<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>S.H. Gunn</dc:contributor>
  <dc:contributor>M. A. Lanphere</dc:contributor>
  <dc:contributor>J. L. Wooden</dc:contributor>
  <dc:creator>C. R. Bacon</dc:creator>
  <dc:date>1994</dc:date>
  <dc:description>&lt;p&gt;Quaternary lavas and pyroclastic rocks of Mount Mazama, Crater lake caldera, and the surrounding area have variable Sr, Nd, and Pb isotopic compositions. High-alumina olivine tholeiites have 87Ar/86Ar ratios of 0.70346-0.70364; basaltic andesite, 0.70349-0.70372; shoshonitic basaltic andesite, 0.70374-0.70388; and andesite, 0.70324-0.70383. Dacites of Mount Mazama have 87Sr/ 86Sr ratios of 0.70348-0.70373. Most rhyodacites converge on 0.7037. Andesitic to mafic-cumulate scoriae of the climatic eruption, and enclaves in pre-climactic rhyodacites, cluster in two groups but show nearly the entire 87Sr/86Sr range of the data set, confirming previously suggested introduction of diverse parental magmas into the growing climactic chamber. Magma evolution is described.&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1093/petrology/35.6.1521</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Oxford Academic</dc:publisher>
  <dc:title>Multiple isotopic components in Quaternary volcanic rocks of the Cascade Arc near Crater lake, Oregon</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>