World Library  
Flag as Inappropriate
Email this Article

Volcanic glass

Article Id: WHEBN0000247326
Reproduction Date:

Title: Volcanic glass  
Author: World Heritage Encyclopedia
Language: English
Subject: Volcanic ash, Types of volcanic eruptions, Devastation Trail, Basalt, Glass
Collection: Glass in Nature, Volcanic Rocks, Volcanology
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Volcanic glass

A sand grain of volcanic glass under the petrographic microscope. Its amorphous nature makes it go extinct in cross-polarized light (bottom frame). Scale box in millimeters.

Volcanic glass is the amorphous (uncrystallized) product of rapidly cooling magma. Like all types of glass, it is a state of matter intermediate between the close-packed, highly ordered array of a crystal and the highly disordered array of gas.[1] Volcanic glass can refer to the interstitial, or matrix material in an aphanitic (fine grained) volcanic rock or can refer to any of several types of vitreous igneous rocks. Most commonly, it refers to obsidian, a rhyolitic glass with high silica content.

Other types of volcanic glass include:

  • Pumice, which is considered a glass because it has no crystal structure.
  • Apache tears, a kind of nodular obsidian.
  • Tachylite (also spelled tachylyte), a basaltic glass with relatively low silica content.
  • Sideromelane, a less common form tachylyte.
  • Palagonite, a basaltic glass with relatively low silica content.
  • Hyaloclastite, a hydrated tuff-like breccia of sideromelane and palagonite.
  • Pele's hair, threads or fibers of volcanic glass, usually basaltic.
  • Pele's tears, tear-like drops of volcanic glass, usually basaltic.
  • Limu o Pele (Pele's seaweed), thin sheets and flakes of brownish-green to near-clear volcanic glass, usually basaltic.

References

  1. ^ Bates and Jackson, 1984, Dictionary of Geological Terms, 3rd ed., Prepared by the American Geological Institute
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 



Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.