J.K. Bohlke
Stanley J. Mroczkowski
Janet E. Hannon
2008
<div class="abstract-group"><div class="article-section__content en main"><p><span>BaSO</span><sub>4</sub><span> precipitated from mixed salt solutions by common techniques for SO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/83bf173f-9ddf-45a9-b6c6-202c9306b7b5/tex2gif-stack-1.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-1" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/83bf173f-9ddf-45a9-b6c6-202c9306b7b5/tex2gif-stack-1.gif"><span> isotopic analysis may contain quantities of H</span><sub>2</sub><span>O and NO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/a78b33e9-d28c-4cad-835a-4ada6ce06cc2/tex2gif-stack-2.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-2" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/a78b33e9-d28c-4cad-835a-4ada6ce06cc2/tex2gif-stack-2.gif"><span> that introduce errors in O isotope measurements. Experiments with synthetic solutions indicate that </span><i>δ</i><sup>18</sup><span>O values of CO produced by decomposition of precipitated BaSO</span><sub>4</sub><span> in a carbon reactor may be either too low or too high, depending on the relative concentrations of SO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/66af183c-cb0d-4e3f-81ad-1aaee3b8e298/tex2gif-stack-3.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-3" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/66af183c-cb0d-4e3f-81ad-1aaee3b8e298/tex2gif-stack-3.gif"><span> and NO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/74d752cb-da6c-421d-aa00-af14c6b43bca/tex2gif-stack-4.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-4" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/74d752cb-da6c-421d-aa00-af14c6b43bca/tex2gif-stack-4.gif"><span> and the </span><i>δ</i><sup>18</sup><span>O values of the H</span><sub>2</sub><span>O, NO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/f0275cf0-ed65-4f89-b9bd-e0c0f3c35d90/tex2gif-stack-5.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-5" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/f0275cf0-ed65-4f89-b9bd-e0c0f3c35d90/tex2gif-stack-5.gif"><span>, and SO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/36e44e54-21cc-4125-b9ff-deb91eac0931/tex2gif-stack-6.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-6" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/36e44e54-21cc-4125-b9ff-deb91eac0931/tex2gif-stack-6.gif"><span>. Typical </span><i>δ</i><sup>18</sup><span>O errors are of the order of 0.5 to 1‰ in many sample types, and can be larger in samples containing atmospheric NO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/d18884a5-8da9-41db-bd5e-7437c531f481/tex2gif-stack-7.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-7" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/d18884a5-8da9-41db-bd5e-7437c531f481/tex2gif-stack-7.gif"><span>, which can cause similar errors in </span><i>δ</i><sup>17</sup><span>O and Δ</span><sup>17</sup><span>O. These errors can be reduced by (1) ion chromatographic separation of SO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/bbe88d9b-089d-48e8-b757-ebbd571fb106/tex2gif-stack-8.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-8" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/bbe88d9b-089d-48e8-b757-ebbd571fb106/tex2gif-stack-8.gif"><span> from NO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/c174298f-264f-4ec4-a82e-4f49f26396d5/tex2gif-stack-9.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-9" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/c174298f-264f-4ec4-a82e-4f49f26396d5/tex2gif-stack-9.gif"><span>, (2) increasing the salinity of the solutions before precipitating BaSO</span><sub>4</sub><span> to minimize incorporation of H</span><sub>2</sub><span>O, (3) heating BaSO</span><sub>4</sub><span> under vacuum to remove H</span><sub>2</sub><span>O, (4) preparing isotopic reference materials as aqueous samples to mimic the conditions of the samples, and (5) adjusting measured </span><i>δ</i><sup>18</sup><span>O values based on amounts and isotopic compositions of coexisting H</span><sub>2</sub><span>O and NO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/5ea7c947-64ff-40c9-9f8f-593aebd44dea/tex2gif-stack-10.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-10" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/5ea7c947-64ff-40c9-9f8f-593aebd44dea/tex2gif-stack-10.gif"><span>. These procedures are demonstrated for SO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/eaee3606-dcef-4760-a8e6-62295d92b682/tex2gif-stack-11.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-11" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/eaee3606-dcef-4760-a8e6-62295d92b682/tex2gif-stack-11.gif"><span> isotopic reference materials, synthetic solutions with isotopically known reagents, atmospheric deposition from Shenandoah National Park, Virginia, USA, and sulfate salt deposits from the Atacama Desert, Chile, and Mojave Desert, California, USA. These results have implications for the calibration and use of O isotope data in studies of SO</span><img class="section_image" src="https://wol-prod-cdn.literatumonline.com/cms/attachment/6bd98d1b-3d01-43f6-bf7a-1f81d6799a05/tex2gif-stack-12.gif" alt="urn:x-wiley:09514198:media:RCM3832:tex2gif-stack-12" data-mce-src="https://wol-prod-cdn.literatumonline.com/cms/attachment/6bd98d1b-3d01-43f6-bf7a-1f81d6799a05/tex2gif-stack-12.gif"><span> sources and reaction mechanisms.</span></p></div></div>
application/pdf
10.1002/rcm.3832
en
Wiley
Effects of nitrate and water on the oxygen isotopic analysis of barium sulfate precipitated from water samples
article