<?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>John Wolff</dc:contributor>
  <dc:contributor>Bill Bonnichsen</dc:contributor>
  <dc:contributor>Martha Godchaux</dc:contributor>
  <dc:contributor>Peter Larson</dc:contributor>
  <dc:creator>Scott Boroughs</dc:creator>
  <dc:date>2005</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;The Miocene Bruneau-Jarbidge and adjacent volcanic fields of the central Snake River Plain, southwest Idaho, are dominated by high-temperature rhyolitic tuffs and lavas having an aggregate volume estimated as 7000 km&lt;/span&gt;&lt;span&gt;3&lt;/span&gt;&lt;span&gt;. Samples from units representing at least 50% of this volume are strongly depleted in&amp;nbsp;&lt;/span&gt;&lt;span&gt;18&lt;/span&gt;&lt;span&gt;O, with magmatic feldspar &amp;delta;&lt;/span&gt;&lt;span&gt;18&lt;/span&gt;&lt;span&gt;O&lt;/span&gt;&lt;sub&gt;VSMOW&lt;/sub&gt;&lt;span&gt;&amp;nbsp;(Vienna standard mean ocean water) values between &amp;minus;1.4&amp;permil; and 3.8&amp;permil;. The magnitude of the&amp;nbsp;&lt;/span&gt;&lt;span&gt;18&lt;/span&gt;&lt;span&gt;O depletion and the complete lack of any rhyolites with normal values (7&amp;permil;&amp;ndash;10&amp;permil;) combine to suggest that assimilation or melting of a caldera block altered by near- contemporaneous hydrothermal activity is unlikely. Instead, we envisage generation of the high-temperature rhyolites by shallow melting of Idaho Batholith rocks, under the influence of the Yellowstone hotspot, affected by Eocene meteoric-hydrothermal events. The seeming worldwide scarcity of strongly&amp;nbsp;&lt;/span&gt;&lt;span&gt;18&lt;/span&gt;&lt;span&gt;O-depleted rhyolites may simply reflect a similar scarcity of suitable crustal protoliths.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1130/G21723.1</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Geological Society of America</dc:publisher>
  <dc:title>Large-volume, low-δ&lt;sup&gt;18&lt;/sup&gt;O rhyolites of the central Snake River Plain, Idaho, USA</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>