...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Volcanology and Geothermal Research >High-resolution 3D analyses of the shape and internal constituents of small volcanic ash particles: The contribution of SEM micro-computed tomography (SEM micro-CT)
【24h】

High-resolution 3D analyses of the shape and internal constituents of small volcanic ash particles: The contribution of SEM micro-computed tomography (SEM micro-CT)

机译：火山灰小颗粒的形状和内部组成的高分辨率3D分析：SEM微型计算机断层扫描（SEM micro-CT）的贡献

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The morphology of small volcanic ash particles is fundamental to our understanding of magma fragmentation, and in transport modeling of volcanic plumes and clouds. Until recently, the analysis of 3D features in small objects (<250 pm) was either restricted to extrapolations from 2D approaches, partial stereo-imaging, or CT methods having limited spatial resolution and/or accessibility. In this study, an X-ray computed-tomography technique known as SEM micro-CT, also called 3D X-ray ultramicroscopy (3D XuM), was used to investigate the 3D morphology of small volcanic ash particles (125-250 mu m sieve fraction), as well as their vesicle and microcrystal distribution. The samples were selected from four stratigraphically well-established tephra layers of the Meerfelder Maar (West Eifel Volcanic Field, Germany). Resolution tests performed on a Beametr v1 pattern sample along with Monte Carlo simulations of X-ray emission volumes indicated that a spatial resolution of 0.65 pm was obtained for X-ray shadow projections using a standard thermionic SEM and a bulk brass target as X-ray source. Analysis of a smaller volcanic ash particle (64-125 mu m sieve fraction) showed that features with volumes > 20 mu m(3) (similar to 3.5 mu m in diameter) can be successfully reconstructed and quantified. In addition, new functionalities of the Blob3D software were developed to allow the particle shape factors frequently used as input parameters in ash transport and dispersion models to be calculated. This study indicates that SEM micro-CT is very well suited to quantify the various aspects of shape in fine volcanic ash, and potentially also to investigate the 3D morphology and internal structure of any object <0.1 mm(3). (C) 2015 Elsevier B.V. All rights reserved.
机译：火山灰小颗粒的形态对于我们对岩浆破碎的理解以及火山羽和云的迁移模型至关重要。直到最近，对小物体（<250 pm）中3D特征的分析还是局限于2D方法，局部立体成像或空间分辨率和/或可访问性有限的CT方法的外推法。在这项研究中，使用称为SEM micro-CT的X射线计算机断层摄影技术（也称为3D X射线超显微技术（3D XuM））来研究火山灰小颗粒（125-250微米筛）的3D形态。分数），以及它们的囊泡和微晶分布。样品选自Meerfelder Maar（德国西埃菲尔火山场）的四个地层良好的特非拉层。在Beametr v1模式样本上进行的分辨率测试以及X射线发射量的蒙特卡罗模拟表明，使用标准热电子SEM和块状黄铜靶作为X射线，X射线阴影投影的空间分辨率为0.65 pm。资源。对较小的火山灰颗粒（筛分分数为64-125微米）的分析表明，体积大于20微米（3）（直径约3.5微米）的特征可以成功地重建和量化。此外，还开发了Blob3D软件的新功能，可以计算经常用作灰分传输和分散模型输入参数的颗粒形状因子。这项研究表明，SEM micro-CT非常适合量化细火山灰中形状的各个方面，并潜在地还可以研究任何<0.1 mm（3）物体的3D形态和内部结构。 （C）2015 Elsevier B.V.保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号