Recrystallization of quartz after low-temperature plasticity – The record of stress relaxation below the seismogenic zone
Recrystallization of quartz after low-temperature plasticity – The record of stress relaxation below the seismogenic zone
复制标题
石英低温塑性后的再结晶 â 震源带以下应力松弛的记录
DOI：
10.1016/j.jsg.2016.12.004
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发表时间：
2017
影响因子：
3.1
通讯作者：
Wichmann
中科院分区：
文献类型：
--
作者：
Trepmann;Hentschel;Döhler;Schneider;Wichmann
利用偏振光和电子显微镜对东阿尔卑斯Silvretta基底逆冲构造和deferegen - antholz - vals （DAV）剪切带岩石中的石英微组构进行了分析。来自两个剪切带的微组构记录了在绿片岩相条件下，从瞬态高应力下的低温塑性到松弛应力下的再结晶的转变。新晶粒的形成主要是在低温塑性初期形成的局部高应变区进行亚晶旋转和随后的应变诱导晶界迁移。研究结果表明，新晶粒在应力弛豫速率快（即在低应力下）的情况下以几乎随机的晶体取向发育，如Silvretta断裂带中的再结晶石英带所示。相反，在缓慢的应力松弛速率下，新晶粒在中等高应力下发育，具有晶体学上的优先取向，其特征是基底滑动的高施密德因子，如来自DAV剪切带的脉状石英样品所示。记录的瞬态峰值应力和不同应力松弛率的历史都被解释为与断层系统的地震活动有关。研究表明，特征微组构提供了不同构造条件下自然剪切带变形史的重要信息。
Quartz microfabrics in rocks from the Silvretta basal thrust and the Defereggen-Antholz-Vals (DAV) shear zone in the Eastern Alps, are analysed by polarized light and electron microscopy. The microfabrics from both shear zones record a switch from low-temperature plasticity at transient high stress to recrystallization at relaxing stresses at greenschist facies conditions. The development of new grains is dominantly by subgrain rotation and subsequent strain-induced grain-boundary migration in areas of localized high strain developed during initial low-temperature plasticity. The findings suggest that new grains develop at almost random crystallographic orientations at fast rates of stress relaxation (i.e. at low stress), as indicated by recrystallized quartz zones in the Silvretta fault rocks. In contrast, at slow rates of stress relaxation, new grains develop at moderately high stresses with crystallographic preferred orientation characterized by high Schmid factor for basal glide, as indicated by vein quartz samples from the DAV shear zone. Both recorded histories with transient peak stresses and different rates of stress relaxation are interpreted to be related to seismic activity of the fault systems. This study demonstrates that characteristic microfabrics provide important information about the deformation history of natural shear zones developed in different tectonic regimes.
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斜长石择优取向，Foreshore Group 变质沉积物，布拉夫，新西兰
影响因子：
2.9
作者：
D. Shelley
通讯作者：
D. Shelley
Silvrettadecke/Ostalpen 变质岩：温压测量和地球化学 Untersuchungen zur präalpidischen Entwicklung
影响因子：
3.1
作者：
Ralf Schweinehage
通讯作者：
Ralf Schweinehage
阿尔卑斯山中部的脱离、剪切和压缩
DOI：
10.1130/mem158-p191
发表时间：
1983
期刊：
Geological Society of America Memoirs
影响因子：
--
作者：
H. Laubscher
通讯作者：
H. Laubscher
DOI：
10.4028/www.scientific.net/msf.467-470.107
发表时间：
2004
期刊：
Materials Science Forum
影响因子：
--
作者：
J. Humphreys
通讯作者：
J. Humphreys
DOI：
--
发表时间：
1977
期刊：
影响因子：
--
作者：
S. White
通讯作者：
S. White