Solution and Comparison of High Order Term of Analytical Continuation

In order to improve the accuracy of earth gravity field measurements，a high order term for analytical continuation must be considered in practical applications. The high order term for analytical continuation solution was derived using the direct derivative method and iterative derivative method，which were compared with the traditional recursion method. The general recursion formula is obtained using the iterative derivative method. The formula shows that the classical recursion method has the same form as iterative derivative method after ignoring the little quantity term. An analysis also showsthat ananalytical continuation solution can be induced into the solution of different order derivatives for gravity anomalies along the plumb direction. This analytical continuation experiment was applied to the 50×50 area. and a n，term，and n2 term were calculated in this experiment. The reason for this difference may stem from computation error in the integral operation.