Sub-seismic deformation on different scales in the North German Basin

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The evolution of a sedimentary basin is most particularly affected by deformation. Largescale, subsurface deformation is typically identified by the interpretation of seismic data and evaluated by palinspastic reconstruction. These studies also show, however, that sub-seismic small-scale fractures play a significant role: they may accomodate a significant proportion of the total strain (up to 50%) during basin evolution, laterial variation may cause compartmentalised deposits and reservoirs, and fracture networks may act as conduits for diagenetic fluids. In the Northgerman Basin these virtually unknown aspects require an analysis of location, orientation and length distribution of the fracture systems with different methods for determining a) the magnitude of deformation, b) the strain accumulation in space and time, and c) the processes that control a) and b) during basin evolution under varying kinematic constraints. To address these topics, our study aims to 1) quantify and predict areas of high- or low-strain accumulation in the NGB with seismic interpretation and 3D retro-deformation, 2) validate these predictions with fractal analysis of fracture systems and calibration with drill hole and sample data, and 3) compare observed and predicted strain patterns with those from scaled analogue experiments to unravel the relationship at different scale lengths within structures representative of units in the NGB. For this purpose we have chosen the Völkersen area where both appropriate well and 3D seismic data from oil industry are available.