Electron backscatter diffraction study of twins and intergrowths among quartz crystals in granite
Electron backscatter diffraction study of twins and intergrowths among quartz crystals in granite
复制标题
花岗岩中石英晶体孪生和共生的电子背散射衍射研究
DOI：
10.1107/s0021889813017913
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发表时间：
2013-10
影响因子：
6.1
通讯作者：
Yang Kun-Guang
中科院分区：
文献类型：
--
作者：
Zhao Shan-Rong;Xu Hai-Jun;Wang Qin-Yan;Yang Kun-Guang
石英有各种类型的孪晶律，孪晶石英比非孪晶石英更常见。但由于石英的孪晶律很难用光学或衍射方法测定，因此石英不同孪晶律在岩石中的分布情况至今仍不清楚。本文介绍了用电子背散射衍射（EBSD）测定石英晶体孪晶律的方法。根据这一方法，分析了大别山中段天堂寨岩体花岗岩中石英晶体的相互关系。发现该花岗岩中多菲双晶十分丰富，而其他双晶律（日本、埃斯特雷尔、撒丁岛、布莱索普特和康沃尔语）则十分罕见。除孪晶律外，还发现了多种石英晶体间的共生体，其中的{11\overline 22}、{10\overline 11}、{10\overline 12}、{11\overline 21}和{20\overline 21}面分别是日本孪晶律、埃斯特雷孪晶律、撒丁岛孪晶律、布莱索普孪晶律和康沃尔语孪晶律的简单孪晶面。有趣的是，石英晶体喜欢在这些面的基础上形成共生体，但不喜欢以这些面作为孪晶面形成孪晶。研究表明，花岗岩中石英晶体之间的关系受晶体学取向的控制，导致孪晶和共生体以远远超过随机接触的频率发生。EBSD是确定岩石中石英双晶律和共生体的最佳方法。
Quartz has various types of twin law and twinned quartz is more common than untwinned quartz. However, it is difficult to determine the twin laws of quartz by optical or diffraction methods, so the distribution of the different twin laws of quartz in rocks is still unknown. This paper introduces a method to determine quartz twin laws using electron backscatter diffraction (EBSD). Based on this method, the relationships between quartz crystals in the granite of Tiantangzhai pluton, located at the centre of the Dabie Mountain area, China, are analysed. It is found that the Dauphine twin is very abundant but the other twin laws (Japan, Esterel, Sardinian, Breithaupt and Cornish) are very rare in this granite. Besides twin laws, many kinds of intergrowths among the quartz crystals are also found. In the intergrowths the overlapping faces are {11\overline 22}, {10\overline 11}, {10\overline 12}, {11\overline 21} and {20\overline 21}, which are simply the twin planes of the Japan, Esterel, Sardinian, Breithaupt and Cornish twin laws, respectively. It is interesting that quartz crystals like to form intergrowths based on these faces but do not like to form twins with these faces as a twin plane. This research shows that the relationship between quartz crystals in the granite is controlled by the crystallographic orientation, resulting in the twins and intergrowths occurring at frequencies far exceeding random contact. It is also suggested that EBSD is the best method to determine the twin laws and intergrowths of quartz in a rock.
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影响因子：
5.8
作者：
H. Wenk;I. Lonardelli;S. Vogel;J. Tullis
通讯作者：
H. Wenk;I. Lonardelli;S. Vogel;J. Tullis
影响因子：
3.5
作者：
Menegon, Luca;Piazolo, Sandra;Pennacchioni, Giorgio
通讯作者：
Pennacchioni, Giorgio
影响因子：
6.1
作者：
Y. Page
通讯作者：
Y. Page
影响因子：
3.9
作者：
Haijin Xu;Changqian Ma;K. Ye
通讯作者：
Haijin Xu;Changqian Ma;K. Ye
影响因子：
64.8
作者：
B. A.
通讯作者：
B. A.