含铀Srilankite的EBSD和SAED研究

含铀Srilankite的EBSD和SAED研究

魏小燕¹，周宁超^1,2*，王立社¹，董  会¹，汪双双¹

（1.中国地质调查局西安地质调查中心，陕西 西安 710054；2.西北大学地质学系，陕西 西安 710069）

摘  要  以往人们发现的Srilankite中铀含量基本在0.2%以下，高铀含量的Srilankite的报道中也只有产状和化学组成方面的研究，而关于铀含量较高的含铀Srilankite结构方面的研究尚不曾报道。本文在前人研究的基础上，鉴于含铀Srilankite的小尺寸，故选用电子背散射衍射（EBSD）和选区电子衍射（SAED）方法对不同铀含量下的样品进行分析与探讨。结果表明，当UO₂含量在1.26%~9.20%时，即低铀-中铀含量时，Srilankite晶体结构并未随着铀原子的进入而发生显著改变；当UO₂含量在20.60%时，即处于高铀阶段时，矿物的晶体结构已发生蜕晶化。

关键词  含铀Srilankite；EBSD；SAED；蜕晶化

中图分类号：P578.94⁺1；TG115.21⁺5.3   文献标识码：A   doi:10.3969/j.issn.1000-6281.2019.03.007

EBSD and SAED study of the uranium-bearing srilankite

WEI Xiao-yan¹，ZHOU Ning-chao^1，2*，WANG Li-she¹，DONG Hui¹，WANG Shuang-shuang¹

(1.Xi’an Center of Geological Survey, ChinaGeology Survey, Xi’an Shannxi 710054；2.Department of Geology, Northwest University, Xi’an Shannxi 710069，China)

Abstract  In the past, the uranium content in discovered srilankite was basically below 0.2%. Only studies on the occurrence and chemical composition of high uranium content srilankite were reported, while studies on the structure of high uranium content uranium-bearing srilankite were not reported.  On the basis of previous studies, in view of the small size of uranium-bearing srilankite, electron backscattering diffraction (EBSD) and selected area electron diffraction (SAED) methods were used to analyze and discuss samples with different uranium contents. The results showed that the crystal structure of srilankitedo did not change significantly with the entry of uranium atoms when the UO₂ content was 1.26%-9.20%, that is, when the uranium content was low –medium uranium content. When the UO₂ content was 20.60%, that is, at the stage of high uraniumcontent, the crystal structure of this mineral has undergone amorphization.

Keywords  uranium-bearing srilankite；EBSD；SAED；amorphization

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[1] WILLGALLIS A，SIEGMANN E，HETTIARATCHI T. Srilankite, a new Zr-Ti-oxide mineral [J]. Neues Jahrb Mineral Monatsh，1983，4：151-157.

[2] WILLGALLIS A, HARTL H. (Zr_0.33Ti_0.67)O₂–Einnatürliches zirkonium-titan oxidmit α-PbO₂-struktur[J]. Zeitschrift für Kristallographie，1983，164：59-66.

[3] DUNN P J，GRICE J D，FLEISCHER M，et al.  New mineral names[J].  American Mineralogist，1984，69：210-215.

[4] WANG L，ESSENE E J，ZHANG Y.  Mineral inclusions in pyrope crystals from Garnet Ridge, Arizona, USA:implications for processes in the upper mantle [J].  Contrib Mineral Petrol，1999，135：164-178.

[5] BINGEN B，AUSTRHEIM H，WHITEHOUSE M.  Ilmenite as a source for zirconium during high-grade metamorphism? Textural evidence from the Caledonides of Western Norway and implications for zircon geochronology[J].  Journal of Petrology，2001，42：355-375.

[6] MORISHITA T，MAEDA J，MIYASHITA S，et al. Magmatic srilankite (Ti₂ZrO₆) in gabbroic vein cutting oceanic peridotites: An unusual product of peridotite-melt interactions beneath slow-spreading ridges [J] . American Mineralogist，2004，89：759-766.

[7] TROITZSCH U, CHRISTY A G, ELLIS D J. The crystal structure of disordered (Zr,Ti)O₂ solid solution including srilankite: evolution towards tetragonal ZrO₂ with increasing Zr[J] .  Physics and Chemistry of Minerals，2005，32：504-514.

[8] KONZETT J，WIRTH R，HAUZENBERGER C，et al.  Two episodes of fluid migration in the Kaapvaal Craton lithospheric mantle associated with Cretaceous kimberlite activity: evidence from aharzburgite containing aunique assemblage of metasomatic zirconium-phases [J].  Lithos，2013，182-183：165-184.

[9] KORINEVSKY V G，BLINOV I A.  First find of srilankite in the Urals [J].  Geochemistry，2016，2：204-207.

[10] GOTTMAN I A, PUSHKAREV E V, KHILLER V V.  Uranium-bearing srilankite from high-pressure garnetitesof the southern Urals: first data [J] . Doklady Earth Sciences，2018，479(2)：529-533.

[11] 刘亚非, 王立社, 魏小燕, 等.  应用电子微探针-扫描电镜-拉曼光谱-电子背散射衍射研究一种未知Ti-Zr-U氧化物的矿物学特征[J] . 岩矿测试，2016，35(1)：48-55.

[12] MA C, ROSSMAN G R. Barioperovskite, BaTiO₃, a new mineral from the Benitoite Mine, California [J] . American Mineralogist，2008，93：154-157.

[13] ISA J, MA C, RUBIN A E. Joegoldsteinite: A new sulfide mineral (MnCr₂S₄) from the Social Circle IVA iron meteorite [J] . American Mineralogist，2016，101：1217-1221.

[14] MA C, BECKETT J R. Majindeite, Mg₂Mo₃O₈, a new mineral from the Allende meteorite and a witness to post-crystallization oxidation of a Ca-Al-rich refractory inclusion [J] .  American Mineralogist，2016，101：1161-1170.

[15] DOBRZHINETSKAYA L F，WIRTH R，YANG J，et al.  Qingsongite, natural cubic boron nitride: the first boron mineral from the Earth’s mantle [J] .  American Mineralogist，2014，99：764-772.

[16] 郭明虎, 林川. 振动抛光在EBSD试样制备中的应用[J] . 电子显微学报，2011，30(4/5)：424-427.

[17] 韩伟，肖思群. 聚焦离子束（FIB）及其应用[J] . 中国材料进展，2013，32(12)：716-727.

[18] 潘兆橹. 结晶学及矿物学[M] . 北京：地质出版社，1984，132.