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We present results from interpretation of a 3D seismic data set, located within the NW German sedimentary basin, as part of the Southern Permian Basin. We focused on the development of faults, the timing of deformation, the amount of displacement during multiphase deformation, strain partitioning, and the interaction between salt movements and faulting. We recognised the central fault zone of the study area to be the Aller-lineament, an important NW-trending fault zone within the superimposed Central European Basin System. From structural and sedimentological interpretations we derived the following evolution: (1) E–W extension during Permian rifting, (2) N–S extension within cover sediments, and E–W transtension affecting both basement and cover, contemporaneously during Late Triassic and Jurassic, (3) regional subsidence of the Lower Saxony Basin during Late Jurassic/Early Cretaceous, (4) N–S compression within cover sediments, and E–W transpression affecting both basement and cover, contemporaneously during Late Cretaceous/Early Tertiary inversion and (5) major subsidence and salt diapir rise during the Cenozoic. We suggest that the heterogeneity in distribution and timing of deformation in the working area was controlled by pre-existing faults and variations in salt thickness, which led to stress perturbations and therefore local strain partitioning. We observed coupling and decoupling between pre- and post-Zechstein salt units: in decoupled areas deformation occurred only within post-salt units, whereas in coupled areas deformation occurred in both post- and pre-salt units, and is characterised by strike-slip faulting.

This article describes the use of an artificial neural network to predict area-wide reservoir parameters by classifying multi-attributes derived from 3D seismic data. Special emphasis is placed on the comparison between the artificial neural network and geostatistical appoaches.

The attenuation in the vicinity of the geothermal anomaly at Urach was determined by means of two near‐vertical reflection profiles. The attenuation in the sediments and in the upper crust (3‐4 km depth) was estimated by interpretation of the first (refracted) arrivals. For calculating the attenuation, the amplitude decay with respect to distance was used. Corrections for the spread factor, i.e. the geometric amplitude divergence was deduced from the traveltime curves. Below the anomaly, higher attenuation values (Q−1∼ 0.008) were observed compared with those in the undisturbed crust (Q−1∼ 0.002). This effect is probably due to the cracks and fissures in the upper part of the crystalline basement. The attenuation in the middle and lower crust was determined using near‐vertical reflections from this depth interval. The use of the spectral ratio method leads to higher values of the effective attenuation Q−1eff below the heat flow anomaly compared to those of the‘ normal’crust. This zone of high Q−1eff coincides with the low velocity body below the heat flow anomaly. Both effects, the higher attenuation and the lower velocities, could be caused by high temperatures, cracks and fissures in the crust.

The statistical treatment of deep seismic reflections from several different geological units has resulted in different reflectivity histograms. Reflectivity in old and cold shields differs significantly from that in younger, warmer areas. In the shields reflectivity is generally poor and concentrated in the upper crust whilst Caledonian and Variscan areas show strong reflecting lamellae in their lower crust. Also the length of the reflecting elements varies with age and heat flow. The lower crust in young areas is a zone of a strong viscosity minimum as derived from model studies with a temperature dependent rheology. The subhorizontal reflecting lamellae in the lower crust are considered to have been created in a large-scale high-temperature, low-viscosity ordering process whose remnants are still preserved today. Local-scale differences of reflectivity histograms define certain subprovinces which can be distinguished by their specific patterns.