學術資源整合系統-相關推薦

 
作者Chung, Ling-Ho;Chen, I-Min;Lee, Xin-He;Chiang, Cheng-Shing;Tsai, Chia-Hsin
出版日期20200116
著作名稱Regulation and conditioning of the trench walls preserved for exhibition in the Chelungpu Fault Park
會議論文集Hokudan 2020
會議地點日本,淡路島
會議日期20200114
國際性會議Y
其他資訊 https://home.hiroshima-u.ac.jp/kojiok/hokudan2020.html
主題地質
關鍵字集集地震; 車籠埔斷層
摘要The Chelungpu Fault Preservation Park is one of the most important sites for recording the Chi-Chi earthquake during 1999/9/21. According to research, five paleoseismic events were recorded in this trench. Because of the reverse fault behavior, about 1-2 m uplifting from each seismic event, the depth of the trench is over 8 meters which is the deepest preserved fault trench in the world. This causes greatly risk of slope collapse in this trench. Since 2013, four large-scale collapses have occurred. Fortunately, those collapses were appeared at the footwall side of the north wall and didn’t affect the display of the trench. However, the small collapse of 2017/6/27 (~ 1.6m * ~ 1m area) was happened near the Chelungpu fault line.
After the fifth collapse, five and two 4m-deep wells were set at the north and the south walls respectively. Moreover, the highest groundwater record was shown only ~0.5m below the surface. Compared with rainfall record, those five collapsing events were all come with the torrential rain events of the previous month, and the fifth collapse was occurred after 398 mm of the single-day rainfall at 2017/6/3. However, the regular range of groundwater level is 7-12m below the surface. We suggested that a shallow (about 3-4 m in depth) horizontal impermeable layer exist in the north wall, which was easily accumulated groundwater and formed a perched aquifer after heavy rain events.
Nowadays, pumping system was established to deal with the perched aquifer near the trench. During 2 weeks after the fifth collapsing, ~1.5 metric ton water was discharged from the pumping system. After 2-year observation, we have better understanding about the relation between groundwater and collapse. We ensure that the trench can continue to be used for earthquake education.
系統號NO000005868

Aug 20 2021 11:12:17
nmns/nmnsweb_2nd_target(0)