| 06 Jul 2026
Long-term evolution and type-specific rainy-season activity of post-seismic geohazards in Southwest China
Abstract. Long-term evolution of post-seismic geohazards represents a critical yet complex challenge in earthquake-affected regions. This study systematically investigates the spatiotemporal patterns of post-seismic geohazard evolution following three major seismic events: the 2008 Wenchuan earthquake (Mw7.9), 2013 Lushan earthquake (Mw6.6), and 2017 Jiuzhaigou earthquake (Mw7.0), focusing on four representative counties (Wenchuan, Beichuan, Lushan, and Jiuzhaigou County) in Southwest China. The results show that: (1) post-seismic geohazard activity showed an intermittent clustered outbreak pattern; (2) geohazards were mainly concentrated in valley-related geomorphic units, with county-level differences characterized by reactivation–expansion, spatial inheritance, localization, and contraction; (3) monthly records excluding earthquake-month records showed a clear rainy-season concentration, with 78.1 % of geohazards occurring from June to August; and (4) Beichuan and Lushan showed clearer weakening trends, whereas Wenchuan and Jiuzhaigou remained in low-level persistent activity stages and should receive continued monitoring attention. These findings provide useful insights for long-term geohazard monitoring and risk mitigation in earthquake-affected mountainous regions.
The manuscript addresses essentially technical, scientific, and probabilistic issues, which are integral to the topics covered by NHESS. The study examines the long-term evolution and seasonal patterns of post-seismic geohazards in the mountainous regions of western Sichuan, China. It focuses on four counties (Wenchuan, Beichuan, Lushan, and Jiuzhaigou) affected by three major earthquakes (Wenchuan 2008, Lushan 2013, Jiuzhaigou 2017). The study, which covers the geological and geomorphological context of China, can, however, be considered a model for internationally applicable research. The research findings, data, and maps reported in the paper may encourage fellow scientists to experiment with this research methodology elsewhere in the world, especially in seismically active areas affected by potentially destructive earthquakes, capable of also impacting slope stability. Therefore, the conclusions are substantial. The title clearly reflects the content of the document, the abstract is complete and provides consistent information about the study, which is intended for a broader, non-specialist audience, also taking into account the implications for civil protection. The size and readability of the figures are sufficiently relevant and appropriate to the data presented. The authors give due credit to previous work, spanning a sufficient period of time. In this regard, both the number and quality of references are appropriate, and the references are accessible for use by other researchers. The overall presentation is well-structured, clear, and easy to understand, especially for technicians and scientists in the field. The length of the paper is adequate and balanced for an international scientific context. The technical language is precise and understandable even by other researchers thanks to the use of good-quality English, which is fluent, simple, and easy to read and understand, even by a broad and diverse audience. The document is not accompanied by supplementary material.
Given its characteristics, the paper can be accepted without modification, but if the authors deem it appropriate, they could enrich the manuscript with: