and the analyti-cal iterative algorithm.