We propose a modified centroid method to compute the depth to the bottom of magnetic sources (DBMS) based on a fractal source distribution. This approach provides better estimates than the assumption of an uncorrelated source distribution. We apply our approach to a recently compiled homogeneous set of aeromagnetic data from Germany. The deepest DBMS values are found for some large basin areas, i.e., the Molasse basin and parts of the North German basin. Smaller DBMS were estimated for the Moldanubian region in southern Germany and the northern part of the North German basin. A comparison of DBMS with heat-flow data, crustal temperatures at 3-km depths, and Moho depth indicates that DBMS is controlled by the geothermal condition of the earth’s crust in Germany and lithologic changes. Although the Upper Rhine graben and the Moldanubian region are characterized by small DBMS, a change in DBMS values in northern Germany seems to be related to the Elbe lineament.

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The detection of completely preserved maar structures is important not only for underground mapping but also for paleoclimate research because laminated maar lake sediments may contain a very detailed archive of climate history. Objective evidence for the existence of such structures can only be provided by geophysics and boreholes. The combination of gravity and magnetic ground surveys appears to be an excellent tool to detect and identify buried maar structures. Their prominent properties are an almost circular gravity minimum corresponding to a crater filled with limnic sediments of low density, and a magnetic anomaly caused by a pyroclastic or basaltic body in the diatreme which indicates the volcanic character. Seismic measurements provide the most detailed information about the internal structure of the maar sediments. Zones of low seismic reflectivity and very low density represent sediments of the late maar-lake period. The early lake period is indicated by debris flow deposits and turbidites represented by seismic reflectors. The seismic sections clearly reveal the bowl-like structure of the maar. Outside this bowl-like structure, there are only a few reflections, which represent the basement. Taking into account the shape of the gravity anomaly, seismic information allows geometrical modelling of the maar structure. Optimal drilling sites can be selected based on the results of geophysical surveying. Comparing the results of combined geophysical surveys above two maar structures of different ages yields a marked similarity in their geophysical pattern.

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SUMMARY Anomalies of the Earth's total magnetic field reveal important information about crustal structures. For the first time, a homogenous map of anomalies of the Earth's total magnetic field for the whole of Germany is available. The map is based on 50 shipborne, airborne and ground surveys, which were conducted between 1960 and 1990 and complemented by 17 new surveys after German reunification. The map, with a grid spacing of 100 m, consistently images the entire anomaly pattern in Germany at an altitude of 1000 m a.s.l. related to the DGRF 1980, epoch 1980.0. Because of these reference parameters and consideration of new data, the resolution of this map is higher than any previously published map. The homogenized and complete data set enables the distinction of different magnetic anomalies and – by observing their vector character – the identification of magnetic sources from different stages of the geological history. Since the map images the superposition of magnetic source anomalies from different depths and therefore combines long‐ and short‐wavelength spectrums within one data set, it offers new insights into crustal structures. Not only regional tectonic units, such as the Variscan terranes in south and central Germany, or the extent of old Scandinavian crust under North Germany, as a relict of the collision between Baltica and Avalonia are imaged, but also details of local structures such as the volcanic areas of the Vogelsberg and the Eifel region. Therefore, the new data set can be used for work on modern topics in geosciences that cover both fundamental and applied research – for example, the structural and petrophysical characterization of the crust, its rheology and geodynamic evolution, or even hydrocarbon exploration. The gridded data is available as an electronic supplement to this paper.

The Heidelberg Basin (HDB) hosts one of the thickest Quaternary sediment successions in central Europe. To establish a reliable Middle and Upper Pleistocene chronology for a recently drilled core from the depocentre of the Heidelberg Basin, we applied multiple luminescence dating approaches, including quartz optically stimulated luminescence (OSL), two feldspar post-IR IRSL protocols using second IR stimulation temperatures of 225°C (pIRIR 225 ) and 290°C (pIRIR 290 ), and two fading correction models. Relatively high anomalous fading was observed for both the pIRIR 225 and pIRIR 290 signals, with mean fading rates of 2.13AE0.27 and 2.08AE0.49%/decade, respectively. Poor dose recovery behaviour of the pIRIR 290 signal suggests that the pIRIR 290 ages are not reliable. The comparison of two fading correction methods for the K-feldspar ages indicates that the correction method proposed by Kars et al.