4:45 PM - 5:00 PM
[HTT14-06] Comparative analysis on topographic measurement methods for active rocky slopes in Täschgufer, Switzerland
Rock sediments resulting from rockfalls and debris flows often accumulate on steep slopes under relatively unstable conditions. The surface structure of these rocks, including varying grain sizes can provide insights into the processes driving the mass movements. While low-altitude aerial photogrammetry is effective for capturing some detailed surface structures of rock sediments over large areas, assessing more complex three-dimensional structures requires closer-range measurements on ground. In this study, we employ mobile lidar and photogrammetry to conduct close-range measurements of rockfall and debris-flow-derived sediments, evaluating the efficiency and applicability of these methods for delineating detailed shape and structure through topographic analysis. It is expected that grain size, particularly along the vertical axis, can be effectively represented using mobile lidar and photogrammetry, while the primary limitation lies in the accessibility of steep, unstable slopes, which restricts wide-area coverage.