Repository logo
  • English
  • 中文
Log In
Have you forgotten your password?
  1. Home
  2. College of Science / 理學院
  3. Geography / 地理環境資源學系
  4. On the Taipei Dammed Lake
 
  • Details

On the Taipei Dammed Lake

Resource
地理學報, 36, 077-100
Journal
地理學報
Journal Issue
36
Pages
077-100
Date Issued
2004-06
Date
2004-06
Author(s)
鄧屬予  
李錫堤
劉平妹
宋聖榮  
曹恕中
劉桓吉
彭志雄
URI
http://ntur.lib.ntu.edu.tw/bitstream/246246/281532/1/0036_200406_4.pdf
Abstract
To test the hypothesis that the Taipei Basin was a lake dammed from a coastal bay by the volcanic rocks at Kuandu, we examined the boreholes of the Taipei Basin and found in the shallow subsurface a widespread estuarine deposit indicative of the alleged coastal bay. This deposit, however, extends into the Tanshui estuary west of Kuandu and is neither overlain by any lacustrine deposit nor by volcanics. Instead, it overlies the volcanic rocks at Kuandu, indicating that the Tanshui river channel postdates the volcanics. These features demonstrate that the Basin has not been dammed by volcanics since the bay was formed, and thus the early hypothesis is invalid. The genuine dammed-lake event is recorded in the deep subsurface of the Taipei Basin as shown by a widely distributed laminated mud and associated lahar. The laminated mud is mostly embedded in the fluvial deposits, but in the northwestern part of the Basin, it is underlain by a north-thickening lahar that connects with the Tatun volcanoes. This stratigraphic relationship strongly suggests that the lahar derived from the Tatun volcanoes was responsible for damming the Taipei Basin. Because the areas west of the shangjiao Fault and east of Beitou show no signs of channel blocking, Fushinggang remains the only potential site for lahar damming. The damming took place at 180 ka and the lake lasted till 160 ka based on the integrated stratigaphic and radiochronol logical data. Before the damming, the Tanshui River Flowed north from the Taipei Basin through Fushinggang into the Tatun volcanic area. At around 180 ka, fierce volcanic eruption in the Tatun area spewed voluminous lahars into the Tanshui River valley and blocked the effluent channel. Soon the Tanshui River flooded the Taipei Basin and turned it into a freshwater lake. As the lake expanded and deepened, the lake water eventually spilled over the basement high at Kuandu and cut a new channel between Kuandu and Tanshui. The channel progressively eroded headward and undermined the basement dike at Kuandu. At 160 ka, the dike collapsed, the lake drained, and the Basin returned to a floodplain environment. If the Tanshui River had indeed passed through the Tatun volcanic area before the Taipei Basin was dammed, most of the Tatun volcanoes that presently stand more than 500 m high should not have existed before 180 ka. This age estimate is significantly younger than those exhibited by radiometric data of the Tatun volcanics, which calls for reassessment of the eruption history of the Tatun volcanoes. The dammed-lake event demonstrates that Tatun volcanism is capable of causing catastrophic flooding in the Taipei metropolitan area if the Tanshui River is blocked.This potential hazard, which has been overlooked in the past, needs to be carefully evaluated in the future.
Subjects
堰塞湖
臺北盆地
大屯火山
自然災害
第四紀
Dammed lake
Taipei basin
Tatun volcanoes
Natural hazard
Quaternary
Type
journal article
File(s)
Loading...
Thumbnail Image
Name

0036_200406_4.pdf

Size

554.19 KB

Format

Adobe PDF

Checksum

(MD5):9f4a932cb2bdc72fe081a7e8a32297d8

臺大位居世界頂尖大學之列,為永久珍藏及向國際展現本校豐碩的研究成果及學術能量,圖書館整合機構典藏(NTUR)與學術庫(AH)不同功能平台,成為臺大學術典藏NTU scholars。期能整合研究能量、促進交流合作、保存學術產出、推廣研究成果。

To permanently archive and promote researcher profiles and scholarly works, Library integrates the services of “NTU Repository” with “Academic Hub” to form NTU Scholars.

總館學科館員 (Main Library)
醫學圖書館學科館員 (Medical Library)
社會科學院辜振甫紀念圖書館學科館員 (Social Sciences Library)

開放取用是從使用者角度提升資訊取用性的社會運動,應用在學術研究上是透過將研究著作公開供使用者自由取閱,以促進學術傳播及因應期刊訂購費用逐年攀升。同時可加速研究發展、提升研究影響力,NTU Scholars即為本校的開放取用典藏(OA Archive)平台。(點選深入了解OA)

  • 請確認所上傳的全文是原創的內容,若該文件包含部分內容的版權非匯入者所有,或由第三方贊助與合作完成,請確認該版權所有者及第三方同意提供此授權。
    Please represent that the submission is your original work, and that you have the right to grant the rights to upload.
  • 若欲上傳已出版的全文電子檔,可使用Open policy finder網站查詢,以確認出版單位之版權政策。
    Please use Open policy finder to find a summary of permissions that are normally given as part of each publisher's copyright transfer agreement.
  • 網站簡介 (Quickstart Guide)
  • 使用手冊 (Instruction Manual)
  • 線上預約服務 (Booking Service)
  • 方案一:臺灣大學計算機中心帳號登入
    (With C&INC Email Account)
  • 方案二:ORCID帳號登入 (With ORCID)
  • 方案一:定期更新ORCID者,以ID匯入 (Search for identifier (ORCID))
  • 方案二:自行建檔 (Default mode Submission)
  • 方案三:學科館員協助匯入 (Email worklist to subject librarians)

Built with DSpace-CRIS software - Extension maintained and optimized by 4Science