Multiple generations of pseudotachylyte in the Wenchuan fault zone and their implications for coseismic weakening
Multiple generations of pseudotachylyte in the Wenchuan fault zone and their implications for coseismic weakening
复制标题
汶川断裂带多代拟速成岩及其对同震减弱的意义
DOI：
10.1016/j.jsg.2015.03.007
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发表时间：
2015-05
影响因子：
3.1
通讯作者：
Si Jialiang
中科院分区：
文献类型：
--
作者：
Wang Huan;Li Haibing;Janssen Christoph;Sun Zhiming;Si Jialiang
假玄武玻璃通常被认为是过去地震的残留产物，传达了重要的信息，这为更好地了解断层行为及其力学性质提供了帮助。2008年汶川地震发生时，位于青藏高原东缘的映秀-北川断裂带沿着的彭关杂岩中出露了假玄武玻璃和碎裂岩。根据露头调查，假玄武玻璃岩脉为灰色、深灰色、棕色和黑色，厚度从几毫米到10厘米不等。通过光学显微镜和扫描电子显微镜的显微结构观察表明，不同的纹理，如球晶，微晶，蜂窝状囊泡结构，流动结构，不规则形状和深湾碎屑，存在于假玻璃体，表明假玻璃体确实是熔融起源。宏观和微观尺度上不同颜色的脉体及其叠加关系，表明映秀-北川断裂带沿着有多次地震断裂事件和伴生的假玄武玻璃。摩擦熔融润滑、热增压和机械润滑都可以在一次断层滑动运动中存在，表明多个断层弱化机制可能在一次同震事件中起作用。
Pseudotachylytes are generally considered to be remnent products of past earthquakes, conveying significant information, which provide improved insight into the fault behavior and their mechanical properties. Pseudotachylytes and cataclastic rocks are exposed in the Pengguan complex along the Yingxiu-Beichuan fault zone, which ruptured during the 2008 Wenchuan earthquake, at the eastern margin of the Tibetan Plateau in Sichuan province, China. From outcrop investigations, pseudotachylyte veins are gray, dark-gray, brown and black, with thicknesses ranging from several mm to ∼10 cm. Microstructural observations, via optical microscope and SEM, show that distinct textures, such as spherulites, microlites, honeycomb-like vesicle structures, flow textures, irregularly shaped and deep embayed clasts, are present in the pseudotachylytes, suggesting that the pseudotachylytes are indeed melt-origin. Different colored veins and their overprinting relations observed at both macroscopic and microscopic scales, demonstrate that seismic faulting events and the associated generations of pseudotachylyte occurred repeatedly along the Yingxiu-Beichuan fault zone. Friction melt lubrication, thermal pressurization and mechanical lubrication, all can exist during one fault slip motion, indicating that multiple fault weakening mechanisms may work during a single coseismic event.
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影响因子：
64.8
作者：
Di Toro, G;Goldsby, DL;Tullis, TE
通讯作者：
Tullis, TE
中国四川省汶川地震断层科学钻探项目Hole-1 (WFSD-1)的磁特性
影响因子：
3
作者：
Wang, Huan;Si, Jialiang;Sun, Zhiming;Zhou, Zaizheng
通讯作者：
Zhou, Zaizheng
DOI：
10.5860/choice.28-1579
发表时间：
2016
期刊：
--
影响因子：
--
作者：
Leon Bieber
通讯作者：
Leon Bieber
影响因子：
2.6
作者：
Q. Yan;A. Hanson;Zong-qi Wang;P. Druschke;Zhen Yan;Tao Wang;Dunyi Liu;B. Song;P. Jian;
通讯作者：
Q. Yan;A. Hanson;Zong-qi Wang;P. Druschke;Zhen Yan;Tao Wang;Dunyi Liu;B. Song;P. Jian;
影响因子：
2.9
作者：
J. Spray
通讯作者：
J. Spray