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Abstract Oceanic plates experience extensive normal faulting as they bend and subduct, enabling fracturing of the incoming lithosphere. Debate remains about the relative importance of pre‐existing faults, plate curvature and other factors controlling the extent and style of bending‐related faulting. The subduction zone off the Alaska Peninsula is an ideal place to investigate controls on bending faulting as the orientation of the abyssal‐hill fabric with respect to the trench and plate curvature vary along the margin. Here, we characterize faulting between longitudes 161°W and 155°W using newly collected multibeam bathymetry data. We also use a compilation of seismic reflection data to constrain patterns of sediment thickness on the incoming plate. Although sediment thickness increases over 1 km from 156°W to 160°W, most sediments were deposited prior to the onset of bending faulting and thus should have limited impact on the expression of bend‐related fault strikes and throws in bathymetry data. Where magnetic anomalies trend subparallel to the trench (<30°) west of ∼156°W, bending faults parallel magnetic anomalies, implying that bending faults reactivate pre‐existing structures. Where magnetic anomalies are highly oblique (>30°) to the trench east of 156°W, no bending faults are observed. Summed fault throws increase to the west, including where pre‐existing structure orientations are constant (between 157 and 161°W), suggesting that another factor such as the increase in slab curvature must influence bending faulting. However, the westward increase in summed fault throws is more abrupt than expected for gradual changes in slab bending alone, suggesting potential feedbacks between pre‐existing structures, slab dip, and faulting. 

Abstract Sample return capsules (SRCs) entering Earth’s atmosphere at hypervelocity from interplanetary space are a valuable resource for studying meteor phenomena. The 2023 September 24 arrival of the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer SRC provided an unprecedented chance for geophysical observations of a well-characterized source with known parameters, including timing and trajectory. A collaborative effort involving researchers from 16 institutions executed a carefully planned geophysical observational campaign at strategically chosen locations, deploying over 400 ground-based sensors encompassing infrasound, seismic, distributed acoustic sensing, and Global Positioning System technologies. Additionally, balloons equipped with infrasound sensors were launched to capture signals at higher altitudes. This campaign (the largest of its kind so far) yielded a wealth of invaluable data anticipated to fuel scientific inquiry for years to come. The success of the observational campaign is evidenced by the near-universal detection of signals across instruments, both proximal and distal. This paper presents a comprehensive overview of the collective scientific effort, field deployment, and preliminary findings. The early findings have the potential to inform future space missions and terrestrial campaigns, contributing to our understanding of meteoroid interactions with planetary atmospheres. Furthermore, the data set collected during this campaign will improve entry and propagation models and augment the study of atmospheric dynamics and shock phenomena generated by meteoroids and similar sources.