Understanding Earth surface responses in terms of sediment dynamics to climatic variability and tectonics forcing is hindered by limited ability of current models to simulate long-term evolution of sediment transfer and associated morphological changes. This paper presents pyBadlands, an open-source python-based framework which computes over geological time (1) sediment transport from landmasses to coasts, (2) reworking of marine sediments by longshore currents and (3) development of coral reef systems. pyBadlands is cross-platform, distributed under the GPLv3 license and available on GitHub (http://github.com/badlands-model). Here, we describe the underlying physical assumptions behind the simulated processes and the main options already available in the numerical framework. Along with the source code, a list of hands-on examples is provided that illustrates the model capabilities. In addition, pre and post-processing classes have been built and are accessible as a companion toolbox which comprises a series of workflows to efficiently build, quantify and explore simulation input and output files. While the framework has been primarily designed for research, its simplicity of use and portability makes it a great tool for teaching purposes.

Dynamic topography due to mantle flow contributes to shaping Earth's evolving landscapes by affecting sediment routing, which has rarely been explored in source‐to‐sink contexts. Here we design a generic model to investigate the impact of dynamic topography on both landscape evolution and stratigraphic formations. An imposed wave of dynamic topography propagates laterally under a fixed continent, exerting transient surface uplift and subsidence. We find that a migrating dynamic topography can induce significant drainage reorganizations and affect sediment routing from source to sink. Variations in sediment supply driven by the lateral migrating dynamic topography contribute to the formation of diachronous unconformities along the margin. The predicted sediment flux histories are then put into perspective with the Cretaceous sedimentary records along the Southern African margins. Finally, we demonstrate that correlating offshore depositional hiatuses and unconformities has the potential to constrain the spatiotemporal evolution of past dynamic topography events.

Understanding the effects of climatic variability on sediment dynamics is hindered by limited ability of current models to simulate long-term evolution of sediment transfer from source to sink and associated morphological changes. We present a new approach based on a reduced-complexity model which computes over geological time: sediment transport from landmasses to coasts, reworking of marine sediments by longshore currents, and development of coral reef systems. Our framework links together the main sedimentary processes driving mixed siliciclastic-carbonate system dynamics. It offers a methodology for objective and quantitative sediment fate estimations over regional and millennial time-scales. A simulation of the Holocene evolution of the Great Barrier Reef shows: (1) how high sediment loads from catchments erosion prevented coral growth during the early transgression phase and favoured sediment gravity-flows in the deepest parts of the northern region basin floor (prior to 8 ka before present (BP)); (2) how the fine balance between climate, sea-level, and margin physiography enabled coral reefs to thrive under limited shelf sedimentation rates after ~6 ka BP; and, (3) how since 3 ka BP, with the decrease of accommodation space, reduced of vertical growth led to the lateral extension of reefs consistent with available observational data.

The sedimentary architecture at continental margins reflects the interplay between the rate of change of accommodation creation (δA) and the rate of change of sediment supply (δS). Stratigraphic interpretation increasingly focuses on understanding the link between deposition patterns and changes in δA∕δS, with an attempt to reconstruct the contributing factors. Here, we use the landscape modelling code pyBadlands to (1) investigate the development of stratigraphic sequences in a source-to-sink context; (2) assess the respective performance of two well-established stratigraphic interpretation techniques: the trajectory analysis method and the accommodation succession method; and (3) propose quantitative stratigraphic interpretations based on those two techniques. In contrast to most stratigraphic forward models (SFMs), pyBadlands provides self-consistent sediment supply to basin margins as it simulates erosion, sediment transport and deposition in a source-to-sink context. We present a generic case of landscape evolution that takes into account periodic sea level variations and passive margin thermal subsidence over 30 million years, under uniform rainfall. A set of post-processing tools are provided to analyse the predicted stratigraphic architecture. We first reconstruct the temporal evolution of the depositional cycles and identify key stratigraphic surfaces based on observations of stratal geometries and facies relationships, which we use for comparison to stratigraphic interpretations. We then apply both the trajectory analysis and the accommodation succession methods to manually map key stratigraphic surfaces and define sequence units on the final model output. Finally, we calculate shoreline and shelf-edge trajectories, the temporal evolution of changes in relative sea level (proxy for δA) and sedimentation rate (proxy for δS) at the shoreline, and automatically produce stratigraphic interpretations. Our results suggest that the analysis of the presented model is more robust with the accommodation succession method than with the trajectory analysis method. Stratigraphic analysis based on manually extracted shoreline and shelf-edge trajectory requires calibrations of time-dependent processes such as thermal subsidence or additional constraints from stratal terminations to obtain reliable interpretations. The 3-D stratigraphic analysis of the presented model reveals small lateral variations of sequence formations. Our work provides an efficient and flexible quantitative sequence stratigraphic framework to evaluate the main drivers (climate, sea level and tectonics) controlling sedimentary architectures and investigate their respective roles in sedimentary basin development.

Complex relationships exist between rationales for visiting, experiences and perceptions. Tourists are influenced by others, increasingly through social media as electronic word of mouth (ewom). While visitation rationales associated with popular culture are well documented, less understood is how social media use among specific cultural groups constructs and fuels new fictitious sites of popular cultural tourism, through what we call ‘soft heritage’. Particular physical qualities (often visual) endow places with a distinct but fabricated heritage value, linked especially to fictional characters in popular culture. Tourism numbers grow accordingly, as soft heritage sites become marked places for tourists of specific cultural backgrounds. This is illustrated through the case of the University of Sydney, which in the 2010s became a significant destination for Chinese tourists. Through mixed-methods research involving participant observation and interviews with 85 Chinese tourists, the rationales, experiences and perceptions of Chinese tourists were explored. Reasons for visiting included group tours, education, heritage and photography, but a key attraction was the ‘Harry Potter building’, a site not in JK Rowling’s books, nor involved in the making of the films, and not previously a tourist attraction. So much did social media and the Harry Potter Building influence tourism that the University became the most prominent of the city’s several ‘marked places’ (daka). The participatory character of Chinese social media, combined with architectural heritage and the enthusiasm of many younger Chinese tourists for Harry Potter, led them to create a new Chinese tourist site (or daka destination) without input from the management of the place itself.

Subduction of bathymetric anomalies (e.g., an active ridge) can alter the morphology of subducted slabs and their coupling to surface processes. A natural laboratory to study these effects is the subduction of the Oceanic Chilean Ridge beneath the South American plate, which led to the formation of the Patagonian slab window. Its formation and subsequent northward migration contributed to the regression of Patagoniense sea and exhumation of marine strata to their present elevation. To date, there is no quantitative analysis of the effects on the sediment routing system of the slab window. We modeled the Neogene topographic change and foreland sedimentary evolution from the Andean Cordillera to Atlantic margin. Our results show that subcrustal‐driven subsidence correlated with accelerated subduction of the Nazca plate is required to explain the timing of the Patagonian transgression and thickness and spatial extent of marine beds during the incursion. In other words, traditional mechanisms, such as foreland flexure and global sea‐level rise, are insufficient. The subsequent regression and accumulation of mid‐Miocene alluvial‐fluvial deposits were associated with the growth of the Cordillera and a possible flattening of Nazca subduction in the middle Miocene. Isostatic uplift of ∼1 km due to lithospheric thinning during slab window formation can explain the foreland exhumation, sediment bypass, and increases in the offshore sedimentation rate. However, spatial‐temporal varying dynamic uplift is required to explain the along‐strike variations in foreland sedimentation. Our study provides new insights into the interplay between slab window formation, crustal deformation, and landscape evolution.