Links of Petrology, Geochemistry and Geochronology. Observation of Grain Boundaries in Rocks by High-Resolution Transmission Electron Microscopy.

• HIRAGA Takehiko

  Institute of Mineralogy, Petrology, and Economic Geology, Graduate School of Science, Tohoku University

Bibliographic Information

Other Title

• 岩石学・地球化学・年代学のリンク　　鉱物粒界の直視　　高分解能電子顕微鏡観察
• コウブツ リュウカイ ノ チョクシ コウ ブンカイノウ デンシ ケンビキョウ カンサツ
• 高分解能電子顕微鏡観察

Abstract

Grain boundaries in metamorphic rocks were obsereved by high-resolution transmission electron microscopy. Most of the boundaries have no distinct secondary phases at a nanometer scale. Not only between the same kind of minerals but also between different minerals, mineral grains are directly connected at their boundaries, showing that the structual width of the grain boundaries is less than 0.5nm. Grain boundaries with spheroidal voids are observed in the boundaries. It can be concluded that this type of grain boundary is formed by the healing of microcracks. Low-index plane boundaries are well-developed, showing that this type of boundary has low grain boundary energy. Local structural modification, indicating the segregation of impurities, in grain boundaries is observed. The present results show that the actual width of the grain boundary in rocks is too small for the grain boundary diffusion to be as the dominant transport mechanism.

Journal

• Journal of Geography (Chigaku Zasshi)

  Journal of Geography (Chigaku Zasshi) 108 (2), 110-121, 1999

  Tokyo Geographical Society

Keywords

• rock
• minerals
• grain boundary
• high-resolution electron microscopy

Details

• CRID: 1390282679206536064
• NII Article ID: 10002238876
• NII Book ID: AN00322536
• DOI: 10.5026/jgeography.108.2_110
• ISSN: 18840884
• ISSN: 0022135X
• ISSN: http://id.crossref.org/issn/0022135X
• NDL BIB ID: 4780767
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I4780767
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed