2017 Fiscal Year Research-status Report
A new method by exploring responses of mountain slopes to river incision for predicting potential landslide sites for hazard mitigation: A case of Shirakami-Sanchi, Japan
| Project/Area Number |
16K20893
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| Research Institution | Hirosaki University |
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Principal Investigator |
鄒 青穎 弘前大学, 農学生命科学部, 助教 (40750055)
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| Project Period (FY) |
2016-04-01 – 2019-03-31
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| Keywords | Landslide dynamics / Shirakami Mountains / River erosion |
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| Outline of Annual Research Achievements |
This study documents landslide occurrences of landslides align on the terrace scarp. The computed horizontal displacements range from 0.1 to 9.7m. The longitudinal displacement for a flat topography within the landslide was computed of ~7m that is represented as compared with the filed measurement. Active displacements were at the secondary and side scarps (3-9m) and the edges of toes (2-8m). The landslides were retreated by lateral river erosion based on the interpretation of changes of river courses and an outcrop exposed on the toe that consist of imbricated horizontally bedded gravels.
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| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
In FY 2017, study area was selected in the Okawa River, in which is comparatively accessible for field survey. To constrain the landslide occurrences (ca. 10 years),
a digital surface model (DSM) from UAV imagery was constructed using structure-from-motion (SfM) photogrammetric procedures. Then, the DSM was used to compare to an airborne LiDAR-derived digital elevation model (DEM) of 1-m resolution to constrain the landslide magnitude and direction of the displacement vectors using CIAS (the Correlation Image Analysis Software; Kaab and Vollmer, 2000). Besides, the changes of river courses were analyzed by aerial photos in different ages and field surveys were also conducted. These procedures are found that are useful and effective to understand the landslide dynamics.
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| Strategy for Future Research Activity |
The case study as mentioned above will be summarized for submission to a journal. Another case study within different geological setting will also be proceeded.
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| Causes of Carryover |
As mentioned in last time, I was planned to purchased satellite imagery and the LiDAR DEM for the study. However, aerial photos, which made with higher resolution than the satellite imagery, are free available for the study. Besides, UAV-derived photos are also used instead of the satellite imagery. The LiDAR DEM covered the study is provide by the Geospatial Information Authority of Japan and the Ministry of Land, Infrastructure, Transportation and Tourism, Japan.
The incurring amount will be used for purchase the survey equipment and software required for the future study.
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Research Products
(1 results)
