nigel.stanger / Digital_Repository
Transfer to URL with SHA Find file
Newer
Older
Digital_Repository / Misc / Mass downloads / UTas / 693.html
Nigel Stanger on 7 May 2013 26 KB - Imported Misc directory.
Raw Blame History 
  1. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
  2. "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
  3. <html>
  4.   <head>
  5.     <title>UTas ePrints - U-Pb dating of zircon by LA-ICP-MS</title>
  6.     <script type="text/javascript" src="http://eprints.utas.edu.au/javascript/auto.js"><!-- padder --></script>
  7.     <style type="text/css" media="screen">@import url(http://eprints.utas.edu.au/style/auto.css);</style>
  8.     <style type="text/css" media="print">@import url(http://eprints.utas.edu.au/style/print.css);</style>
  9.     <link rel="icon" href="/images/eprints/favicon.ico" type="image/x-icon" />
  10.     <link rel="shortcut icon" href="/images/eprints/favicon.ico" type="image/x-icon" />
  11.     <link rel="Top" href="http://eprints.utas.edu.au/" />
  12.     <link rel="Search" href="http://eprints.utas.edu.au/cgi/search" />
  13.     <meta content="Chang, Z." name="eprints.creators_name" />
  14. <meta content="Vervoort, J. D." name="eprints.creators_name" />
  15. <meta content="McClelland, W. C." name="eprints.creators_name" />
  16. <meta content="Knaack, C." name="eprints.creators_name" />
  17. <meta content="zhaoshan.chang@utas.edu.au" name="eprints.creators_id" />
  18. <meta content="" name="eprints.creators_id" />
  19. <meta content="" name="eprints.creators_id" />
  20. <meta content="" name="eprints.creators_id" />
  21. <meta content="article" name="eprints.type" />
  22. <meta content="2007-02-08" name="eprints.datestamp" />
  23. <meta content="2008-01-31T02:41:41Z" name="eprints.lastmod" />
  24. <meta content="show" name="eprints.metadata_visibility" />
  25. <meta content="U-Pb dating of zircon by LA-ICP-MS" name="eprints.title" />
  26. <meta content="pub" name="eprints.ispublished" />
  27. <meta content="260100" name="eprints.subjects" />
  28. <meta content="restricted" name="eprints.full_text_status" />
  29. <meta content="laser ablation; magnetic sector ICP-MS; U-Pb dating; zircon dating." name="eprints.keywords" />
  30. <meta content="http://www.agu.org/pubs/crossref/2006/2005GC001100.shtml" name="eprints.note" />
  31. <meta content="In this study we used LA-ICP-MS (laser ablation-inductively coupled plasma-mass spectrometry) to
  32. determine U-Pb ages of 5 zircon samples of known age (1800 Ma to 50 Ma) in order to determine the
  33. reproducibility, precision, and accuracy of this geochronologic technique. This work was performed using
  34. a ThermoFinnigan Element2 magnetic sector double-focusing ICP-MS coupled with a New Wave
  35. Research UP-213 laser system. The laser ablation pit sizes ranged from 30 to 40 mm in diameter. Laserinduced
  36. time-dependent fractionation is corrected by normalizing measured ratios in both standards and
  37. samples to the beginning of the analysis using the intercept method. Static fractionation, including those
  38. caused during laser ablation and due to instrumental discrimination, is corrected using external zircon
  39. standards. Total uncertainty for each laser analysis of an unknown is combined quadratically from the
  40. uncertainty in the measured isotope ratios of the unknown and the uncertainty in the fractionation factors
  41. calculated from the measurement of standards. For individual analyses we estimate that the accuracy and
  42. precision are better than 4% at the 2 sigma level, with the largest contribution in uncertainty from the
  43. measurement of the standards. Accuracy of age determinations in this study is on the order of 1% on the
  44. basis of comparing the weighted average of the LA-ICP-MS determinations to the TIMS ages. Due to
  45. unresolved contributions to uncertainty from the lack of a common Pb correction and from potential matrix
  46. effects between standards and unknowns, however, this estimate cannot be universally applied to all
