| In order to fully tap the application potential by using marine gravity data to inverse seafloor topography, the inversion approach with geoid height is explored in this paper. Numerical analysis was carried out in the sea area where the inflection point of Hawaii-Emperor seamount chain is located. Firstly, associated Legendre functions (ALFs) was calculated by Belikov method, and geoid height model with 1-angular resolution was obtained by EIGEN-6C4 gravity field model. Then, the frequency range of seafloor topography inversion using geoid height was obtained by analyzing the characteristics of scale function and transform function, while studying the coherence between geoid height and seafloor topography and characteristics of geoid height itself. Finally, seafloor topography model (BNT model) was derived by geoid height in the test area. Compared with ETOPO1 model and some other models, the results show that the number of checking points accounts for 70.60% considering BNT model when checking difference is less than RMS, which is more centralized than normal distribution. The accuracy of BNT model is lower than that of ETOPO1 model and increases with the increase of sea depth. Relative error diverges greatly when sea depth is less than 1 000 m.Moreover, the accuracy of ETOPO1 model is the highest, and there is little difference between GEBCO model and DTU10 model. |
