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).