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"Wave" fields have long been recognized in marine sediments on the flanks of basins and oceans in both tectonically active and inactive environments. The origin of "waves" (hereafter called undulations) is controversial; competing models ascribe them to depositional processes, gravity-driven downslope creep or collapse, and/or tectonic shortening. Here we analyze pervasive undulation fields identified in swath bathymetry and new high-resolution multichannel seismic (MCS) reflection data from the Sea of Marmara, Turkey. Although they exhibit some of the classical features of sediment waves, the following distinctive characteristics exclude a purely depositional origin: (1) parallelism between the crests of the undulations and bathymet- ric contours over a wide range of orientations, (2) steep flanks of the undulations (up to ∼40°), and (3) increases in undulations amplitude with depth. We argue that the undulations are folds formed by gravity-driven downslope creep that have been augmented by depositional processes. These creep folds develop over long time periods (≥0.5 m.y.) and stand in contrast to geologically instantaneous collapse. Stratigraphic growth on the upslope limbs indicates that deposition contributes to the formation and upslope migration of the folds. The temporal and spatial evolution of the creep folds is clearly related to rapid tilting in this tectonically active transform basin. [ABSTRACT FROM AUTHOR]

Background: The February 6, 2023, twin earthquakes in Türkiye caused significant structural damage and a high number of injuries, particularly affecting the spine, which underscores the importance of understanding the distribution and nature of vertebral injuries in disaster victims., Aim: To investigate the distribution of radiological findings of vertebral injuries in patients referred to a major tertiary center during the February 6, 2023 twin earthquakes in Türkiye., Methods: With the approval of the institutional ethics committee, 1216 examinations of 238 patients transferred from the region to a tertiary major hospital after the twin earthquakes of February 6, 2023, were retrospectively analyzed for spine injuries., Results: Spine computed tomography (CT) scans were performed in 192 of 238 patients with a suspected spinal injury, 42 of whom also had an magnetic resonance imaging (MRI). In 86 of 192 patients (44.79%; M:F = 33:53) a spinal fracture was detected on CT and in 33 of 42 patients (78.57%; M:F = 20:13) a spinal injury was found on MRI. Of the 86 patients in whom vertebral injury was detected, fractures were detected in the Denis-B group in 33, Denis-C in 4, Denis-D in 20 and Denis-E in 11 patients. Among the vertebral bodies: 40 "compression fractures", 17 "burst fractures", 5 "translational dislocation fractures", 5 "flexion-distraction fractures" and 58 "prolonged forced fetal posture fractures" were detected. In addition, isolated transverse or spinous process fractures were found in eighteen vertebrae., Conclusion: Our study highlights the prevalence and diverse spectrum of spinal injuries following the February 6, 2023 twin earthquakes in Turkey underscoring the urgent need for effective management strategies in similar disaster scenarios, and emphasizing the "prolonged forced fetal posture" damage we encountered in earthquake victims who remained under the collapse for a long time., Competing Interests: Conflict-of-interest statement: There is no conflict of interest., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)