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A digital outcrop example and associated structural analysis of highly deformed sedimentary strata from the Zagros Belt of Iran is presented. By providing this site in open-access, downloadable format, we aim to make this excellent outcrop exposure accessible to a wide range of geoscientists. Digital data extraction techniques are used to constrain structural interpretations and cross section orientation, as well as kinematic restorations of interpreted structures. Structural analysis protocols provided here are well-suited to learning outcomes associated with digital cross section construction, interpretation and restoration. Complex deformation at the study locality and associated uncertainties in horizon and fault mapping yield interpretation and structural restoration results that are likely non-unique. Interpretation uncertainties are discussed in the context of geoscience education, with specific reference to the need for considering and assessing data quality and underlying geological assumptions. Our workflow and results can be used to bridge the gap between field-based training at undergraduate level and the proficiency in 3D digital environments required of professional geoscientists. By using digital outcrops to achieve learning outcomes, knowledge of underlying geological processes and practical skills in digital data handling and treatment can be effectively communicated to future geoscientists within the virtual environment. • Excellent exposure from the Zagros Belt of Iran reconstructed using digital photogrammetry. • Digital measurements used for structural analysis and to constrain structural interpretations and kinematic restoration. • Complex deformation at the site results in non-unique structural interpretations which we suggest can be used to communicate geological uncertainty. • Digital outcrop-based teaching can bridge the gap between field-based skills and proficiency in digital environments. [ABSTRACT FROM AUTHOR]

Coastal exposures of Carboniferous-age strata in SW Wales are recognised for their excellent preservation of Variscan deformation. The classic fold-thrust outcrop at Broadhaven, Pembrokeshire, is a particularly well-known example, and an oft-cited 'type example' of fault-related folding, following work by Williams & Chapman (1983). The outcrop has been important for generating conceptual models of fault-fold interaction, and was one of the sites where distance-displacement data were first used to infer thrust slip/propagation ratios. Here we employ the virtual outcrop method to digitally map and measure this classic locality. 3D reconstruction of the outcrop by digital photogrammetry allows us to extract high-density structural measurements, reassess the existing model of structural development, and re-evaluate the link between faulting and folding at the site. We find that high-resolution digital measurements record greater variability in thrust displacement and bed thicknesses than previously documented at the site. Distance-displacement data record the influence of mechanical anisotropy on slip/propagation ratios through the deformed multilayer. Bed thickness changes are linked to this variability in thrust displacement, highlighting transitions in strain accommodation patterns. Fracture analysis shows that fracture intensity is closely linked to structural position and bed thickness changes, and that fracture orientations record the existence of discrete mechanical boundaries through the structure. These results record complex patterns of strain distribution and multi-phase deformation. Evidence for temporal and spatial variability in strain distribution suggests that multiple kinematic and non-kinematic models of deformation are required to faithfully describe even this apparently simple structure. We use this detailed field evidence to propose an alternative to and develop, for multi-layered stratigraphy, the ductile bead model of Elliot (1976), as exemplified at Broadhaven by Williams & Chapman (1983).ReferencesElliott, D., 1976. The motion of thrust sheets. Journal of Geophysical Research, 81(5), pp.949-963.Williams, G. and Chapman, T., 1983. Strains developed in the hangingwalls of thrusts due to their slip/propagation rate: a dislocation model. Journal of Structural Geology, 5(6), pp.563-571. [ABSTRACT FROM AUTHOR]