講演情報
[P015A [発表前半]]Beyond Line-of-Sight Displacement: Integrating MT-DInSAR and operational records to interpret tailing storage facilities deformation regimes
○Sáncheza Vanessa1[博士課程]、Okada Natsuo1、Ohtomo Yoko1、Quispe Rafael2、Orozco Cristian2、Gallegos Sneyder2、Sebastián Morales2、Kawamura Youhei1 (1. Division of Sustainable Resources Engineering, Graduate School of Engineering, Hokkaido University、2. Institutional affiliation withheld due to confidentiality obligations under a non-disclosure agreement)
キーワード：
尾鉱貯蔵施設、変形監視、地理空間分析、リスク管理、運用段階
Multi-temporal Differential Interferometric Synthetic Aperture Radar (MT-DInSAR) is increasingly used for tailings storage facility (TSF) monitoring because it provides spatially continuous deformation measurements over large areas. However, deformation patterns in active TSFs should not be interpreted independently from operational conditions, since construction activity, tailings deposition, drainage changes, and staged embankment raising can strongly influence both the magnitude and direction of movement. This study presents an operationally contextualized analysis of MT-DInSAR deformation data for an active TSF, with emphasis on linking deformation regimes to construction and operational phases. Ascending and descending MT-DInSAR observations from 2020 to 2026 were decomposed into vertical and east–west deformation components. The decomposed time series were analyzed across key TSF sectors, including the crest, toe, embankment sectors, beach, and surrounding slopes, including a total of 208 points. Instead of classifying deformation only from cumulative displacement or velocity magnitude, deformation regimes were defined using component velocities, temporal acceleration, vertical-to-lateral deformation ratios, temporal persistence, and spatial coherence. These regimes were then compared with the construction plan and operational records to distinguish deformation responses associated with active construction from those occurring during periods without construction. The results show that deformation patterns vary substantially between TSF sectors and operational phases. Periods of active construction are associated with localized increases in vertical settlement and lateral movement, particularly near embankment and crest areas, while no-construction periods show more gradual deformation trends that may reflect consolidation, hydrological response, or progressive ground movement. The regime-based interpretation provides a clearer operational meaning than line-of-sight displacement alone, because it helps separate expected construction-related deformation from potentially persistent or anomalous movement. This work demonstrates that MT-DInSAR analysis for TSFs should be integrated with operational information rather than treated as an isolated remote-sensing product. The proposed approach supports more interpretable deformation monitoring by linking satellite-derived movement patterns to site activity, improving the value of MT-DInSAR for surveillance, risk screening, and operational decision support.