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Results from analogue inversion experiments of extensional basins parallel and oblique to their boundaries with inferences from the European eastern Southern Alps

This image dataset contains results (original top-view and cross-section photographs) obtained from a series of 12 crustal-scale physical analogue modelling experiments performed in the Tectonic Modelling Laboratory (TecLab) at Utrecht University. We employed analogue modelling to study the inversion of extensional basins that are parallel and oblique to their boundaries. The key parameters of this study are: (i) the obliquity angle (0°, 10° or 20°) of shortening in relation to the strike of the initial rift structures; (ii) the basal décollement rheology; and (iii) the rheology of the basin fill. All analogue experiments are rectangular, 2 cm thick and consist of deformable brittle or brittle–ductile layers. Deformable parts in entirely brittle models are made of a homogeneous layer of quartz sand for the initial, non-stretched, pre-rift model crust. The subsequently resulting grabens are filled with syn- to post-extensional sediments of quartz sand, feldspar sand, or glass beads. Variations to these setups entail either a brittle layer of glass beads at the base of the above described brittle crust, or, for brittle-ductile models, a viscous layer of PDMS silicone putty with fillers. All experiments are built on one fixed above two mobile plastic sheets, their transition is pre-defining velocity discontinuities (VDs). In a first stage, deformation is induced in all models by two electric motors pulling the two mobile plastic sheets in opposite directions parallel to the backstop. These sheets are then fixed once the extensional phase is finished. VDs positioned both orthogonally and obliquely with respect to the backstop allow graben structures to form at angles of 0°, 10° and 20° to the subsequent shortening direction. In a second stage, a rigid backstop moves into the model to create compressive deformation within the entirely brittle or brittle-ductile layers. Top-view photographs were taken at regular time intervals throughout each experiment (see below for details). Cross-section photographs were taken at the end of each experiment. Therefore, the top-view photographs enable surface deformation to be tracked and analysed through time and space, while the cross-sections demonstrate the overall vertical deformation of each model. For more details about the models, see Sieberer et al. (2023). The properties of the materials used are described in Sieberer et al. (2023), Klinkmüller et al. (2016) and Willingshofer et al. (2018). All models are scaled according to the principles of geometric, rheological, and kinematic similarity between nature and models (Hubbert, 1937; Weijermars & Schmeling, 1986).

Results from analogue inversion experiments of inherited structures controlling deformation and uplift with implications for the European eastern Southern Alps

This image dataset contains results (original top-view and cross-section photographs) obtained from a series of 4 crustal-scale physical analogue modelling experiments performed in the Tectonic Modelling Laboratory (TecLab) at Utrecht University. The experiments have been designed to allow comparison with the European eastern Southern Alps but are also relevant for other regions where lateral mechanical and structural heterogeneities within fold-and-thrust belts of inverted rift structures occur. Key features of our experiments include: (i) a predefined basin and platform configuration following Sieberer et al. (2023) and representing the result of Triassic to Jurassic rifting, (ii) a platform with lateral strength variations representing compositional heterogeneity related to Permian igneous activity and (iii) a basal plate representing an inherited basement structure. All analogue experiments are rectangular, maximum 2.0 cm thick, and are made of deformable layers only, except for Model 4 where a rigid basal plate is partly incorporated. The deformable part of all models is made of one homogeneous layer of dry quartz sand for the pre-defined post-rift model crust. The pre-defined platform and basin geometry yields lateral strength differences controlled by differences in layer thickness, with thinner (1.4 cm) compartments simulating overall weaker, rifted basin domains (e.g., alternations of limestone, marl, clay) compared to the thicker (1.8 to 2.0 cm) platform succession, simulating continental upper crust (e.g., basement rocks, carbonate platforms, volcanic rocks). All experiments are built on a table and on top of a fixed plastic sheet of 0.05 cm thickness and are shortened orthogonal to the backstop at a rate of 3 cm/h. We decided for simple orthogonal inversion models with shortening parallel to the axis of the eastern platform. Top-view photographs were taken at regular time intervals throughout each experiment (see below for details). Cross-section photographs were taken at the end of each experiment. Therefore, the top-view photographs enable surface deformation to be tracked and analysed through time and space, while the cross-sections demonstrate the overall vertical deformation of each model. For more details about the models, see Sieberer et al. (2025). The properties of the materials used are described in Sieberer et al. (2025) and Willingshofer et al. (2018). All models are scaled according to the principles of geometric, rheological, and kinematic similarity between nature and models (Hubbert, 1937; Weijermars & Schmeling, 1986).

