In the 2024 Noto Peninsula Earthquake, significant damage including building collapses, fires, landslides, and ground deformation due to liquefaction were caused, especially in Ishikawa and Toyama Prefectures, Japan. Collapse and some large displacement/deformation appear in not only the cultural stone walls in Kanazawa Castle, Nanao Castle as well as Maeda Toshinaga Masoleum, but also some large subsidence and collapse of slopes were observed in the Sakuradani Tomb, located in Takaoka City, Toyama Prefecture. The affected tombs were the 1st (62 m in length) and the 2nd Tombs (50 m in length) of Sakuradani Tombs are believed to be constructed as earthen mounds. The earthquake-induced damage to the tombs will be significantly related to the ground conditions and especially, the relation between the vibration characteristics and strong seismic motions will play significant roles. Although many microtremor measurements have been conducted and reported in previous studies, very few studies focus on the ground vibration characteristics of tombs constructed as earthen mounds. This study targeted Tomb 1 and Tomb 2 of Sakuradani Tomb, analyzing factors of earthquake-induced damage such as subsidence and ground cracks by comparing microtremor measurement results with strong ground motion data. The results suggest that the relationship between the acceleration Fourier spectra of strong ground motion and the H/V spectra of the surface ground and mound areas will be related to the occurrence of earthquake damage such as subsidence and cracks.
Hara et al. (Thu,) studied this question.