The theoretical model study of the Tiltdepth method shows that this method is effective in judging the buried depth of

the geological body, and also has superiority in determining the buried depth of the deepseated field source. The determination of

the buried depth of the deepseated field source is hence extended to the determination of the buried depth of the basement with

the purpose of providing theoretical guarantee for practical data processing. The application of the Tiltdepth method to practice

revealed that the existence of the highfrequency component had some influence on the judgment of the basement depth. The upward

continuation with the iterative method was therefore used to eliminate the highfrequency component, with ideal result attained.

The achievements obtained in this study have brought easiness and rapidness to aeromagnetic data processing.