Name: preparation of authigenic pyrite from methane-bearing sediments for in situ sulfur isotope analysis using sims
Uploaded: 2017-08-31T12:30:00
Description: Watch this Scientific Journal Video about Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS at JoVE.com

This research was jointly funded and supported by the Natural Science Foundation of China (No. 91128101, 41273054, and 41373007), the China Geological Survey Project for South China Sea Gas Hydrate Resource Exploration (No. DD20160211), Fundamental Research Funds for the Central Universities (No. 16lgjc11), and Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (No. 2011). Zhiyong Lin acknowledges the financial support provided by the China Scholarship Council (No. 201506380046). Yang Lu thanks the Guangzhou Elite Project (No. JY201223) and the China Postdoctoral Science Foundation (No. 2016M592565). We are grateful to Dr. Shengxiong Yang, Guangxue Zhang, and Dr. Jinqiang Liang of the Guangzhou Marine Geological Survey for providing samples and valuable suggestions. We thank Dr. Xianhua Li and Dr. Lei Chen of the Institute of Geology and Geophysics (Beijing), Chinese Academy of Sciences, for help with the SIMS analysis. Dr. Xiaoping Xia is thanked for making available the SIMS Lab of the Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, for the filming of this article. The manuscript benefited from comments from Dr. Alisha Dsouza, review editor of JoVE, and two anonymous referees.

1. Collection of Samples from a Sediment Core
Note: The core HS148 was obtained from a site near the gas hydrate drilling zone in the Shenhu area, South China Sea, during a cruise of the R/V Haiyang Sihao in 2006.
<ol>
	<li>Cut the piston core (here, HS148) into sections at intervals of 0.7 m from the top to the bottom (onboard the vessel) and transfer the sections to a cold room (4 &#176;C) for storage after retrieval.</li>
	<li>Transfer the core sections to a cold room (4 &#176;C) in the l...

<ol>
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Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+sulfate-driven+anaerobic+oxidation+of+methane+affects+the+sulfur+isotopic+composition+of+pyrite:+A+SIMS+study+from+the+South+China+Sea.">How sulfate-driven anaerobic oxidation of methane affects the sulfur isotopic composition of pyrite: A SIMS study from the South China Sea.</a> Chem Geol. 440, 26-41 (2016).</li><li>J&#248;rgensen, B. B., B&#246;ttcher, M. E., L&#252;schen, H., Neretin, L. N., Volkov, I. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anaerobic+methane+oxidation+and+a+deep+H2S+sink+generate+isotopically+heavy+sulfides+in+Black+Sea+sediments.">Anaerobic methane oxidation and a deep H2S sink generate isotopically heavy sulfides in Black Sea sediments.</a> Geochim Cosmochim Ac. 68 (9), 2095-2118 (2004).</li><li>Borowski, W. S., Rodriguez, N. M., Paull, C. K., Ussler, III, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Are+34S-enriched+authigenic+sulfide+minerals+a+proxy+for+elevated+methane+flux+and+gas+hydrates+in+the+geologic+record?.">Are 34S-enriched authigenic sulfide minerals a proxy for elevated methane flux and gas hydrates in the geologic record?.</a> Mar Petrol Geol. 43, 381-395 (2013).</li><li>Canfield, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isotope+fractionation+by+natural+populations+of+sulfate-reducing+bacteria.">Isotope fractionation by natural populations of sulfate-reducing bacteria.</a> Geochim Cosmochim Ac. 65 (7), 1117-1124 (2001).</li><li>McKibben, M. A., Eldridge, C. 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W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+sulfur+isotope+analysis+of+sulfide+minerals+by+SIMS:+precision+and+accuracy,+with+application+to+thermometry+of+3.5+Ga+Pilbara+cherts.">In situ sulfur isotope analysis of sulfide minerals by SIMS: precision and accuracy, with application to thermometry of 3.5 Ga Pilbara cherts.</a> Chem Geol. 275 (3-4), 243-253 (2010).</li><li>Farquhar, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathways+for+Neoarchean+pyrite+formation+constrained+by+mass-independent+sulfur+isotopes.">Pathways for Neoarchean pyrite formation constrained by mass-independent sulfur isotopes.</a> Proc Natl Acad Sci USA. 110 (44), 17638-17643 (2013).</li><li>Whitehouse, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiple+sulfur+isotope+determination+by+SIMS:+evaluation+of+reference+sulfides+for+&#916;33S+with+observations+and+a+case+study+on+the+determination+of+&#916;36S.">Multiple sulfur isotope determination by SIMS: evaluation of reference sulfides for &#916;33S with observations and a case study on the determination of &#916;36S.</a> Geostand Geoanal Res. 37 (1), 19-33 (2013).</li><li>Chen, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extreme+variation+of+sulfur+isotopic+compositions+in+pyrite+from+the+Qiuling+sediment-hosted+gold+deposit,+West+Qinling+orogen,+central+China:+an+in+situ+SIMS+study+with+implications+for+the+source+of+sulfur.">Extreme variation of sulfur isotopic compositions in pyrite from the Qiuling sediment-hosted gold deposit, West Qinling orogen, central China: an in situ SIMS study with implications for the source of sulfur.</a> Miner Depos. 50 (6), 643-656 (2015).</li><li>LaFlamme, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+multiple+sulfur+isotope+analysis+by+SIMS+of+pyrite,+chalcopyrite,+pyrrhotite,+and+pentlandite+to+refine+magmatic+ore+genetic+models.">In situ multiple sulfur isotope analysis by SIMS of pyrite, chalcopyrite, pyrrhotite, and pentlandite to refine magmatic ore genetic models.</a> Chem Geol. 444, 1-15 (2016).</li><li>Peckmann, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methane-derived+carbonates+and+authigenic+pyrite+from+the+northwestern+Black+Sea.">Methane-derived carbonates and authigenic pyrite from the northwestern Black Sea.</a> Mar Geol. 177 (1-2), 129-150 (2001).</li><li>Zhang, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphology+and+formation+mechanism+of+pyrite+induced+by+the+anaerobic+oxidation+of+methane+from+the+continental+slope+of+the+NE+South+China+Sea.">Morphology and formation mechanism of pyrite induced by the anaerobic oxidation of methane from the continental slope of the NE South China Sea.</a> J Asian Earth Sci. 92, 293-301 (2014).</li><li>Lin, Z. 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The sulfur isotope analysis of pyrite is a useful approach and can help in identifying the biogeochemical processes that impact pyritization. However, if bulk sulfur isotope analysis is applied, the obtained sulfur isotope signatures commonly represent mixed signals, as sedimentary pyrite aggregates typically consist of multiple, closely interfingering generations. Here, we present a method (i.e., SIMS analysis) for analyzing the in situ sulfur isotopic compositions of various pyrite generations on the ...