  47. unknowns. Nevertheless, the results of this study provide an example of the type of precision and accuracy
  48. that may be possible with this technique under ideal conditions. In summary, the laser ablation technique,
  49. using a magnetic sector ICP-MS, can be used for the U-Pb dating of zircons with a wide range of ages and
  50. is a useful complement to the established TIMS and SHRIMP techniques. This technique is especially well
  51. suited to reconnaissance geochronologic and detrital zircon studies." name="eprints.abstract" />
  52. <meta content="2006-05-10" name="eprints.date" />
  53. <meta content="published" name="eprints.date_type" />
  54. <meta content="Geochemistry Geophysics Geosystems" name="eprints.publication" />
  55. <meta content="7" name="eprints.volume" />
  56. <meta content="5" name="eprints.number" />
  57. <meta content="10.1029/2005GC001100" name="eprints.id_number" />
  58. <meta content="UNSPECIFIED" name="eprints.thesis_type" />
  59. <meta content="TRUE" name="eprints.refereed" />
  60. <meta content="1525-2027" name="eprints.issn" />
  61. <meta content="http://dx.doi.org/10.1029/2005GC001100" name="eprints.official_url" />
  62. <meta content="Chang, Z. and Vervoort, J. D. and McClelland, W. C. and Knaack, C. (2006) U-Pb dating of zircon by LA-ICP-MS. Geochemistry Geophysics Geosystems, 7 (5). ISSN 1525-2027" name="eprints.citation" />
  63. <meta content="http://eprints.utas.edu.au/693/1/Chang_et_al.%2C_GGG%2C_2006.pdf" name="eprints.document_url" />
  64. <link rel="schema.DC" href="http://purl.org/DC/elements/1.0/" />
  65. <meta content="U-Pb dating of zircon by LA-ICP-MS" name="DC.title" />
  66. <meta content="Chang, Z." name="DC.creator" />
  67. <meta content="Vervoort, J. D." name="DC.creator" />
  68. <meta content="McClelland, W. C." name="DC.creator" />
  69. <meta content="Knaack, C." name="DC.creator" />
  70. <meta content="260100 Geology" name="DC.subject" />
  71. <meta content="In this study we used LA-ICP-MS (laser ablation-inductively coupled plasma-mass spectrometry) to
  72. determine U-Pb ages of 5 zircon samples of known age (1800 Ma to 50 Ma) in order to determine the
  73. reproducibility, precision, and accuracy of this geochronologic technique. This work was performed using
  74. a ThermoFinnigan Element2 magnetic sector double-focusing ICP-MS coupled with a New Wave
  75. Research UP-213 laser system. The laser ablation pit sizes ranged from 30 to 40 mm in diameter. Laserinduced
  76. time-dependent fractionation is corrected by normalizing measured ratios in both standards and
  77. samples to the beginning of the analysis using the intercept method. Static fractionation, including those
  78. caused during laser ablation and due to instrumental discrimination, is corrected using external zircon
  79. standards. Total uncertainty for each laser analysis of an unknown is combined quadratically from the
  80. uncertainty in the measured isotope ratios of the unknown and the uncertainty in the fractionation factors
  81. calculated from the measurement of standards. For individual analyses we estimate that the accuracy and
  82. precision are better than 4% at the 2 sigma level, with the largest contribution in uncertainty from the
  83. measurement of the standards. Accuracy of age determinations in this study is on the order of 1% on the
  84. basis of comparing the weighted average of the LA-ICP-MS determinations to the TIMS ages. Due to
  85. unresolved contributions to uncertainty from the lack of a common Pb correction and from potential matrix
  86. effects between standards and unknowns, however, this estimate cannot be universally applied to all
  87. unknowns. Nevertheless, the results of this study provide an example of the type of precision and accuracy
  88. that may be possible with this technique under ideal conditions. In summary, the laser ablation technique,
  89. using a magnetic sector ICP-MS, can be used for the U-Pb dating of zircons with a wide range of ages and
  90. is a useful complement to the established TIMS and SHRIMP techniques. This technique is especially well
