台北盆地構造及震波速度分析; Tertiary Basement Structures and S-wave Velocities Analysis of the Taipei Basin, Taiwan

NCUIR > College of Earth Sciences > Graduate Institute of Geophysics > Electronic Thesis & Dissertation > Item 987654321/5481

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/5481

Title:	台北盆地構造及震波速度分析;Tertiary Basement Structures and S-wave Velocities Analysis of the Taipei Basin, Taiwan
Authors:	陳怡伶;Yi-Ling Chen
Contributors:	地球物理研究所
Keywords:	震波速度分析;台北盆地;Taipei Basin;Wave velocity
Date:	2004-06-15
Issue Date:	2009-09-22 09:54:54 (UTC+8)
Publisher:	國立中央大學圖書館
Abstract:	近年來各項研究皆指出，當地震波經過台北盆地鬆軟的沖積盆地時會造成盆地內震波的場址放大效應，因此都會區的防災工作成為一個值得深入研究的課題。本研究的目的在測繪整個台北盆地的三維地下構造形貌，並且將影響建築物較大的S波資料做一有系統的整理分析，尤其著重於表層松山層的速度分佈，這些構造及速度資料為進一步研究台北盆地都會區防災所需，可提供各界使用。本研究結合震測資料以及地調所近年來大量鑽探深井的結果，進而將地下第三紀基盤面形貌以及松山層S波速度的描繪更加完善。本研究有下列幾項發現：（1）盆地基盤面最深處應在淡水河出口處，即為在盆地的西北角；（2）坎腳斷層可視為一個分離邊界，將台北盆地畫分為基盤較深的西北部以及基盤較淺的東南部兩部分；(3)在盆地西北邊基盤的形狀暗示著山腳斷層可能有部分穿透到大屯火山底下；(4)淺層的S波波速約有兩個低區，分別為盆地西北邊較深處以及盆地的東南邊緣機場附近。(5)淺層的松山層厚度大概50-120公尺且此層的沉積結構很軟弱，具有非常低速的S波波速(120-350m/sec)，景美層S波速為450 m/sec，基盤S波波速則估計為1000m/sec。 Taipei city, the capital of Taiwan, is located in the Taipei basin. The thick recent deposits in this ‘soft’ basin have caused significant earthquake damage due to site amplifications, although the earthquakes have mostly occurred outside the basin. The top near-surface layer, called the Sungshan formation, is thought to carry the burden of the site-effects, because of its loose sand and silt content. Over the past 10 years, the Central Geological Survey has conducted a wide-range of investigations of the Taipei basin by drilling over 30 wells (100-700m). During the same period, we have also scanned the basin area (20x20 km) using over 300 shallow reflection seismic lines. The purpose of this paper is to compile these seismic data, incorporating it with the borehole drilling results, to better describe the Tertiary basement, the Quaternary layers above the basement and their P- and S-wave velocities. It is found that 1) the deepest part of the basin basement is probably at the outlet of the Tanshui river, i.e., at the NW corner of the basin, 2) the Kanchiao fault forms a separation boundary bisecting the basin into a deep NW part and a shallow SE part, 3) the sharp of the basement implies the Sanchiao fault may be long enough to penetrate under the Tatun volcanic region in the north. 4) there are two low-velocity area in the, the NW and SE corner of the basin, 5) the depth of the Sungshan formation from 50 to 120 meter and the S-wave velocity is about 120~350m/sec. The S-wave velocity of the Chingmei formation is 450m, and the S-wave velocity of the basement is 1000m/sec.
Appears in Collections:	[Graduate Institute of Geophysics] Electronic Thesis & Dissertation

Files in This Item:

File	Size	Format

社群 sharing

Loading...