DC 欄位 | 值 | 語言 |
dc.contributor.author | 胡植慶 | zh_TW |
dc.creator | 胡植慶 | - |
dc.date | 2002 | zh_TW |
dc.date.accessioned | 2006-07-25T10:32:48Z | - |
dc.date.accessioned | 2018-06-28T12:49:41Z | - |
dc.date.available | 2006-07-25T10:32:48Z | - |
dc.date.available | 2018-06-28T12:49:41Z | - |
dc.date.issued | 2002 | - |
dc.identifier | 902116M002035 | zh_TW |
dc.identifier.uri | http://ntur.lib.ntu.edu.tw//handle/246246/11804 | - |
dc.description.abstract | 利用三維數值模式分析研究脆性變形中
常見之主應力軸交換的現象,在野外量測斷層
滑移及地震斷層機制解中常可從逆推的主應
力軸方向,觀測到上述之主應力軸交換之現
象。本研究之主要目的在於利用三維數值模式
建立主應力軸交換的力學模式,至於因間冰期
所產生之彈性回跳所造成之主應力軸交換則不在本研究範疇內。不管遠場的應力狀態,由因岩體流變性質
的改變造成應力值的改變足以更改局部的構
造應力分布而造成主應力軸交換,此主應力軸
交換並不是單純肇因於方向上的改變,而大部
分是肇因於主應力值的變化。此結果與自然界
之觀察頗為一致。雖然因應力軸方向的改變所
造成的主應力軸交換亦存在,但應力值的改變
卻是造成主應力σ1-σ2 或σ2-σ3 軸交換的主要因
素,此結果與脆性構造變形的觀察相吻合。值
得注意的是本研究的結果是在邊界條件中間
主應力值等於最大主應力值及最小主應力值和之平均(Φ值等於0.5 )下完成。一般而言,較低的Φ值較易造成σ2/σ3 軸交換,而較高的Φ值較易造成σ1/σ2 軸交換。以地質的特性而言,主應力軸交換的主要
因素在於脆性變形的異質性(如在斷層密部的
地塹變形帶中存在著較剛性的塊體)或是斷層
及斷裂作用所造成的力學性質的非均向性(如
岩體中平行斷層走向比其他方向更剛性),我
們的研究明確顯示力學性質的非均向性易於
造成主應力軸交換。因在自然界中變形帶常隨
著時間及空間而演變,因此主應力軸交換的現象非常普遍。 | zh_TW |
dc.description.abstract | Using 3-D distinct-element modeling, we
explore a variety of simulations to characterize
the stress permutations observed in brittle
tectonics. Stress inversions of fault slip data or
earthquake focal mechanisms often reveal such
permutations. The main aim of our study is to
produce mechanically consistent 3-D models that
account in a simple way for switches between
principal stress axes σ1-σ2 or σ2-σ3. Other
phenomena, such as those related to elastic
rebound, are beyond the scope of this work.
It appears that the stress changes induced
by variations in rheology are large enough to
modify the local tectonic behavior and produce
permutations of principal stress axes, despite the
simplicity of far-field boundary conditions.
Rather than simple directional changes, which
exist but are limited, the relative variations in
principal stress values are the major cause of
permutations σ1-σ2 and σ2-σ3. This is in good
agreement with observations in nature, where
despite permutations the orientations of axes
often remain tightly clustered. Note that the most
demonstrative experiments were done with a
ratio Φ of 0.5, implying that σ2 is the arithmetic
mean between σ1 and σ3 (low Φ ratios favor
σ2/σ3 permutations, whereas high Φ ratios favor
σ1/σ2 ones).
In terms of geological significance, we
conclude that the major causes of stress
permutations are the heterogeneity of the brittle
deformation (e.g., intact rock massifs between
heavily faulted grabens of deformation zones)and the anisotropy of the mechanical properties
that results from the fracturing and faulting (that
is, a rock more resistant in the direction parallel
to faults than in other directions). Our modeling
effectively revealed that anisotropy in rock
properties favor stress permutations. Of major
importance seems to be the existence of
relatively resistant zones at the tips of deformed
ones, acting as channels where stress
concentrates and switches occur. Because in
nature such zones move in time and space, it is
not surprising that stress permutations are so
pervasive.
In our modeling experiments, we explored a
variety of compressional, extensional and
strike-slip tectonic situations involving stress
permutations. | en |
dc.format | application/pdf | zh_TW |
dc.format.extent | 196609 bytes | - |
dc.format.mimetype | application/pdf | - |
dc.language | zh-TW | zh_TW |
dc.language.iso | zh_TW | - |
dc.publisher | 臺北市:國立臺灣大學地質科學系暨研究所 | zh_TW |
dc.rights | 國立臺灣大學地質科學系暨研究所 | zh_TW |
dc.subject | 數值模式 | zh_TW |
dc.subject | 脆性變形 | zh_TW |
dc.subject | 應力軸交換 | zh_TW |
dc.subject | 3-D numerical modeling | en |
dc.subject | brittle
tectonics | en |
dc.subject | stress permutations | en |
dc.title | 台灣及鄰近地區地殼變形之數值研究模式(III):應力軸轉換之三維數值模式分析 | zh_TW |
dc.type | report | en |
dc.identifier.uri.fulltext | http://ntur.lib.ntu.edu.tw/bitstream/246246/11804/1/902116M002035.pdf | - |
dc.coverage | 計畫年度:90;起迄日期:2001-08-01/2002-07-31 | zh_TW |
item.languageiso639-1 | zh_TW | - |
item.cerifentitytype | Publications | - |
item.fulltext | with fulltext | - |
item.openairecristype | http://purl.org/coar/resource_type/c_93fc | - |
item.openairetype | report | - |
item.grantfulltext | open | - |
crisitem.author.dept | Geosciences | - |
crisitem.author.dept | Center for Weather Climate and Disaster Research | - |
crisitem.author.orcid | 0000-0001-5044-5225 | - |
crisitem.author.parentorg | College of Science | - |
crisitem.author.parentorg | Others: University-Level Research Centers | - |
顯示於: | 地質科學系
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