  91. suited to reconnaissance geochronologic and detrital zircon studies." name="DC.description" />
  92. <meta content="2006-05-10" name="DC.date" />
  93. <meta content="Article" name="DC.type" />
  94. <meta content="PeerReviewed" name="DC.type" />
  95. <meta content="application/pdf" name="DC.format" />
  96. <meta content="http://eprints.utas.edu.au/693/1/Chang_et_al.%2C_GGG%2C_2006.pdf" name="DC.identifier" />
  97. <meta content="http://dx.doi.org/10.1029/2005GC001100" name="DC.relation" />
  98. <meta content="Chang, Z. and Vervoort, J. D. and McClelland, W. C. and Knaack, C. (2006) U-Pb dating of zircon by LA-ICP-MS. Geochemistry Geophysics Geosystems, 7 (5). ISSN 1525-2027" name="DC.identifier" />
  99. <meta content="http://eprints.utas.edu.au/693/" name="DC.relation" />
  100. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/BibTeX/epprod-eprint-693.bib" title="BibTeX" type="text/plain" />
  101. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/ContextObject/epprod-eprint-693.xml" title="OpenURL ContextObject" type="text/xml" />
  102. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/ContextObject::Dissertation/epprod-eprint-693.xml" title="OpenURL Dissertation" type="text/xml" />
  103. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/ContextObject::Journal/epprod-eprint-693.xml" title="OpenURL Journal" type="text/xml" />
  104. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/DC/epprod-eprint-693.txt" title="Dublin Core" type="text/plain" />
  105. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/DIDL/epprod-eprint-693.xml" title="DIDL" type="text/xml" />
  106. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/EndNote/epprod-eprint-693.enw" title="EndNote" type="text/plain" />
  107. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/HTML/epprod-eprint-693.html" title="HTML Citation" type="text/html; charset=utf-8" />
  108. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/METS/epprod-eprint-693.xml" title="METS" type="text/xml" />
  109. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/MODS/epprod-eprint-693.xml" title="MODS" type="text/xml" />
  110. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/RIS/epprod-eprint-693.ris" title="Reference Manager" type="text/plain" />
  111. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/Refer/epprod-eprint-693.refer" title="Refer" type="text/plain" />
  112. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/Simple/epprod-eprint-693text" title="Simple Metadata" type="text/plain" />
  113. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/Text/epprod-eprint-693.txt" title="ASCII Citation" type="text/plain; charset=utf-8" />
  114. <link rel="alternate" href="http://eprints.utas.edu.au/cgi/export/693/XML/epprod-eprint-693.xml" title="EP3 XML" type="text/xml" />
  115.  
  116.   </head>
  117.   <body bgcolor="#ffffff" text="#000000" onLoad="loadRoutine(); MM_preloadImages('images/eprints/ePrints_banner_r5_c5_f2.gif','images/eprints/ePrints_banner_r5_c7_f2.gif','images/eprints/ePrints_banner_r5_c8_f2.gif','images/eprints/ePrints_banner_r5_c9_f2.gif','images/eprints/ePrints_banner_r5_c10_f2.gif','images/eprints/ePrints_banner_r5_c11_f2.gif','images/eprints/ePrints_banner_r6_c4_f2.gif')">
  118.     
  119.     <div class="ep_noprint"><noscript><style type="text/css">@import url(http://eprints.utas.edu.au/style/nojs.css);</style></noscript></div>
  120.  
  121.  
  122.  
  123.  
  124. <table width="795" border="0" cellspacing="0" cellpadding="0">
  125.   <tr>
  126.     <td><script language="JavaScript1.2">mmLoadMenus();</script>
  127.       <table border="0" cellpadding="0" cellspacing="0" width="795">
  128.         <!-- fwtable fwsrc="eprints_banner_final2.png" fwbase="ePrints_banner.gif" fwstyle="Dreamweaver" fwdocid = "1249563342" fwnested="0" -->
  129.         <tr>
  130.           <td><img src="/images/eprints/spacer.gif" width="32" height="1" border="0" alt="" /></td>
  131.           <td><img src="/images/eprints/spacer.gif" width="104" height="1" border="0" alt="" /></td>
