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Along-fault lithological heterogeneity is observed in all fault zones that cross-cut compositional layering. Numerical modelling studies on fault rupture nucleation, propagation and arrest often assume that the fault mechanical behaviour is governed by either the rheologically weak phase or by a homogeneous gouge mixture of juxtaposing lithologies. However, the effects of spatial heterogeneity on fault gouge composition and hence its frictional behaviour are less known. In this study, we simulate a mixture of mechanically contrasting rheologies of claystones and sandstones in fault gouges by using lithologies available in the well-known Groningen gas field stratigraphy (Ten Boer and Slochteren members, respectively). Friction experiments were performed in a rotary shear configuration to accommodate the large displacements required to study mixing and clay smearing in faults with large offsets. A velocity stepping procedure was conducted to quantify the rate-dependence of friction and its evolution with displacement. A spatial heterogeneity was introduced by segmentation of the simulated gouge in claystone and sandstone patches. In contrast to previous studies, we show that Slochteren sandstone gouges can exhibit velocity-weakening behaviour related to strain-localization in a principal slip zone with reduced grain size. Our experiments on segmented gouges show displacement-dependent changes in the sliding friction and its rate-dependence. Clay smearing and shear localization on foliation planes cause weakening of the gouge and a shift from velocity-weakening to velocity-strengthening behaviour. Progressive shearing leads to juxtaposition of sandstone segments that are separated only by a thin clay smear. We propose that the associated increase in friction is caused by lithology mixing at the interfaces between the clay smear and the bulk Slochteren sandstone gouge, and by the disruption of continuous Y-shears. Progressive shearing does not lead to a decrease in the

The structural evolution of the present-day Dutch offshore has been influenced by tectonic events coupled with halokinesis, eustatic changes and modifications in the rate of sediment supply. The research aims to disentangle the effects of these controlling factors in the Upper Jurassic – Early Cretaceous sediments of the Dutch Central Graben, by studying the tectonic-induced sedimentation at high resolution. It accounts for local tectonic and regional salt re-distribution features. The results show a better quantification of tectonic pulses that increases the resolution of the current broader tectonostratigraphic framework. Reconstruction involves first-order restorations based on local kinematics and available 3D-seismics. The syn-rift sedimentation of the Upper Jurassic Schieland Group marks the onset of basin development, followed by Scruff Group sedimentation encompassing basin margins and subsequent basin center uplift into turtle anticlines. The well log control enabled a facies model and a quantification in tectonic successions, resulting in a higher order subdivision of the tectono-stratigraphic framework of the Late Callovian – Late Oxfordian deformation into five higher resolution tectonic pulses. These pulses are reflected in terms of increased tectonic activity followed by its subsequent decrease, while the correlation with available sea-level curves shows that they are not influenced by eustatic changes. Furthermore, our research also shows that the successions observed in the earlier Scruff Group are controlled dominantly by eustasy, as 3rd order sea-level fluctuations coincide with the lower order sedimentary cycles observed in well log data and are not linked to rifting mechanics. Differences in local basin development of the two studied transects show that local factors influence the tectonostratigraphic evolution significantly. These main controlling factors are linked with the interplay between fault activation and salt-re-distribution, resulting

The structural evolution of the present-day Dutch offshore has been influenced by tectonic events coupled with halokinesis, eustatic changes and modifications in the rate of sediment supply. The research aims to disentangle the effects of these controlling factors in the Upper Jurassic – Early Cretaceous sediments of the Dutch Central Graben, by studying the tectonic-induced sedimentation at high resolution. It accounts for local tectonic and regional salt re-distribution features. The results show a better quantification of tectonic pulses that increases the resolution of the current broader tectonostratigraphic framework. Reconstruction involves first-order restorations based on local kinematics and available 3D-seismics. The syn-rift sedimentation of the Upper Jurassic Schieland Group marks the onset of basin development, followed by Scruff Group sedimentation encompassing basin margins and subsequent basin center uplift into turtle anticlines. The well log control enabled a facies model and a quantification in tectonic successions, resulting in a higher order subdivision of the tectono-stratigraphic framework of the Late Callovian – Late Oxfordian deformation into five higher resolution tectonic pulses. These pulses are reflected in terms of increased tectonic activity followed by its subsequent decrease, while the correlation with available sea-level curves shows that they are not influenced by eustatic changes. Furthermore, our research also shows that the successions observed in the earlier Scruff Group are controlled dominantly by eustasy, as 3rd order sea-level fluctuations coincide with the lower order sedimentary cycles observed in well log data and are not linked to rifting mechanics. Differences in local basin development of the two studied transects show that local factors influence the tectonostratigraphic evolution significantly. These main controlling factors are linked with the interplay between fault activation and salt-re-distribution, resulting

One key element in the current debate analysing the Central Mediterranean evolution is the Cretaceous structure and kinematics of the present-day oroclinal bent contact between Adria- and Europe-derived continental units in the Dinarides, interpreted in different tectonic reconstructions as a subduction-related thrust system or a large-scale strike-slip fault zone. We provide a solution to the debate by a structural and kinematic study in a key area located in central Serbia along the Europe–Adria orogenic suture of the Sava Zone. The results demonstrate that large-scale, top-SW, in- to out-of-sequence thrusting is the dominant mechanism that deformed the observed accretionary wedge-trench sediments during the Late Cretaceous subduction of the Neotethys Ocean and the ensuing Adria–Europe collision. The subsequent Oligocene–Miocene extension of the Pannonian Basin was associated with opposite-sense rotations of different Sava Zone segments, which created the observed ~80° oroclinal bending.