Kyanite preserves prograde and retrograde metamorphic events as revealed by cathodoluminescence, geochemistry, and crystallographic orientation
Kyanite preserves prograde and retrograde metamorphic events as revealed by cathodoluminescence, geochemistry, and crystallographic orientation
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阴极发光、地球化学和晶体学取向揭示了蓝晶石保留了顺行和逆行变质事件
DOI：
10.1111/jmg.12593
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发表时间：
2021
影响因子：
3.4
通讯作者：
de Wet, Cameron B.
中科院分区：
文献类型：
--
作者：
Peterman, Emily M.;Jercinovic, Michael J.;Beane, Rachel J.;de Wet, Cameron B.
蓝晶石的阴极发光（CL）图像揭示了几种内部结构，包括扇区分带，振荡分带和不同域之间的交叉关系。在蓝晶石中观察到的许多纹理对应于离散事件，从而将蓝晶石纹理与岩石的压力-温度（P-T）历史联系起来。为了评估蓝晶石保存的变质作用记录，从三个不同的造山带中选择了反映从角闪岩到超高压（UHP）相的P-T条件的变岩。蓝晶石内CL强度、化学和晶体取向变化的交叉相关性表明了以下发现。首先，蓝晶石中原始生长带从多变质岩中保存下来，表明蓝晶石中的生长带在变质事件中持续存在，并且不会被扩散或完全重结晶所消除。在某些样品中，蓝晶石保留了生长过程中反应历史的证据。第二，测量的绝对晶体取向的变化不对应于CL强度的变化，在任何测量的样品，包括蓝晶石双胞胎。第三，扭结带和波动消光都存在于所有样品中，与<010>（100）[001]滑移系中的旋转一致。来自（U）HP样品的蓝晶石比来自低等级岩性的蓝晶石显示出更高的振幅波动，这表明晶体学取向数据可以提供关于沿着P-T路径变形的补充见解。第四，特定的CL和微量元素的蓝晶石签名可以与离散的变质历史，然而，CL强度和颜色的影响，由多种元素，而不是一个单一的控制元素。总之，多代蓝晶石可以通过CL和地球化学数据的仔细交叉相关来识别，当与晶体取向数据相结合时，蓝晶石提供了岩石P-T演化的可靠记录。
Cathodoluminescence (CL) images of kyanite reveal several internal textures, including sector zoning, oscillatory zoning, and cross‐cutting relationships among different domains. Many textures observed in kyanite correspond to discrete events, thereby connecting kyanite textures to the pressure–temperature (P–T) history of the rock. To evaluate the record of metamorphism preserved by kyanite, metapelites were selected from three different orogens that reflectP–Tconditions ranging from amphibolite to ultrahigh‐pressure (UHP) facies. Cross‐correlation of variations in CL intensity, chemistry, and crystal orientation within kyanite indicate the following findings. First, the preservation of original growth zones in kyanite from poly‐metamorphic rocks demonstrates that growth zoning in kyanite persists through metamorphic events and is not erased by diffusion or complete recrystallization. In some samples, kyanite retains evidence of its reaction history during growth. Second, measured changes in absolute crystallographic orientation do not correspond with changes in CL intensity in any of the measured samples, including kyanite twins. Third, both kink banding and undulatory extinction are present across all samples, consistent with rotation about <010> in the (100)[001] slip system. Kyanite from (U)HP samples exhibits higher amplitude undulations than kyanite from lower‐grade lithologies, suggesting that crystallographic orientation data may provide complementary insight about deformation along theP–Tpath. Fourth, specific CL and trace element signatures in kyanite can be correlated with discrete metamorphic histories; yet, CL intensity and colour are affected by multiple elements, not a single controlling element. In sum, multiple generations of kyanite can be identified by careful cross‐correlation of CL and geochemical data, and when combined with crystal orientation data, kyanite provides a robust record of a rock'sP–Tevolution.
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影响因子：
3.1
作者：
J. Konzett
通讯作者：
J. Konzett
影响因子：
3.1
作者：
Whitney, Donna L.;Evans, Bernard W.
通讯作者：
Evans, Bernard W.
萨索斯岛（希腊罗多彼）的变质和交代含蓝晶石矿物组合
影响因子：
2.5
作者：
A. Tarantola;P. Voudouris;Aurélien Eglinger;C. Scheffer;Kimberly Trebus;Marie Bitte;Benjamin Rondeau;C. Mavrogonatos;Ian T. Graham;Marius Etienne;C. Peiffert
通讯作者：
C. Peiffert
蓝晶石、硅线石、红柱石的稳定性关系与变质岩的形成条件
DOI：
--
发表时间：
1950
期刊：
影响因子：
--
作者：
秋穗 都城
通讯作者：
秋穗 都城
变质岩变质和变形过程中形成的主矿物和副矿物的 U-Pb 定年
DOI：
--
发表时间：
1995
期刊：
影响因子：
--
作者：
A. Lanzirotti;G. Hanson
通讯作者：
G. Hanson