  132.           <td><img src="/images/eprints/spacer.gif" width="44" height="1" border="0" alt="" /></td>
  133.           <td><img src="/images/eprints/spacer.gif" width="105" height="1" border="0" alt="" /></td>
  134.           <td><img src="/images/eprints/spacer.gif" width="41" height="1" border="0" alt="" /></td>
  135.           <td><img src="/images/eprints/spacer.gif" width="16" height="1" border="0" alt="" /></td>
  136.           <td><img src="/images/eprints/spacer.gif" width="68" height="1" border="0" alt="" /></td>
  137.           <td><img src="/images/eprints/spacer.gif" width="68" height="1" border="0" alt="" /></td>
  138.           <td><img src="/images/eprints/spacer.gif" width="68" height="1" border="0" alt="" /></td>
  139.           <td><img src="/images/eprints/spacer.gif" width="82" height="1" border="0" alt="" /></td>
  140.           <td><img src="/images/eprints/spacer.gif" width="69" height="1" border="0" alt="" /></td>
  141.           <td><img src="/images/eprints/spacer.gif" width="98" height="1" border="0" alt="" /></td>
  142.           <td><img src="/images/eprints/spacer.gif" width="1" height="1" border="0" alt="" /></td>
  143.         </tr>
  144.         <tr>
  145.           <td colspan="12"><img name="ePrints_banner_r1_c1" src="/images/eprints/ePrints_banner_r1_c1.gif" width="795" height="10" border="0" alt="" /></td>
  146.           <td><img src="/images/eprints/spacer.gif" width="1" height="10" border="0" alt="" /></td>
  147.         </tr>
  148.         <tr>
  149.           <td rowspan="6"><img name="ePrints_banner_r2_c1" src="/images/eprints/ePrints_banner_r2_c1.gif" width="32" height="118" border="0" alt="" /></td>
  150.           <td rowspan="5"><a href="http://www.utas.edu.au/"><img name="ePrints_banner_r2_c2" src="/images/eprints/ePrints_banner_r2_c2.gif" width="104" height="103" border="0" alt="" /></a></td>
  151.           <td colspan="10"><img name="ePrints_banner_r2_c3" src="/images/eprints/ePrints_banner_r2_c3.gif" width="659" height="41" border="0" alt="" /></td>
  152.           <td><img src="/images/eprints/spacer.gif" width="1" height="41" border="0" alt="" /></td>
  153.         </tr>
  154.         <tr>
  155.           <td colspan="3"><a href="http://eprints.utas.edu.au/"><img name="ePrints_banner_r3_c3" src="/images/eprints/ePrints_banner_r3_c3.gif" width="190" height="31" border="0" alt="" /></a></td>
  156.           <td rowspan="2" colspan="7"><img name="ePrints_banner_r3_c6" src="/images/eprints/ePrints_banner_r3_c6.gif" width="469" height="37" border="0" alt="" /></td>
  157.           <td><img src="/images/eprints/spacer.gif" width="1" height="31" border="0" alt="" /></td>
  158.         </tr>
  159.         <tr>
  160.           <td colspan="3"><img name="ePrints_banner_r4_c3" src="/images/eprints/ePrints_banner_r4_c3.gif" width="190" height="6" border="0" alt="" /></td>
  161.           <td><img src="/images/eprints/spacer.gif" width="1" height="6" border="0" alt="" /></td>
  162.         </tr>
  163.         <tr>
  164.           <td colspan="2"><img name="ePrints_banner_r5_c3" src="/images/eprints/ePrints_banner_r5_c3.gif" width="149" height="1" border="0" alt="" /></td>
  165.           <td rowspan="2" colspan="2"><a href="/information.html" onMouseOut="MM_swapImgRestore();MM_startTimeout()" onMouseOver="MM_showMenu(window.mm_menu_0821132634_0,0,25,null,'ePrints_banner_r5_c5');MM_swapImage('ePrints_banner_r5_c5','','/images/eprints/ePrints_banner_r5_c5_f2.gif',1);"><img name="ePrints_banner_r5_c5" src="/images/eprints/ePrints_banner_r5_c5.gif" width="57" height="25" border="0" alt="About" /></a></td>
  166.           <td rowspan="2"><a href="/view/" onMouseOut="MM_swapImgRestore();MM_startTimeout()" onMouseOver="MM_showMenu(window.mm_menu_0821133021_1,0,25,null,'ePrints_banner_r5_c7');MM_swapImage('ePrints_banner_r5_c7','','/images/eprints/ePrints_banner_r5_c7_f2.gif',1);"><img name="ePrints_banner_r5_c7" src="/images/eprints/ePrints_banner_r5_c7.gif" width="68" height="25" border="0" alt="Browse" /></a></td>
