<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title>UTas ePrints - Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration</title> <script type="text/javascript" src="http://eprints.utas.edu.au/javascript/auto.js"><!-- padder --></script> <style type="text/css" media="screen">@import url(http://eprints.utas.edu.au/style/auto.css);</style> <style type="text/css" media="print">@import url(http://eprints.utas.edu.au/style/print.css);</style> <link rel="icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="shortcut icon" href="/images/eprints/favicon.ico" type="image/x-icon" /> <link rel="Top" href="http://eprints.utas.edu.au/" /> <link rel="Search" href="http://eprints.utas.edu.au/cgi/search" /> <meta content="Large, R.R." name="eprints.creators_name" /> <meta content="Bull, S.W." name="eprints.creators_name" /> <meta content="Winefield, P.R." name="eprints.creators_name" /> <meta content="Ross.Large@utas.edu.au" name="eprints.creators_id" /> <meta content="S.Bull@utas.edu.au" name="eprints.creators_id" /> <meta name="eprints.creators_id" /> <meta content="article" name="eprints.type" /> <meta content="2007-09-13" name="eprints.datestamp" /> <meta content="2008-01-29T08:13:29Z" name="eprints.lastmod" /> <meta content="show" name="eprints.metadata_visibility" /> <meta content="Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration" name="eprints.title" /> <meta content="pub" name="eprints.ispublished" /> <meta content="260100" name="eprints.subjects" /> <meta content="restricted" name="eprints.full_text_status" /> <meta content="Sedex, brine pool, C-O isotopes, geochemical halo, dolomite, ankerite, stratiform, massive sulfide" name="eprints.keywords" /> <meta content="A study of carbon and oxygen isotope ratios in fine-grained sedimentary dolomite in the Barney Creek Formation of the McArthur basin demonstrates the presence of an extensive isotope halo surrounding the giant stratiform HYC Zn-Pb-Ag deposit. Dolomite within the halo shows an 18O-enriched and 13C-depleted isotope signature (delta 18O =23 to 26 per mil SMOW, delta 13C= -2 to-3.5 per mil PDB), relative to normal Proterozoic sedimentary dolomite beyond the halo (delta 18O = 20-23 per mil and delta 13C = 0 to -2 per mil). The C-O isotope halo within the dolomitic siltstones extends at least 15 km southwest of the HYC deposit and approximately coincides with a previously defined lithogeochemical halo of elevated Fe, Mn, Zn, Pb, and Tl. Dolomitic siltstone lamellae within the stratiform Zn-Pb-Ag ores at HYC exhibit an isotopic range similar to that of the halo dolomites, suggesting that the ore and halo equilibrated with the same hydrothermal fluid. Modeling of isotopic exchange accompanying fluid-rock interaction suggests that the halo dolomites equilibrated with low-temperature fluids (50 degree-120 degreeC), which were enriched in 18O (delta18O = 5 plus or minus 5 per mil) but with an average crustal carbon isotope signature (delta13C = -6 plus or minus 1 per mil). Our preferred interpretation is that the oxygen and carbon isotope halo at HYC is related to the development of an extensive brine pool. This pool was deepest in the vicinity of the HYC deposit adjacent to the Emu fault, and it became shallower to the southwest away from the fault. Using the carbon isotope fractionation equation between dolomite and HCO3-it is possible to estimate the temperature variation at the base of the brine pool during the accumulation of the Barney Creek Formation. Brine pool temperatures were highest in and adjacent to the HYC deposit (40 degree-70 degreeC) and decreased to values of 17 degree to 30 degree C remote from the deposit. These temperatures are similar to those recorded in the Red Sea brine pool associated with the Atlantis II metalliferous sediment deposit. Based on our work at HYC and Lady Loretta, strata-bound 18O-enriched carbonate lithogeochemical halos may be a characteristic of the Proterozoic stratiform Zn-Pb-Ag deposits of northern Australia. These halos are more extensive than the narrow 18O-depletion halos recorded in dolomites surrounding skarn, Mississippi Valley- type and Irish-style Zn-Pb deposits. This fundamental difference in the isotopic halo characteristics of these groups of zinc deposits is probably related to the low-temperature, synsedimentary brine pool origin of the North Australian SEDEX deposits in contrast to the various replacement and open space fill origins of skarn, Mississippi Valley-type, and Irish-style deposits." name="eprints.abstract" /> <meta content="2001" name="eprints.date" /> <meta content="published" name="eprints.date_type" /> <meta content="Economic Geology" name="eprints.publication" /> <meta content="96" name="eprints.volume" /> <meta content="7" name="eprints.number" /> <meta content="1567-1593" name="eprints.pagerange" /> <meta content="10.2113/96.7.1567" name="eprints.id_number" /> <meta content="UNSPECIFIED" name="eprints.thesis_type" /> <meta content="TRUE" name="eprints.refereed" /> <meta content="0361-0128" name="eprints.issn" /> <meta content="http://dx.doi.org/10.2113/96.7.1567" name="eprints.official_url" /> <meta content="Akande, S.O., and Zentilli, M., 1984, Geologic, fluid inclusion and stable isotope studies of Gays River lead-zinc deposit, Nova Scotia, Canada: ECONOMIC GEOLOGY, v. 79, p. 1187-1211. 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Zheng, Y.F., and Hoefs, J., 1993, Carbon and oxygen isotope covariations in hydrothermal calcites: Mineralium Deposita, v. 28, p. 79-89." name="eprints.referencetext" /> <meta content="Large, R.R. and Bull, S.W. and Winefield, P.R. (2001) Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration. Economic Geology, 96 (7). pp. 1567-1593. ISSN 0361-0128" name="eprints.citation" /> <meta content="http://eprints.utas.edu.au/1830/1/Large%2CBull%2CWinefield_ECON_GEOL_2001.pdf" name="eprints.document_url" /> <link rel="schema.DC" href="http://purl.org/DC/elements/1.0/" /> <meta content="Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration" name="DC.title" /> <meta content="Large, R.R." name="DC.creator" /> <meta content="Bull, S.W." name="DC.creator" /> <meta content="Winefield, P.R." name="DC.creator" /> <meta content="260100 Geology" name="DC.subject" /> <meta content="A study of carbon and oxygen isotope ratios in fine-grained sedimentary dolomite in the Barney Creek Formation of the McArthur basin demonstrates the presence of an extensive isotope halo surrounding the giant stratiform HYC Zn-Pb-Ag deposit. Dolomite within the halo shows an 18O-enriched and 13C-depleted isotope signature (delta 18O =23 to 26 per mil SMOW, delta 13C= -2 to-3.5 per mil PDB), relative to normal Proterozoic sedimentary dolomite beyond the halo (delta 18O = 20-23 per mil and delta 13C = 0 to -2 per mil). The C-O isotope halo within the dolomitic siltstones extends at least 15 km southwest of the HYC deposit and approximately coincides with a previously defined lithogeochemical halo of elevated Fe, Mn, Zn, Pb, and Tl. Dolomitic siltstone lamellae within the stratiform Zn-Pb-Ag ores at HYC exhibit an isotopic range similar to that of the halo dolomites, suggesting that the ore and halo equilibrated with the same hydrothermal fluid. Modeling of isotopic exchange accompanying fluid-rock interaction suggests that the halo dolomites equilibrated with low-temperature fluids (50 degree-120 degreeC), which were enriched in 18O (delta18O = 5 plus or minus 5 per mil) but with an average crustal carbon isotope signature (delta13C = -6 plus or minus 1 per mil). Our preferred interpretation is that the oxygen and carbon isotope halo at HYC is related to the development of an extensive brine pool. This pool was deepest in the vicinity of the HYC deposit adjacent to the Emu fault, and it became shallower to the southwest away from the fault. Using the carbon isotope fractionation equation between dolomite and HCO3-it is possible to estimate the temperature variation at the base of the brine pool during the accumulation of the Barney Creek Formation. Brine pool temperatures were highest in and adjacent to the HYC deposit (40 degree-70 degreeC) and decreased to values of 17 degree to 30 degree C remote from the deposit. These temperatures are similar to those recorded in the Red Sea brine pool associated with the Atlantis II metalliferous sediment deposit. Based on our work at HYC and Lady Loretta, strata-bound 18O-enriched carbonate lithogeochemical halos may be a characteristic of the Proterozoic stratiform Zn-Pb-Ag deposits of northern Australia. These halos are more extensive than the narrow 18O-depletion halos recorded in dolomites surrounding skarn, Mississippi Valley- type and Irish-style Zn-Pb deposits. This fundamental difference in the isotopic halo characteristics of these groups of zinc deposits is probably related to the low-temperature, synsedimentary brine pool origin of the North Australian SEDEX deposits in contrast to the various replacement and open space fill origins of skarn, Mississippi Valley-type, and Irish-style deposits." name="DC.description" /> <meta content="2001" name="DC.date" /> <meta content="Article" name="DC.type" /> <meta content="PeerReviewed" name="DC.type" /> <meta content="application/pdf" name="DC.format" /> <meta content="http://eprints.utas.edu.au/1830/1/Large%2CBull%2CWinefield_ECON_GEOL_2001.pdf" name="DC.identifier" /> <meta content="http://dx.doi.org/10.2113/96.7.1567" name="DC.relation" /> <meta content="Large, R.R. and Bull, S.W. and Winefield, P.R. (2001) Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration. Economic Geology, 96 (7). pp. 1567-1593. 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border: solid 1px #ccc; padding: 3px"><tr> <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> <td align="right" style="white-space: nowrap"> <form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/search" style="display:inline"> <input class="ep_tm_searchbarbox" size="20" type="text" name="q" /> <input class="ep_tm_searchbarbutton" value="Search" type="submit" name="_action_search" /> <input type="hidden" name="_order" value="bytitle" /> <input type="hidden" name="basic_srchtype" value="ALL" /> <input type="hidden" name="_satisfyall" value="ALL" /> </form> </td> </tr></table></td></tr> <tr> <td class="toplinks"><!-- InstanceBeginEditable name="content" --> <div align="center"> <table width="720" class="ep_tm_main"><tr><td align="left"> <h1 class="ep_tm_pagetitle">Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration</h1> <p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">Large, R.R.</span> and <span class="person_name">Bull, S.W.</span> and <span class="person_name">Winefield, P.R.