Assessment of geological hazards triggered by the 2024 Mw 7.4 earthquake in Hualien,Taiwan,China
On April 3,2024,an Mw 7.4 earthquake struck Hualien County in Tai wan,China,to trigger a number of extensive geological hazards in the mountainous areas of the region that led to a large number of casualties and significant economic losses.The rapid and accurate assessment of the spatial distribution of earthquake-induced geological hazards is crucial for post-earthquake emergency response and resettlement decisions.In this study,we leverage the Taiwan co-seismic landslide database and artificial intelligence algorithms to established a near-real-time model to predict the spatial distribution of earthquake-induced landslides.The proposed model can generate predictions of the occurrence of landslides within an hour of an earthquake.We mapped landslides by using automatic detection and visually interpreted them in an earthquake-affected region over five days based on synthetic aperture radar images from Sentinel-1A and optical images from the PlanetScope satellites.We used these data to interpret 876 co-seismic landslides over an area of 12.6 km2,primarily in high mountain gorges on the eastern side of the Central Mountain Range.The area under the curve(AUC)of predictions by the proposed model was 90%,which proves its accuracy and reliability.Our model can be used to provide timely and accurate data support for earthquake relief measures.