  167.           <td rowspan="2"><a href="/perl/search/simple" onMouseOut="MM_swapImgRestore();MM_startTimeout()" onMouseOver="MM_showMenu(window.mm_menu_0821133201_2,0,25,null,'ePrints_banner_r5_c8');MM_swapImage('ePrints_banner_r5_c8','','/images/eprints/ePrints_banner_r5_c8_f2.gif',1);"><img name="ePrints_banner_r5_c8" src="/images/eprints/ePrints_banner_r5_c8.gif" width="68" height="25" border="0" alt="Search" /></a></td>
  168.           <td rowspan="2"><a href="/perl/register" onMouseOut="MM_swapImgRestore();MM_startTimeout();" onMouseOver="MM_showMenu(window.mm_menu_1018171924_3,0,25,null,'ePrints_banner_r5_c9');MM_swapImage('ePrints_banner_r5_c9','','/images/eprints/ePrints_banner_r5_c9_f2.gif',1);"><img name="ePrints_banner_r5_c9" src="/images/eprints/ePrints_banner_r5_c9.gif" width="68" height="25" border="0" alt="register" /></a></td>
  169.           <td rowspan="2"><a href="/perl/users/home" onMouseOut="MM_swapImgRestore();MM_startTimeout()" onMouseOver="MM_showMenu(window.mm_menu_0821133422_4,0,25,null,'ePrints_banner_r5_c10');MM_swapImage('ePrints_banner_r5_c10','','/images/eprints/ePrints_banner_r5_c10_f2.gif',1);"><img name="ePrints_banner_r5_c10" src="/images/eprints/ePrints_banner_r5_c10.gif" width="82" height="25" border="0" alt="user area" /></a></td>
  170.           <td rowspan="2"><a href="/help/" onMouseOut="MM_swapImgRestore();MM_startTimeout()" onMouseOver="MM_showMenu(window.mm_menu_0821133514_5,0,25,null,'ePrints_banner_r5_c11');MM_swapImage('ePrints_banner_r5_c11','','/images/eprints/ePrints_banner_r5_c11_f2.gif',1);"><img name="ePrints_banner_r5_c11" src="/images/eprints/ePrints_banner_r5_c11.gif" width="69" height="25" border="0" alt="Help" /></a></td>
  171.           <td rowspan="3" colspan="4"><img name="ePrints_banner_r5_c12" src="/images/eprints/ePrints_banner_r5_c12.gif" width="98" height="40" border="0" alt="" /></td>
  172.           <td><img src="/images/eprints/spacer.gif" width="1" height="1" border="0" alt="" /></td>
  173.         </tr>
  174.         <tr>
  175.           <td rowspan="2"><img name="ePrints_banner_r6_c3" src="/images/eprints/ePrints_banner_r6_c3.gif" width="44" height="39" border="0" alt="ePrints home" /></td>
  176.           <td><a href="/" onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('ePrints_banner_r6_c4','','/images/eprints/ePrints_banner_r6_c4_f2.gif',1);"><img name="ePrints_banner_r6_c4" src="/images/eprints/ePrints_banner_r6_c4.gif" width="105" height="24" border="0" alt="ePrints home" /></a></td>
  177.           <td><img src="/images/eprints/spacer.gif" width="1" height="24" border="0" alt="" /></td>
  178.         </tr>
  179.         <tr>
  180.           <td><img name="ePrints_banner_r7_c2" src="/images/eprints/ePrints_banner_r7_c2.gif" width="104" height="15" border="0" alt="" /></td>
  181.           <td colspan="8"><img name="ePrints_banner_r7_c4" src="/images/eprints/ePrints_banner_r7_c4.gif" width="517" height="15" border="0" alt="" /></td>
  182.           <td><img src="/images/eprints/spacer.gif" width="1" height="15" border="0" alt="" /></td>
  183.         </tr>
  184.       </table></td>
  185.   </tr>
  186.     <tr><td><table width="100%" style="font-size: 90%; border: solid 1px #ccc; padding: 3px"><tr>
  187.       <td align="left"><a href="http://eprints.utas.edu.au/cgi/users/home">Login</a> | <a href="http://eprints.utas.edu.au/cgi/register">Create Account</a></td>
  188.       <td align="right" style="white-space: nowrap">
  189.         <form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/search" style="display:inline">
  190.           <input class="ep_tm_searchbarbox" size="20" type="text" name="q" />
  191.           <input class="ep_tm_searchbarbutton" value="Search" type="submit" name="_action_search" />
  192.           <input type="hidden" name="_order" value="bytitle" />
  193.           <input type="hidden" name="basic_srchtype" value="ALL" />
  194.           <input type="hidden" name="_satisfyall" value="ALL" />
  195.         </form>
  196.       </td>
  197.     </tr></table></td></tr>
  198.   <tr>
  199.     <td class="toplinks"><!-- InstanceBeginEditable name="content" -->
  200.  
