Strain localization in vesicular magma: Implications for rheology and fragmentation

Abstract

Research Article| November 01, 2009 Strain localization in vesicular magma: Implications for rheology and fragmentation Heather M.N. Wright; Heather M.N. Wright 1School of Geosciences, Building 28, Monash University, Clayton, VIC 3800, Australia Search for other works by this author on: GSW Google Scholar Roberto F. Weinberg Roberto F. Weinberg 1School of Geosciences, Building 28, Monash University, Clayton, VIC 3800, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information Heather M.N. Wright 1School of Geosciences, Building 28, Monash University, Clayton, VIC 3800, Australia Roberto F. Weinberg 1School of Geosciences, Building 28, Monash University, Clayton, VIC 3800, Australia Publisher: Geological Society of America Received: 05 Mar 2009 Revision Received: 16 Jun 2009 Accepted: 22 Jun 2009 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2009 Geological Society of America Geology (2009) 37 (11): 1023–1026. https://doi.org/10.1130/G30199A.1 Article history Received: 05 Mar 2009 Revision Received: 16 Jun 2009 Accepted: 22 Jun 2009 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation Heather M.N. Wright, Roberto F. Weinberg; Strain localization in vesicular magma: Implications for rheology and fragmentation. Geology 2009;; 37 (11): 1023–1026. doi: https://doi.org/10.1130/G30199A.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The rheology of two- or three-phase magmas has been the focus of much interest because it controls magma ascent and eruption behavior. Research on magma rheology has typically considered homogeneous flow. Here we demonstrate, based on natural examples, that strain resulting from viscous flow preceding explosive fragmentation localizes into shear zones at a microscopic scale. Strain localization affects the rheological behavior of magmas, modifying predictions based on experiments. Localization leads to high-strain-rate shear zones, where elongated, sheared vesicles and shear heating have a weakening effect, surrounding regions of relatively low strain rate, where subequant vesicles have a strengthening effect. Thus, energy is dissipated more efficiently into localized bands, where strain rate increases through feedback effects and can lead to melt fragmentation. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.