<?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>Jennifer S. Fehrenbacher</dc:contributor>
  <dc:contributor>Caitlin E. Reynolds</dc:contributor>
  <dc:contributor>Catherine Z. Davis</dc:contributor>
  <dc:contributor>Howard J. Spero</dc:contributor>
  <dc:creator>Julie N. Richey</dc:creator>
  <dc:date>2022</dc:date>
  <dc:description>&lt;div id="abstracts" class="Abstracts u-font-serif"&gt;&lt;div id="ab005" class="abstract author"&gt;&lt;div id="as005"&gt;&lt;p id="sp0005"&gt;Observations of elevated barium-to-calcium ratios (Ba/Ca) in&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Globorotalia truncatulinoides&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;have been attributed to contaminant phases, deep calcification depth and diagenetic processes. Here we investigate intra- and inter-test Ba/Ca variability in the non-spinose planktic foraminifer,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;G. truncatulinoides&lt;/i&gt;&lt;span&gt;, from a&amp;nbsp;sediment trap&amp;nbsp;time series in the northern&amp;nbsp;Gulf of Mexico&amp;nbsp;to gain insights into the environmental influences on barium enrichment in this and other non-spinose species. We use&amp;nbsp;laser ablation inductively coupled plasma mass spectrometry&amp;nbsp;(LA-ICP-MS) to differentiate between the elemental composition of the crust and lamellar&amp;nbsp;calcite&amp;nbsp;in non-encrusted (&amp;lt;150&amp;nbsp;m calcification depth) and encrusted (&amp;gt;150&amp;nbsp;m calcification depth) specimens of&amp;nbsp;&lt;/span&gt;&lt;i&gt;G. truncatulinoides&lt;/i&gt;. We find that the Ba/Ca ratio in lamellar calcite is between two and three orders of magnitude higher (10–280&amp;nbsp;μmol/mol) than that of the crust (0–3&amp;nbsp;μmol/mol). We include seasonal water column profiles of the Ba/Ca ratio in the northern Gulf of Mexico and determine that the vertical gradient in seawater barium concentration cannot account for the intra-test Ba/Ca variations in&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;G. truncatulinoides&lt;/i&gt;. We find the Ba/Ca ratio of the crust to be within the range observed in co-occurring spinose species of foraminifera (pink and white chromotypes of&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Globigerinoides ruber&lt;/i&gt;, and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Orbulina universa&lt;/i&gt;) while the range of Ba/Ca in lamellar calcite is consistent with co-occurring non-spinose foraminifera (&lt;i&gt;Pulleniatina obliquiloculata&lt;/i&gt;,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Globorotalia menardii&lt;/i&gt;,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;G. tumida&lt;/i&gt;, and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;Neogloboquadrina dutertrei&lt;/i&gt;). Our data are consistent with the hypothesis that&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;G. truncatulinoides&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;calcifies in a marine snow aggregate microenvironment that is enriched in barium relative to ambient seawater. We suggest that&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;G. truncatulinoides&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;crust is formed after the rhizopodia retract and the foraminifer detaches from its marine snow substrate.&lt;/p&gt;&lt;/div&gt;&lt;/div&gt;&lt;/div&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1016/j.gca.2022.07.006</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Elsevier</dc:publisher>
  <dc:title>Barium enrichment in the non-spinose planktic foraminifer, Globorotalia truncatulinoides</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>