The application of geophysical methods for geological mapping is described for three examples. The first one shows the possibility to device the three-dimensional geological structure by combination of airborne- and borehole-magnetics. The second example presents results of a multi method geophysical mapping survey (magnetics, radiometry, electromagnetics). It demonstrates the importance of multivariate statistical analysis for interpretation of this type of surveying. That it can be applied also to complicate prospecting problems shows the last example, an application of a combined radiometric, magnetic, electromagnetic survey to the prospecting of porphyry mineralization.