Overviews and videos of top view imagery, topography data and DIC analysis results from analogue models of basin inversion

This data set includes videos depicting the surface evolution (time-lapse photography, topography data and Digital Image Correlation [DIC] analysis) of 11 analogue models, divided in three model series (A, B and C), simulating rifting and subsequent inversion tectonics. In these models we test how orthogonal or oblique extension, followed by either orthogonal or oblique compression, as well as syn-rift sedimentation, influenced the reactivation of rift structures and the development of new inversion structures. We compare these models with an intracontinental inverted basin in NE Brazil (Araripe Basin). All experiments were performed at the Tectonic Modelling Laboratory of the University of Bern (UB). We used an experimental set-up involving two long mobile sidewalls, two rubber sidewalls (fixed between the mobile walls, closing the short model ends), and a mobile and a fixed base plate. We positioned a 5 cm high block consisting of an intercalation of foam (1 cm thick) and Plexiglas (0.5 cm thick) bars on the top of the base plates. Then we added layers of viscous and brittle analogue materials representing the ductile and brittle lower and upper crust in our experiments, which were 3 cm and 6 cm thick, respectively. A seed made of the same viscous material was positioned at the base of the brittle layer, in order to localize the formation of an initial graben in our models. The standard model deformation rate was 20 mm/h, over a duration of 2 hours for a total of 40 mm of divergence, followed by 2 hours of convergence at the same rate (except for Models B3 and C3, since the oblique rifting did not create space for 40 mm of orthogonal inversion). For syn-rift sedimentation, we applied an intercalation of feldspar and quartz sand in the graben. Model parameters and detailed description of model set-up are summarized in Table 1, and results and their interpretation can be found in Richetti et al. (2023).

Digital image correlation data and orthophotos from lithospheric-scale analogue experiments of orthogonal extension followed by shortening

This dataset includes the results of 5 lithospheric-scale, brittle-ductile analogue experiments of extension and subsequent shortening performed at the Geodynamic Modelling Laboratory at Monash University (Melbourne, Australia). Here we investigated (1) the influence of the mechanical stratification of the model layers on rift basins during extension and (2) the influence of these basins on shortening-related structures. This dataset consists of images and movies that illustrate the evolution of topography (i.e., model surface height) and cumulative and incremental axial strain during the experiments. Topography and strain measures were obtained using digital image correlation (DIC) which was applied to sequential images of the model surface. This dataset also includes orthophotos (i.e., orthorectified images) of the model surface, overlain with fault traces and basins that were interpreted using QGIS. The experiments are described in detail in Samsu et al. (submitted to Solid Earth), to which this dataset is supplementary.

Slide-Hold-Slide Data of Granular Materials Used In Analogue Modelling

This data set provides a series of experiments from ring-shear tests (RST) on various materials that are used at several laboratories worldwide. The data contains the results of slide-hold-slide tests and the processed outputs of standardized ring shear tester data from related publications. Additionally, microscopy images of the materials under plain and polarized light are provided. The time dependent restrengthening of the materials is quantified using slide-hold-slide tests. This restrengthening has implications on the reactivation potential of granular shear zones in analogue models. With the provided software we first analyze the experimental data and then compare the angles and stresses needed to reactivate normal faults in the materials. We find that while healing rates are low, the majority of samples can not reactivate normal faults that are generated through extension of an analogue model.

Experimental data of analogue models addressing the influence of crustal strength, tectonic inheritance and stretching/ shortening rates on crustal deformation and basin reactivation

This dataset includes video sequences and strain analysis of 12 analogue models studying crustal-scale deformation and basin reactivation, performed at the Laboratory of Tectonic modelling of the University of Rennes 1. These models show how parameters such as crustal strength, tectonic inheritance and boundary conditions (ishortening/ stretching) control both the distribution of crustal strain and the possibility for pre-existing structures to be reactivated. This dataset includes top-view movies of the 12 models, including strain analysis based on displacement vectors obtained from digital image correlation. Detailed descriptions of models can be found in Guillaume et al. (2022, special issue of Solid Earth on Analogue modelling of basin inversion) to which this dataset is supplementary.