921集集大地震誘發大山崩與形成堰塞湖災害初步調查

The Premier Investigation on Landslide and Landslide Dam after Chi-Chi Earthquake in Central Taiwan

蔡光榮(Kuang-Jung Tsai) ； 王弘祐(Hung-Yu Wang) ； 林金炳(Jing-Bing Ln) ； 侯峻棕(Chun-Tzung Hou) ； 林昆賢(Kuen-Shian Lin)

《地工技術》 77期 (2000/02) Pp. 93-100

https://doi.org/10.30140/SG.200002.0006

摘要

1999年9月21日凌晨1時47分於台灣中部地區南投縣日月潭西偏南12.5公里處發生芮氏地震規模達7.3之強烈地震，誘發大茅埔～雙冬斷層產生錯移，進而觸動車籠埔斷層發生劇烈錯動位移，致使此二南北走向斷層所經之處樓倒村毀、天崩地裂與人亡財失，造成極為嚴重災害，而斷層帶沿線之各項公共工程設施、高樓民宅、維生管線、道路橋樑、水利設施、農糧設備、古蹟建築、交通建設、水庫埧工、水土保持工程等相關政府與民間工程均因受此二斷層錯動而產生巨大地表垂直與水平位移，而深受重創，已非短期內即可復原。國內外專家學者為配合政府救災行動和災後重建工作之推動，並積極防患二次災害之發生和其可能衍生災區範圍之擴大而加重災情。故本文乃對集水區治理、崩塌地處理與災害治理等各項相關治山防災工作，先行以災後航照地形和衛星影像作初步研判，並建立災區之基本GIS圖層，再以GPS作實地現況初步調查，俾期取得災情背景資料，予以彙整分析，提供後續災後重建工作推動之參考。

關鍵字

集集地震 ； 地震工程 ； 山崩 ； 堰塞湖

並列摘要

The Chi-Chi earthquake occcurred at September 21 early morning (1:47AM) in 1999. The epienter was located at 12.5 Km far from the west of Sun-Moon Lake, Chi-Chi, Nantou county. It has been recognized as a serious disaster caused by Chi-Chi earthquake. The Damges of public consturction, agricultural facilities, humman activities supporting networks and transportation systems have been identfied and investigated by using aerophotography and satellite image processing technology. 2365 landslide spots have been identified by the aerophotography technology. The stability of dam-forming landslide located at Nantou county proved to be critical and important in the disaster area. The volume of impoundment was estimated to be 35*10^6 m^3 in total area of 698 ha. In fact, the most common initiation mechanisms for dam-forming landslide are excessive rainfall, snow melt and earthquake. However, most landslide dams are remarkably short lived. The landslide daming of rivers in Nantou county has proved to be a significant hazard in the near future. The main purpose of this premier investigations is to collect all informations which can give a reference for the stabliization of landslide and landslide dam afer Chi-Chi earthquake.

並列關鍵字

chi-chi earthquake ； earthquake engineering ； landslide ； landslide dam