Measured data of the earth's magnetic field should be used as an essential component in exploration (e.g. in deep geothermal energy projects). This is done in SYSEXPL in three steps: collection and measurement of geomagnetic data, separation of the crustal field and subsequent geological decorrelation with spline wavelet methods with regard to geothermally relevant information. In combination with the innovative methods for seismics and gravimetry developed in GEOFÜND and SPE, a systematic analysis of all available data and an integrative synopsis of the results will be provided in close cooperation with the network partner Interstaatliche Hochschule für Technik Buchs NTB, Switzerland, for a systematic and consistent handling of the uncertainties of a geoscientific exploration and thus for risk assessment and evaluation.