Yang Shun, Han Xin, Chang Chaoyu, Yu Sihan, Wang Yin, Peng Da
Earthquake Agency of Ningxia Hui Autonomous Region, Yinchuan, 750001, China.
Gansu Earthquake Agency, Lanzhou, 730000, China.
Sci Rep. 2025 Jul 2;15(1):22666. doi: 10.1038/s41598-025-08195-9.
The unique topographical and geomorphological characteristics of the southern Ningxia area, coupled with the active seismic activity background, have led to loess earthquake-induced landslides becoming the predominant type of seismic geological disaster in this region. Among them, the landslides triggered by the 1920 Haiyuan M8.5 great earthquake are particularly typical and severe. This study is based on the detailed data of 600 loess earthquake-induced landslides within the study area obtained from field investigations, and provides a detailed and in-depth summary of the distribution characteristics of loess earthquake-induced landslides in the Ningnan area. The results show that the landslides in this area have typical characteristics such as gentle slope gradient of the developed slope, large scale of landslides, long sliding distance, wide disaster impact range, and strong group occurrence. Further analysis reveals that the spatial distribution of landslides is mainly influenced by the comprehensive effects of seismic motion intensity, loess cover thickness, type of fault rupture, and hydrological conditions. Based on the loess landslide geometric parameter database in southern Ningxia, this study applies a binary logistic regression model to successfully establish a rapid evaluation formula for the seismic stability of loess slopes in the study area. The discriminant accuracy of this formula can reach more than 95%, providing an efficient and accurate method for the seismic stability evaluation of loess slopes. On this basis, in combination with the geological model database of loess slopes in the study area, the rapid evaluation formula for the seismic stability of loess slopes is used to systematically evaluate the seismic stability of loess slopes in the study area under different seismic motion intensities, and finally six loess earthquake-induced landslide hazard zoning maps of the Ningnan area under different estimated seismic motion intensities are compiled. The research results of this paper not only enrich the theoretical system of seismic geological disaster research in the Ningnan area, but also provide a strong decision-making reference for the prevention and response strategy formulation of earthquake-induced landslide disasters in practical applications.
宁夏南部地区独特的地形地貌特征，加之活跃的地震活动背景，导致黄土地震滑坡成为该地区主要的地震地质灾害类型。其中，1920年海原8.5级大地震触发的滑坡尤为典型和严重。本研究基于野外调查获取的研究区内600处黄土地震滑坡的详细数据，对宁南地区黄土地震滑坡的分布特征进行了详细深入的总结。结果表明，该地区滑坡具有发育斜坡坡度平缓、滑坡规模大、滑动距离长、灾害影响范围广、成群发育特征明显等典型特征。进一步分析发现，滑坡的空间分布主要受地震动强度、黄土覆盖厚度、断层破裂类型及水文条件等综合作用影响。基于宁夏南部黄土滑坡几何参数数据库，本研究应用二元逻辑回归模型成功建立了研究区黄土斜坡地震稳定性快速评价公式。该公式判别准确率可达95%以上，为黄土斜坡地震稳定性评价提供了一种高效准确的方法。在此基础上，结合研究区黄土斜坡地质模型数据库，利用黄土斜坡地震稳定性快速评价公式系统评价了研究区不同地震动强度下黄土斜坡的地震稳定性，最终编制了宁南地区不同预估地震动强度下的6幅黄土地震滑坡灾害分区图。本文的研究成果不仅丰富了宁南地区地震地质灾害研究的理论体系，而且在实际应用中为地震滑坡灾害的防治及应对策略制定提供了有力的决策参考。
