GFZ German Research Centre for Geosciences, Telegrafenberg, 14473, Potsdam, Germany.
Institute of Photogrammetry and GeoInformation, Leibniz University Hannover, Nienburger Str. 1, 30167, Hannover, Germany.
Sci Rep. 2021 Apr 8;11(1):7704. doi: 10.1038/s41598-021-87033-0.
Ground subsidence caused by natural or anthropogenic processes affects major urban areas worldwide. Sinkhole formation and infrastructure fractures have intensified in the federal capital of Maceió (Alagoas, Brazil) since early 2018, forcing authorities to relocate affected residents and place buildings under demolition. In this study, we present a 16-year history (2004-2020) of surface displacement, which shows precursory deformations in 2004-2005, reaching a maximum cumulative subsidence of approximately 200 cm near the Mundaú Lagoon coast in November 2020. By integrating the displacement observations with numerical source modelling, we suggest that extensive subsidence can be primarily associated with the removal of localized, deep-seated material at the location and depth where salt is mined. We discuss the accelerating subsidence rates, influence of severe precipitation events on the aforementioned geological instability, and related hazards. This study suggests that feedback destabilization mechanisms may arise in evaporite systems due to anthropogenic activities, fostering enhanced and complex superficial ground deformation.
自然或人为过程引起的地面沉降影响着全球各大城市。自 2018 年初以来，巴西阿拉戈斯州首府马塞约市（Maceió）的天坑形成和基础设施裂缝问题日益加剧，迫使当局将受影响的居民迁移，并将建筑物拆除。在本研究中，我们呈现了 16 年（2004-2020 年）的地表位移历史，显示 2004-2005 年出现了前兆变形，2020 年 11 月，在蒙达乌泻湖（Mundaú Lagoon）海岸附近达到了约 200 厘米的最大累积沉降量。通过将位移观测与数值源模型相结合，我们认为广泛的沉降主要与盐矿位置和深度处局部深层物质的移除有关。我们讨论了加速沉降率、严重降水事件对上述地质不稳定的影响以及相关的危害。本研究表明，由于人为活动，蒸发盐系统可能会出现反馈失稳机制，从而导致更强烈和复杂的地表变形。
