Study on establishing local marine geomagnetic field model

Establishment local marine geomagnetic field model with marine geomagnetic observation is very important for marine research and exploration. Four methods, which are Taylor polynomial, Legendre polynomial, spline surface function and multi-surface function, are introduced into the work. Some key problems in the establishment of the model by the four methods are studied and discussed in the paper. In order to further improve the modeling accuracies of the four methods, zoning modeling is also studied and given out. Integrated the above researches, an optimum method, multi-surface function with zoning modeling, is presented by comparing and analyzing the four methods in actual applications, which achieves the model accuracy better than 5 nT in establishing local marine geomagnetic field finally.