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The data set includes the Digital Image Correlation (DIC) results for four experiments of releasing bends along dextral strike-slip faults that were performed at the University of Massachusetts at Amherst (USA). Gabriel et al. (in prep.) used the DIC data sets to investigate how releasing bend fault systems evolve within different strength wet kaolin. Information on the experimental set up and methods can be found in the main text and supplement to Gabriel et al. (in prep.). The data here include the incremental displacement time series, strain animation and surface elevation data at the end of the two experiments with different clay strength, which are presented within Gabriel et al. (in prep). We also include in this data repository incremental displacement time series and strain animations from two experiments that repeat the conditions of the experiments featured in Gabriel et al. (2025). 

Abstract Subduction zones are host to some of the largest and most devastating geohazards on Earth. The magnitude of these hazards is often measured by the amount of energy they release over short periods of time, which itself depends on how much stored energy is available for the geologic processes that drive these hazards. By considering the energy transfer among processes within subduction zones, we can identify the energy inputs and outputs to the system and estimate the stored energy. Due to the multiscale nature of subduction zone processes, developing an energy budget of subduction zone hazards requires integrating a wide range of geologic and geophysical field, laboratory, and modeling studies. We present a framework for developing mechanical energy budgets of upper crustal deformation that considers processes within the magmatic system, at the subduction zone interface, distributed and localized deformation between the arc and trench, and surface processes that erode, transport, and store sediments. The subduction energy budget framework provides a way to integrate data and model results to explore interactions between diverse processes. Because fault mechanics, sediment transport and magmatic processes within subduction zones do not act in isolation, we gain insights by considering the common energetic elements of the subduction zone system. Building energy budgets reveals gaps in our understanding of subduction zone processes, and thus highlights opportunities for new interdisciplinary research on subduction zone processes that can inform hazard potential. 

Releasing bends along active strike-slip faults display a range of fault patterns that may depend on crustal strength. Scaled physical experiments allow us to directly document the evolution of established releasing bend systems under differing strength conditions. Here, we use a split-box apparatus filled with wet clay of differing strengths to run and analyze releasing bend evolution. Precut vertical discontinuities within the clay slip with right-lateral displacement of the basal plate followed by the development of oblique-slip secondary faults. In contrast to the weaker clay experiment, which produces left-lateral cross faults that facilitate major reorganization of the primary slip pathway, the stronger clay experiment produces negligible cross faults and has a persistent primary slip pathway. Within both experiments, the dip of initially vertical faults shallows due to lateral flow at depth and left-lateral slip develops along normal fault segments that have highly oblique strike. The experiments show that fault systems within weaker strength materials produce greater delocalization of faulting, with both greater number of faults and greater off-fault deformation that can impact hazard. For example, the hot, thin and weak crust hosting the Brawley Seismic Zone accommodates slip along many distributed faults, which is in sharp contrast to the more localized fault network of the Southern Gar Basin in cooler, thicker and stronger crust. The fault patterns observed in the experiments match patterns of crustal examples and may guide future models of fault evolution within relatively strong and weak crust that have differing heat flux and thickness. 

Recent field studies provide evidence of fault slip-rate variability over time periods of 10–100 k.y., yet researchers do not know how processes internal to the fault system (e.g., fault reorganization) impact records of fault slip rates. In this study, we directly observed fault-system evolution and measured slip-rate histories within a scaled physical experiment of a dextral strike-slip 15° restraining bend representative of a gentle crustal restraining bend. To assess the degree of slip-rate variability at particular sites along the experimental faults, such as would be revealed in a field study, we tracked fault slip rates at specific locations that advected throughout the experiment with accrued fault slip. Slip rates increased or decreased (5%–25% of the applied velocity) both during fault reorganization (e.g., fault growth and abandonment) and as sites migrated to new structural positions. Sites that advected into the restraining bend showed decreased slip rate. While we expect new fault growth to reduce slip rates along nearby fault segments, we document that the growth of new oblique-slip faults can increase strike-slip rates on nearby fault segments. New oblique-slip thrust faults within the experiment accommodated off-fault convergence and unclamped nearby strike-slip segments. The experimental results show that even under a constant loading rate, slip rates at sites located on stable fault segments can vary due to either reorganization elsewhere in the fault system or site advection. 

Abstract Field geologists are increasingly using unmanned aerial vehicles (UAVs or drones), although their use involves significant cognitive challenges for which geologists are not well trained. On the basis of surveying the user community and documenting experts’ use in the field, we identified five major problems, most of which are aligned with well-documented limits on cognitive performance. First, the images being sent from the UAV portray the landscape from multiple different view directions. Second, even with a constant view direction, the ability to move the UAV or zoom the camera lens results in rapid changes in visual scale. Third, the images from the UAVs are displayed too quickly for users, even experts, to assimilate efficiently. Fourth, it is relatively easy to get lost when flying, particularly if the user is unfamiliar with the area or with UAV use. Fifth, physical limitations on flight time are a source of stress, which renders the operator less effective. Many of the strategies currently employed by field geologists, such as postprocessing and photogrammetry, can reduce these problems. We summarize the cognitive science basis for these issues and provide some new strategies that are designed to overcome these limitations and promote more effective UAV use in the field. The goal is to make UAV-based geological interpretations in the field possible by recognizing and reducing cognitive load. 

We demonstrate the effectiveness of straightforward strategies using widely available auto-captioning tools to greatly improve accessibility of jargon-rich content.