Chen Xiao, Godel Belinda, Verrall Michael
CSIRO Mineral Resources, Australian Resources Research Centre, 26 Dick Perry Avenue, Kensington, WA 6151, Australia.
Microsc Microanal. 2023 Dec 21;29(6):1901-1920. doi: 10.1093/micmic/ozad130.
Understanding how minerals are spatially distributed within natural materials and their textures is indispensable to understanding the fundamental processes of how these materials form and how they will behave from a mining engineering perspective. In the past few years, laboratory diffraction contrast tomography (LabDCT) has emerged as a nondestructive technique for 3D mapping of crystallographic orientations in polycrystalline samples. In this study, we demonstrate the application of LabDCT on both chromite sand and a complex chromitite sample from the Merensky Reef (Bushveld Complex, South Africa). Both samples were scanned using LabDCT and Electron Backscatter Diffraction (EBSD), and the obtained results were rigorously evaluated using a comprehensive set of qualitative and quantitative characterization techniques. The quality of LabDCT results was accessed by using the "completeness" value, while the inaccuracies were thoroughly discussed, along with proposed potential solutions. The results indicate that the grain orientations obtained from LabDCT are comparable to that of 2D EBSD but have the advantage of collecting true 3D size, shape, and textural information. This study highlights the significant contribution of LabDCT in the understanding of complex rock materials from an earth science perspective, particularly in characterizing mineral texture and crystallography in 3D.
了解矿物在天然材料及其结构中的空间分布，对于从采矿工程角度理解这些材料的形成过程及其行为方式的基本过程至关重要。在过去几年中，实验室衍射对比断层扫描（LabDCT）已成为一种用于多晶样品晶体取向三维映射的无损技术。在本研究中，我们展示了LabDCT在铬铁矿砂和来自梅伦斯基礁（南非布什维尔德杂岩体）的复杂铬铁岩样品上的应用。使用LabDCT和电子背散射衍射（EBSD）对两个样品进行了扫描，并使用一套全面的定性和定量表征技术对所得结果进行了严格评估。通过使用“完整性”值来评估LabDCT结果的质量，同时对不准确之处进行了深入讨论，并提出了潜在的解决方案。结果表明，从LabDCT获得的晶粒取向与二维EBSD的结果相当，但具有收集真实三维尺寸、形状和结构信息的优势。本研究突出了LabDCT在从地球科学角度理解复杂岩石材料方面的重要贡献，特别是在三维表征矿物结构和晶体学方面。
