In Brazil, as in many countries, inventories of mass movements usually exist for specific events and on a watershed scale and are predominantly produced from visual interpretation of aerial or orbital images, and those produced using automatic and semiautomatic methods are incipient in the national context. One of these events, the Ribeira de Iguape River Valley (Southeast Brazil), was severely affected by mass movements between January 13 and 14, 2014. The objective of this article was to produce a semiautomatic inventory and perform a brief geomorphological evaluation. of the mass movements triggered. A TanDEM-X digital elevation model (DEM) (12 m) was used to extract the watersheds (area: 109.7 km²) most affected by mass movements and multispectral images of the RapidEye satellites, captured before (01-10-2014) and after (01-30-2014) the event. From the multispectral images, the pre-event and post-event NDVI and the difference between the NDVI on these two dates were computed. Using the angle map, contribution area and topographic wetness index (TWI), the map of affected areas was refined into two classes: deposits of debris flows and other hydrodynamic mass movements (slope angle <6°; TWI <14; and contribution area >50,000 m²) and scars from shallow landslides (slope angle >6°; TWI <14; contribution area <50,000 m²). Approximately 5% of the total area was affected by mass movements, with 1.44 km² of area corresponding to deposits of flows and other hydrodynamic mass movements and 4.04 km² of area corresponding to scars from landslides. In total, 2089 landslide scars were mapped. The most affected slopes had angles between 20° and 40°, a TWI less than 9.0 and a concave curvature in profile and in planform, and approximately 90% of the scars occurred in areas covered by dense vegetation (NDVI >0.80 on 01-10-2014). The results may contribute to the expansion of the application of automatic and semiautomatic methods for the detection of mass movement scars in Brazil in a systematic manner using open source software.

在巴西，与许多国家一样，大规模运动清单通常存在于特定事件和分水岭范围内，主要来自航空或轨道图像的视觉解释，而使用自动和半自动方法生成的那些在国家范围内处于初期阶段。其中一个事件是里贝拉德伊瓜佩河谷（巴西东南部），在 2014 年 1 月 13 日至 14 日期间受到大规模运动的严重影响。本文的目的是生成半自动清单并进行简短的地貌评估。引发的群众运动。TanDEM- X数字高程模型 (DEM) (12 m) 用于提取受质量运动影响最大的流域（面积：109.7 km ^{2 ）和多光谱图像}RapidEye卫星，在事件之前 (01-10-2014) 和之后 (01-30-2014) 捕获。根据多光谱图像，计算了事件前和事件后的 NDVI 以及这两个日期的 NDVI 之间的差异。使用角度图、贡献面积和地形湿度指数（TWI），将受影响区域的地图细化为两类：泥石流沉积物和其他水动力质量运动（坡角<6°；TWI<14；贡献面积> 50,000 m ²）和浅层滑坡的疤痕（坡度角>6°；TWI <14；贡献面积<50,000 m ²）。大约 5% 的总面积受到群众运动的影响，1.44 km ²对应于流动沉积物和其他流体动力质量运动的面积和对应于滑坡疤痕的面积为4.04 km ^{2 。}总共绘制了 2089 个滑坡疤痕。受影响最大的斜坡的角度在 20° 和 40° 之间，TWI 小于 9.0，剖面和平面呈凹曲率，大约 90% 的伤痕发生在植被茂密的区域（01-10 NDVI >0.80） -2014）。该结果可能有助于扩展自动和半自动方法的应用，以使用开源软件系统地检测巴西的群众运动疤痕。