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Transpressional margins are widespread, and their dynamics are relevant for plate boundary evolution globally. Though transpressional orogen evolution involves a topographic response to deformation, many studies focus only on the structural development of the system ignoring surface processes. Here, we present a new set of analog models constructed to investigate how tectonic and surface processes interact at transpressive plate boundaries and shape topography. Experiments are conducted by deforming a previously benchmarked crustal analog material in a meter‐scale plexiglass box while controlling erosion through misting nozzles mounted along the transpressional wedge. To analyze the experiments, we generate digital elevation models from laser scans and conduct image correlation analysis on photos taken during experiments. We focus on three experiments that cover a range of erosional conditions and shortening stages (two end‐member erosion models and a dry reference). In all experiments, a bivergent wedge forms, and strain partitioning broadly evolves according to previously established models. Regarding drainage networks, we find that the streams in our models develop differently through feedback between fault development and drainage rearrangement processes. Differences between end‐member erosional models can be explained by the varying response of streams to structure modulated by rainfall. Additionally, erosion may influence the structural evolution of transpressional topography, leading to accelerated strike‐slip partitioning. From these results, we create a model for developing structures, streams, and topography where incision and valley formation along main structures localize exhumation. We apply insights from the models to natural transpressional systems, including the Transverse Ranges, CA, and the Venezuelan Andes. Key Points: Feedback between fault and drainage network development regulates the deformation, exhumation, and morphology of transpressional systemsIncreased erosion accelerates the progression from distributed deformation to complete strike‐slip strain partitioningDue to heightened rock uplift and incision, the maximum exhumation in a transpressional wedge is along the master fault and axial valley [ABSTRACT FROM AUTHOR]

[1] Northern Victoria Land is located at the boundary between an extended, presumably hot, region (West Antarctic Rift System) and the thick, possibly cold, East Antarctic craton. The style and timing of Tertiary deformation along with relationships with the magmatic activity are still unclear, and contrasting models have been proposed. We performed structural and morphotectonic analyses at the NE termination of northern Victoria Land in the Admiralty Mountains area, where the relationship between topography, tectonics, and magmatism is expected to be well pronounced. We found evidence of two subsequent episodes of faulting, occurring concurrently with the Neogene McMurdo volcanism. The first episode is associated with dextral transtension, and it is overprinted by extensional tectonics during the emplacement of large shield alkaline volcanoes. Upper mantle seismic tomography shows that the extensional regime is limited to regions overlying a low-velocity anomaly. We interpret this anomaly to be of thermal origin, and have tested the role of large-scale upwelling on lithosphere deformation in the area. The results of this integrated analysis suggest that the morphotectonic setting of the region and the magmatism is likely the result of upwelling flow at the boundary between the cold cratonic and the hot stretched province (WARS), at work until recent time in this portion of the northern Victoria Land.