利用線形地震網探討台灣南部主要構造; A Study of Major Structures beneath Southern Taiwan by a Linear Seismic Array

NCUIR > College of Earth Sciences > Graduate Institute of Geophysics > Electronic Thesis & Dissertation > Item 987654321/5456

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/5456

Title:	利用線形地震網探討台灣南部主要構造;A Study of Major Structures beneath Southern Taiwan by a Linear Seismic Array
Authors:	蒲新杰;Hsin-Chieh Pu
Contributors:	地球物理研究所
Keywords:	波線追跡;潮州斷層;地震定位;視速度;粒子運動;隱沒帶;斷層帶;fault zone;Chao-Chou fault;subduction zone;locate;apparent velocity;particle motion;ray tracing
Date:	2003-06-09
Issue Date:	2009-09-22 09:54:23 (UTC+8)
Publisher:	國立中央大學圖書館
Abstract:	由於台灣位在歐亞大陸板塊和菲律賓海板塊的交界上，受到板塊相互間的作用，產生了許多的地體構造。本研究利用線形地震網的資料建立出台灣南部的地下構造。主要討論的構造有二個，一是位在台灣東南部的板塊隱沒帶，二是把中央山脈南段和屏東平原分隔開的潮州斷層。本研究之資料來源是由中央研究院地球科學研究所，在屏東地區設置之臨時地震網的記錄。此外，還包含了中央氣象局的地震資料。本研究使用了一些方法對潮州斷層和板塊隱沒帶進行討論。主要的方法是從波形資料中找尋一些特殊的遲達波相進行波線追跡，對這些遲達波相的波傳走時以正演（Forward）方式，建立最終的二維速度構造。除波線追跡之外，本研究還做了一些微震定位來討論潮州斷層的活動性、計算視速度差異來討論潮州斷層的二維速度構造剖面、粒子運動模式改變來討論潮州斷層的構造特性。本論文的結論分成三個部分，一是潮州斷層附近有眾多的微震活動，其斷層深度應該向下延伸到15 km以上，且斷層在地表面可能有約2 km寬的斷層帶存在；二是針對特殊遲達波相的走時分析，本研究清楚繪出了在台灣東南部的板塊隱沒帶二維速度構造；三是氣象局定位結果與雙網（氣象局短週期地震網與中研院臨時地震網）共同定位結果的比較，發現氣象局在台灣南部的地震定位有向更深部修正的趨勢。 Taiwan is located at a part of the convergent boundary between the Eurasian and Philippine Sea plates. A lot of geotectonic problems are have been created by the convergent plates. In this study, the seismic data recorded by a linear seismic array has been used to construct subsurface structures of the southern Taiwan. Two major structures have been focused. One is the subduction zone beneath the southeastern Taiwan. The other is the Chao-Chou fault that separates the Central range and pingtung plain. Seismic data used in this study were recorded at the seismic array in the Pingtung area, which was installed by IES (Institute of Earth Sciences, Academia Sinica). Seismic data collected by the CWB (Central Weather Bureau) are also included. Several seismological methods have been employed to discuss the features of both the Chao-Chou fault and the subduction zone in the southern Taiwan area. The main method of this study is the ray tracing of some particular later phases from the waveform data, which were recorded at the linear seismic array. The final two-dimensional velocity model was obtained through a detail forward modeling of travel times for these later phases. In addition to ray tracing, this study locates micro-earthquakes for discussing the seismic active of in and around the Chao-Chou fault, calculate apparent velocities for discussing the lateral two-dimensional velocity structure, and examine particle motion for discussing the characters about the Chao-Chou fault. This study can divide the conclusions into three parts. First, This study locates a lot of micro-earthquakes in and around the Chou-Chao fault. This fault is extended down to the depth of 15 km with a fault zone of about 2 km in width near the surface. Second, travel-time analyses of some particular later phases show that the subduction zone beneath the soueastern Taiwan area can be clearly described by the two-dimensional velocity structures. Finally, comparison of earthquakes reported by CWB with those relocated in this study indicates the location of earthquakes in and around here by CWB maybe move deeper.
Appears in Collections:	[Graduate Institute of Geophysics] Electronic Thesis & Dissertation

Files in This Item:

File	Size	Format

社群 sharing

Loading...