高雄縣小林村獻肚山巨型深層崩塌引致之地形變遷特性

The Geomorphological Variation Triggered by Catastrophic Deep Landslide in Siaolin Village

陳樹群(Su-Chin Chen) ； 吳俊鋐(Chun-Hung Wu)

《中華水土保持學報》 40卷4期 (2009/12) Pp. 359-376

https://doi.org/10.29417/JCSWC.200912_40(4).0005

摘要

本文主要針對高雄縣甲仙鄉小林村於2009年莫拉克颱風所引發之崩塌災害進行探討，主要分析內容爲崩塌前後之地形變遷量及地形特徵分析；地形變遷量以崩塌前及崩塌後之5m×5m數值高程模型進行估算，以此估算總崩塌量及總堆積量，並擷取縱及橫剖面方式分析崩塌前後之高程變化量，且經由崩塌後崖面高程分佈判斷崩塌類型；由地形變遷量分析上，獻肚山總崩塌面積約爲251.7公頃，本研究將崩塌區域區分爲A及B兩崩塌區，A崩塌區崩塌源頭面積約爲48.5公頃，此處平均崩塌深度約42.1公尺，總崩塌量約爲2551.2萬立方公尺，崩塌型態主要爲順向坡崩塌，爾後並轉爲土石流及土砂堆積；B崩塌區崩塌源頭面積約爲10.7公頃，此處平均崩塌深度約爲9.6公尺，總崩塌量約爲160.6萬立方公尺，崩塌型態仍以順向坡崩塌爲主，土砂主要堆積在靠近旗山溪河岸處；經本研究判斷崩塌主因應爲降雨引發水分入滲在糖恩山砂岩及上方堆積層間形成滑動面而引發大規模滑動。

關鍵字

小林村 ； 順向坡滑動 ； 崩塌深度 ； 崩塌量估算

並列摘要

The study focuses on the deep landslide caused by the rainfall during Typhoon Morakot in Siaolin Village, Kaohsiung County in 2009. The topographic variation and characteristic before and after the landslide are the main research topics in the study. The study used a 5m×5m Digital Elevation Model before and after Typhoon Morakot to calculate landslide volume. The elevations of the longitudinal and cross landslide profile before and after the landslide were calculated to analyze the types and characteristic of the landslide. The total landslide area, including landslide A and landslide B, in Mt. Xian-Tu is about 251.7 hectares. The landslide area and average landslide depth in the landslide source zone in landslide A are 48.5 hectares and 42.1 m, respectively. The total landslide volume in landslide A is about 2.55×10^7 m^3. The landslide type in landslide A is a dip-slope landslide. This becomes debris flow and sediment deposit in the down-slope. The landslide area and average landslide depth in the landslide source zone in landslide B are 10.7 hectares and 9.6m, respectively. The total landslide volume in landslide A is about 1.61×10^6 m^3. The landslide type in landslide B is also a dip-slope landslide, andsediment deposits near the river on the down-slope. The sliding plane caused by the infiltration during the rainfall is between the Tangenshan sandstone and deposit layer.

並列關鍵字

Siaolin Village ； Dip-slope landslide ； landslide depth ； landslide volume