Seismogenic stress field beneath the Tatun Volcano Group, northern Taiwan

NCU Institutional Repository > 地球科學學院 > 地球物理研究所 > 期刊論文 > Item 987654321/27558

請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/27558

題名:	Seismogenic stress field beneath the Tatun Volcano Group, northern Taiwan
作者:	Konstantinou,KI;Lin,CH;Liang,WT;Chan,YC
貢獻者:	地球物理研究所
關鍵詞:	FOCAL MECHANISM DATA;LOCAL EARTHQUAKES;TENSOR ANALYSIS;CALIFORNIA;ANISOTROPY;FAULT;AREA;ALASKA;ERUPTIONS;LOCATION
日期:	2009
上傳時間:	2010-06-29 18:40:53 (UTC+8)
出版者:	中央大學
摘要:	The Tatun Volcano Group (TVG) represents the main volcanic center in northern Taiwan and based on various observations it is considered a potentially active volcano. TVG has been monitored since 2003 by a seismic network that consists of eight stations equipped with three-component, short-period and broadband seismometers. In this study, we use waveform data of high frequency earthquakes in order to investigate the stress field orientation beneath the TVG area. The focal mechanisms of 35 selected events have been derived using P-wave polarities and amplitude ratios, assuming a double-couple source. These fault plane solutions and various subsamples derived from them, were subsequently inverted for the best fitting stress tensor using a linear inversion method. The results show stress homogeneity beneath TVG for depths larger than 3 km while the stress tensor is characterized by a subvertical sigma(1) and a subhorizontal NW-SE trending sigma(3) axis consistent with the regional stress field in northern Taiwan. On the other hand, Chihsinshan which is an area of vigorous hydrothermal activity, exhibits a localized stress field with horizontal NW-SE trending sigma(3) axis and NE-SW trending horizontal sigma(1). Such an axes orientation is likely to be causing opening of microcracks and thus favour the ascent and circulation of fluids in the upper crust. Shear wave splitting measurements seem to confirm these results, showing fast polarization directions along NNE-NE, subparallel to the main fracture system in TVG. Shear wave anisotropy averages about 2.9% and is probably caused by an anisotropic volume of fluid-saturated cracks within the upper 2.5 km of the crust. (c) 2009 Elsevier B.V. All rights reserved.
關聯:	JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH
顯示於類別:	[地球物理研究所] 期刊論文

文件中的檔案:

檔案	描述	大小	格式	瀏覽次數
index.html		0Kb	HTML	409	檢視/開啟

在NCUIR中所有的資料項目都受到原著作權保護.

社群 sharing

資料載入中.....