  201.  
  202. <div align="center">
  203.   
  204.   <table width="720" class="ep_tm_main"><tr><td align="left">
  205.     <h1 class="ep_tm_pagetitle">U-Pb dating of zircon by LA-ICP-MS</h1>
  206.     <p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">Chang, Z.</span> and <span class="person_name">Vervoort, J. D.</span> and <span class="person_name">McClelland, W. C.</span> and <span class="person_name">Knaack, C.</span> (2006) <xhtml:em>U-Pb dating of zircon by LA-ICP-MS.</xhtml:em> Geochemistry Geophysics Geosystems, 7 (5). ISSN 1525-2027</p><p style="margin-bottom: 1em" class="not_ep_block"></p><table style="margin-bottom: 1em" class="not_ep_block"><tr><td valign="top" style="text-align:center"><a href="http://eprints.utas.edu.au/693/1/Chang_et_al.%2C_GGG%2C_2006.pdf"><img alt="[img]" src="http://eprints.utas.edu.au/style/images/fileicons/application_pdf.png" class="ep_doc_icon" border="0" /></a></td><td valign="top"><a href="http://eprints.utas.edu.au/693/1/Chang_et_al.%2C_GGG%2C_2006.pdf"><span class="ep_document_citation">PDF</span></a> - Full text restricted - Requires a PDF viewer<br />701Kb</td><td><form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/request_doc"><input accept-charset="utf-8" value="705" name="docid" type="hidden" /><div class=""><input value="Request a copy" name="_action_null" class="ep_form_action_button" onclick="return EPJS_button_pushed( '_action_null' )" type="submit" /> </div></form></td></tr></table><p style="margin-bottom: 1em" class="not_ep_block">Official URL: <a href="http://dx.doi.org/10.1029/2005GC001100">http://dx.doi.org/10.1029/2005GC001100</a></p><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">In this study we used LA-ICP-MS (laser ablation-inductively coupled plasma-mass spectrometry) to&#13;
  207. determine U-Pb ages of 5 zircon samples of known age (1800 Ma to 50 Ma) in order to determine the&#13;
  208. reproducibility, precision, and accuracy of this geochronologic technique. This work was performed using&#13;
  209. a ThermoFinnigan Element2 magnetic sector double-focusing ICP-MS coupled with a New Wave&#13;
  210. Research UP-213 laser system. The laser ablation pit sizes ranged from 30 to 40 mm in diameter. Laserinduced&#13;
  211. time-dependent fractionation is corrected by normalizing measured ratios in both standards and&#13;
  212. samples to the beginning of the analysis using the intercept method. Static fractionation, including those&#13;
  213. caused during laser ablation and due to instrumental discrimination, is corrected using external zircon&#13;
  214. standards. Total uncertainty for each laser analysis of an unknown is combined quadratically from the&#13;
  215. uncertainty in the measured isotope ratios of the unknown and the uncertainty in the fractionation factors&#13;
  216. calculated from the measurement of standards. For individual analyses we estimate that the accuracy and&#13;
  217. precision are better than 4% at the 2 sigma level, with the largest contribution in uncertainty from the&#13;
  218. measurement of the standards. Accuracy of age determinations in this study is on the order of 1% on the&#13;
  219. basis of comparing the weighted average of the LA-ICP-MS determinations to the TIMS ages. Due to&#13;
  220. unresolved contributions to uncertainty from the lack of a common Pb correction and from potential matrix&#13;
  221. effects between standards and unknowns, however, this estimate cannot be universally applied to all&#13;
  222. unknowns. Nevertheless, the results of this study provide an example of the type of precision and accuracy&#13;
  223. that may be possible with this technique under ideal conditions. In summary, the laser ablation technique,&#13;
  224. using a magnetic sector ICP-MS, can be used for the U-Pb dating of zircons with a wide range of ages and&#13;
  225. is a useful complement to the established TIMS and SHRIMP techniques. This technique is especially well&#13;