</span> (2001) <xhtml:em>Carbon and Oxygen Isotope Halo in Carbonates Related to the McArthur River (HYC) Zn-Pb-Ag Deposit, North Australia: Implications for Sedimentation, Ore Genesis, and Mineral Exploration.</xhtml:em> Economic Geology, 96 (7). pp. 1567-1593. ISSN 0361-0128</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/1830/1/Large%2CBull%2CWinefield_ECON_GEOL_2001.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/1830/1/Large%2CBull%2CWinefield_ECON_GEOL_2001.pdf"><span class="ep_document_citation">PDF</span></a> - Full text restricted - Requires a PDF viewer<br />444Kb</td><td><form method="get" accept-charset="utf-8" action="http://eprints.utas.edu.au/cgi/request_doc"><input accept-charset="utf-8" value="2302" 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/10.2113/96.7.1567">http://dx.doi.org/10.2113/96.7.1567</a></p><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">A study of carbon and oxygen isotope ratios in fine-grained sedimentary dolomite in the Barney Creek Formation of the McArthur basin demonstrates the presence of an extensive isotope halo surrounding the giant stratiform HYC Zn-Pb-Ag deposit. Dolomite within the halo shows an 18O-enriched and 13C-depleted isotope signature (delta 18O =23 to 26 per mil SMOW, delta 13C= -2 to-3.5 per mil PDB), relative to normal Proterozoic sedimentary dolomite beyond the halo (delta 18O = 20-23 per mil and delta 13C = 0 to -2 per mil). The C-O isotope halo within the dolomitic siltstones extends at least 15 km southwest of the HYC deposit and approximately coincides with a previously defined lithogeochemical halo of elevated Fe, Mn, Zn, Pb, and Tl. Dolomitic siltstone lamellae within the stratiform Zn-Pb-Ag ores at HYC exhibit an isotopic range similar to that of the halo dolomites, suggesting that the ore and halo equilibrated with the same hydrothermal fluid. Modeling of isotopic exchange accompanying fluid-rock interaction suggests that the halo dolomites equilibrated with low-temperature fluids (50 degree-120 degreeC), which were enriched in 18O (delta18O = 5 plus or minus 5 per mil) but with an average crustal carbon isotope signature (delta13C = -6 plus or minus 1 per mil). Our preferred interpretation is that the oxygen and carbon isotope halo at HYC is related to the development of an extensive brine pool. This pool was deepest in the vicinity of the HYC deposit adjacent to the Emu fault, and it became shallower to the southwest away from the fault. Using the carbon isotope fractionation equation between dolomite and HCO3-it is possible to estimate the temperature variation at the base of the brine pool during the accumulation of the Barney Creek Formation. Brine pool temperatures were highest in and adjacent to the HYC deposit (40 degree-70 degreeC) and decreased to values of 17 degree to 30 degree C remote from the deposit. These temperatures are similar to those recorded in the Red Sea brine pool associated with the Atlantis II metalliferous sediment deposit. Based on our work at HYC and Lady Loretta, strata-bound 18O-enriched carbonate lithogeochemical halos may be a characteristic of the Proterozoic stratiform Zn-Pb-Ag deposits of northern Australia. These halos are more extensive than the narrow 18O-depletion halos recorded in dolomites surrounding skarn, Mississippi Valley- type and Irish-style Zn-Pb deposits. This fundamental difference in the isotopic halo characteristics of these groups of zinc deposits is probably related to the low-temperature, synsedimentary brine pool origin of the North Australian SEDEX deposits in contrast to the various replacement and open space fill origins of skarn, Mississippi Valley-type, and Irish-style deposits.</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">Keywords:</th><td valign="top" class="ep_row">Sedex, brine pool, C-O isotopes, geochemical halo, dolomite, ankerite, stratiform, massive sulfide</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 > 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">1830</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">Mrs Katrina Keep</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">13 Sep 2007</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">29 Jan 2008 19:13</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=1830;">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&eprintid=1830">item control page</a></p> </td></tr></table> </div> <!-- InstanceEndEditable --></td> </tr> <tr> <td><!-- #BeginLibraryItem "/Library/footer_eprints.lbi" --> <table width="795" border="0" align="left" cellpadding="0" class="footer"> <tr valign="top"> <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> </tr> <tr><td colspan="2"><p><img src="/images/eprints/footerline.gif" width="100%" height="4" /></p></td></tr> <tr valign="top"> <td width="68%" class="footer">Authorised by the University Librarian<br /> © University of Tasmania ABN 30 764 374 782<br /> <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 & 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> <td width="32%"><div align="right"> <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> <p align="right" class="NoPrint"><a href="http://www.utas.edu.au/"><br /> </a></p> </div></td> </tr> <tr valign="top"> <td><p> </p></td> <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> </tr> </table> <!-- #EndLibraryItem --> <div align="center"></div></td> </tr> </table> </body> </html>