Due to challenges involved in mapping the seafloor at high‐resolution (e.g., <2 m), data are lacking to understand processes that control the evolution of submarine normal fault scarps, which cover large parts of the global seafloor. Here, we use data from autonomous deep‐sea vehicles to quantify local erosion and deposition associated with a pronounced tectonic surface scarp formed by slip on the submarine Roseau normal fault (Lesser Antilles). We use high‐resolution video imagery, photomosaics, and high‐resolution bathymetric data (0.1–10 m/pixel) to identify active erosional features on the scarp including channels, steep gullies, small scarps, and debris cones. We compare volumes of erosion and deposition and find that under certain depositional conditions, debris cones effectively record the erosion signal of mass wasting from the footwall with a ratio of hanging wall deposition to footwall erosion of 0.80. We use eroded volumes to estimate earthquake‐induced landslide erosion rates for the Roseau fault of 14–46 m Myr⁻¹. Assuming mass wasting of the Roseau fault scarp is mostly coseismic, the erosion rates for the Roseau fault imply that submarine earthquake induced mass‐wasting can occur at similar rates to various terrestrial lithological and tectonic settings. We present a process‐based model of submarine scarp degradation via retrogressive erosion in basement lithology where scarps have a gravitational stability threshold height of 20–40 m and a long‐term average slope of 30°–40°. More generally, the results presented here may be applicable to develop models of submarine landscape evolution based on degradation of normal fault scarps on the seafloor.

中文翻译：

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重力质量浪费的定量分析和沿罗索断层（安的列斯群岛）的海底鲤鱼形态的控制

由于以高分辨率（例如，<2 m）对海底进行地图绘制所涉及的挑战，因此缺乏数据来了解控制海底正常断层带演化的过程，该过程覆盖了全球大部分海底。在这里，我们使用来自自主深海飞行器的数据来量化与水下Roseau正常断层（Lesser Antilles）滑动形成的明显构造表面陡峭有关的局部侵蚀和沉积。我们使用高分辨率的视频图像，光马赛克和高分辨率的测深数据（0.1–10 m /像素）来识别出陡峭的主动侵蚀特征，包括通道，陡峭的沟壑，小陡峭的陡坡和碎屑锥。我们比较了侵​​蚀和沉积的量，发现在某些沉积条件下，碎屑锥有效地记录了来自后壁的质量浪费的腐蚀信号，其中悬挂壁沉积与下壁腐蚀的比率为0.80。我们使用侵蚀量来估算14-46 m Myr罗索断层的地震诱发滑坡侵蚀速率^-1。假设Roseau断层断层的大量浪费是同震的，那么Roseau断层的侵蚀速率意味着海底地震引起的大量浪费可以以与各种陆地岩性和构造环境相似的速率发生。我们提出了一种基于过程的海底陡坡退化过程，该模型是通过地下岩性中的渐进侵蚀进行的退化，其中陡坡的重力稳定性阈值高度为20–40 m，长期平均斜度为30°–40°。更一般而言，此处显示的结果可能适用于基于海底正常断层陡坡的退化开发海底景观演化模型。