  226. suited to reconnaissance geochronologic and detrital zircon studies.</p></div><table style="margin-bottom: 1em" cellpadding="3" class="not_ep_block" border="0"><tr><th valign="top" class="ep_row">Item Type:</th><td valign="top" class="ep_row">Article</td></tr><tr><th valign="top" class="ep_row">Additional Information:</th><td valign="top" class="ep_row">http://www.agu.org/pubs/crossref/2006/2005GC001100.shtml</td></tr><tr><th valign="top" class="ep_row">Keywords:</th><td valign="top" class="ep_row">laser ablation; magnetic sector ICP-MS; U-Pb dating; zircon dating.</td></tr><tr><th valign="top" class="ep_row">Subjects:</th><td valign="top" class="ep_row"><a href="http://eprints.utas.edu.au/view/subjects/260100.html">260000 Earth Sciences &gt; 260100 Geology</a></td></tr><tr><th valign="top" class="ep_row">Collections:</th><td valign="top" class="ep_row">UNSPECIFIED</td></tr><tr><th valign="top" class="ep_row">ID Code:</th><td valign="top" class="ep_row">693</td></tr><tr><th valign="top" class="ep_row">Deposited By:</th><td valign="top" class="ep_row"><span class="ep_name_citation"><span class="person_name">Mr Ruben Chan</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">08 Feb 2007</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">31 Jan 2008 13:41</td></tr><tr><th valign="top" class="ep_row">ePrint Statistics:</th><td valign="top" class="ep_row"><a target="ePrintStats" href="/es/index.php?action=show_detail_eprint;id=693;">View statistics for this ePrint</a></td></tr></table><p align="right">Repository Staff Only: <a href="http://eprints.utas.edu.au/cgi/users/home?screen=EPrint::View&amp;eprintid=693">item control page</a></p>
  227.   </td></tr></table>
  228. </div>
  229.  
  230.  
  231.  
  232.     <!-- InstanceEndEditable --></td>
  233.   </tr>
  234.   <tr>
  235.     <td><!-- #BeginLibraryItem "/Library/footer_eprints.lbi" -->
  236.     <table width="795" border="0" align="left" cellpadding="0" class="footer">
  237.   <tr valign="top">
  238. <td colspan="2"><div align="center"><a href="http://www.utas.edu.au">UTAS home</a> | <a href="http://www.utas.edu.au/library/">Library home</a> | <a href="/">ePrints home</a> | <a href="/contact.html">contact</a> | <a href="/information.html">about</a> | <a href="/view/">browse</a> | <a href="/perl/search/simple">search</a> | <a href="/perl/register">register</a> | <a href="/perl/users/home">user area</a> | <a href="/help/">help</a></div><br /></td>
  239. </tr>
  240. <tr><td colspan="2"><p><img src="/images/eprints/footerline.gif" width="100%" height="4" /></p></td></tr>
  241.       <tr valign="top">
  242.         <td width="68%" class="footer">Authorised by the University Librarian<br />
  243. © University of Tasmania ABN 30 764 374 782<br />
  244.       <a href="http://www.utas.edu.au/cricos/">CRICOS Provider Code 00586B</a> | <a href="http://www.utas.edu.au/copyright/copyright_disclaimers.html">Copyright &amp; Disclaimers</a> | <a href="http://www.utas.edu.au/accessibility/index.html">Accessibility</a> | <a href="http://eprints.utas.edu.au/feedback/">Site Feedback</a>  </td>
  245.         <td width="32%"><div align="right">
  246.             <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><img src="http://www.utas.edu.au/shared/logos/unioftasstrip.gif" alt="University of Tasmania Home Page" width="260" height="16" border="0" align="right" /></a></p>
  247.             <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><br />
  248.             </a></p>
  249.         </div></td>
  250.       </tr>
  251.       <tr valign="top">
  252.         <td><p>  </p></td>
  253.         <td><div align="right"><span class="NoPrint"><a href="http://www.eprints.org/software/"><img src="/images/eprintslogo.gif" alt="ePrints logo" width="77" height="29" border="0" align="bottom" /></a></span></div></td>
  254.       </tr>
  255.     </table>
  256.     <!-- #EndLibraryItem -->
  257.     <div align="center"></div></td>
  258.   </tr>
  259. </table>
  260.  
  261.   </body>
  262. </html>