Methane emissions from sediments are common along continental margins1,2. However, most of the methane in areas of diffusive seepage is oxidized at the expense of sulfate within the sediments, a process known as SO4-AOM (Equation 1)3,4. The production of sulfide during this process commonly results in the precipitation of pyrite. Also, OSR also drives the formation of pyrite by releasing sulfide (Equation 2)5.
CH4 + SO42&#8211; &#8594; HS&#8211; + HCO3&#8211; + H2O (1)
2CH2O + SO42&#8211; &#8594; H2S + 2HCO3&#8211; (2)
It has been found that authigenic sulfide in the sulfate-methane transition zone (SMTZ) reveals high &#948;34S values, which was suggested to be caused by enhanced SO4-AOM in areas of seepage6,7,8. In contrast, pyrite induced by OSR commonly displays lower &#948;34S values9. However, it is challenging to identify different pyrite generations induced by these processes (i.e., OSR and SO4-AOM) if only a bulk sulfur isotope measurement is used, since the successively formed interfingering pyrite generations are characterized by different isotopic compositions. Therefore, microscale in situ sulfur isotope analysis is required to improve our understanding of the actual mineralizing processes10,11,12. As a versatile technique for in situ isotope analysis, SIMS requires only a few nanograms of sample, which sparked its designation as a nondestructive technique. A primary ion beam sputters the target, causing the emission of secondary ions that are subsequently transported to a mass spectrometer for measuring13. In an early in situ sulfur isotope analysis application of SIMS, Pimminger et al. successfully analyzed the &#948;34S values in galena by using a 10 - 30 &#181;m-diameter beam14. This approach has been increasingly applied to the microanalysis of sulfur isotopic compositions in sulfides, with significant improvements in both measurement precision and resolution11,12,13,14,15,16,17,18,19,20. Pyrite with various morphologic attributes and distinct sulfur stable isotope patterns has been reported from seep and non-seep environments21,22,23,24. However, to the best of our knowledge, prior to our recent SIMS study6, only one study used the in situ sulfur isotope analysis of pyrite from seep environments and revealed large sulfur isotope variability in biogenic pyrite25.
In this study, we applied SIMS to analyze the &#948;34S values of different generations of authigenic pyrite from a seepage site in the South China Sea, which allowed for microscale discrimination of OSR- and SO4-AOM-derived pyrite.

<table border="0" cellpadding="0" cellspacing="0" width="835">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:363px;">secondary ion mass spectroscopy</td>
			<td style="width:128px;">Cameca</td>
			<td style="width:179px;">&#160;IMS-1280</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;thermal field emission scanning electron microscopy</td>
			<td>Quanta</td>
			<td>Quanta 400F</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">elemental analyser - isotope ratio mass spectrometry</td>
			<td>ThermoFinnigan</td>
			<td colspan="2">ThermoFinnigan Delta Plus</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">binocular microscope</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">reflected light microscope</td>
			<td>Carl Zeiss</td>
			<td>3519001617</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">polishing machicine</td>
			<td>Struers</td>
			<td>60210535</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">cutting machicine</td>
			<td>Struers</td>
			<td>50110202</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">carbon/gold coating machicine</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ethanol</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">acetic acid&#160;</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">zinc acetate solution (3%)&#160;&#160;&#160;</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HCl solution (25%)</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">1 M CrCl2 solution</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">0.1 M AgNO3 solution</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">V2O5 powder</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">pure nitrogen</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">syringe</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">filter(&#60;0.45 &#181;m)</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">tin cups</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">round bottom flasks</td>
			<td>any</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">epoxy</td>
			<td>Struers</td>
			<td>41000004</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of authigenic pyrite from methane-bearing sediments for in situ sulfur isotope analysis using sims

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and organiclastic sulfate reduction (OSR) in marine sediments. However, unravelling the complex pyritization sequence is a challenge because of the coexistence of different sequentially formed pyrite phases. This manuscript describes a sample preparation procedure that enables the use of secondary ion mass spectroscopy (SIMS) to obtain in situ &#948;34S values of various pyrite generations. This allows researchers to constrain how SO4-AOM affects pyritization in methane-bearing sediments. SIMS analysis revealed an extreme range in &#948;34S values, spanning from -41.6 to +114.8&#8240;, which is much wider than the range of &#948;34S values obtained by the traditional bulk sulfur isotope analysis of the same samples. Pyrite in the shallow sediment mainly consists of 34S-depleted framboids, suggesting early diagenetic formation by OSR. Deeper in the sediment, more pyrite occurs as overgrowths and euhedral crystals, which display much higher SIMS &#948;34S values than the framboids. Such 34S-enriched pyrite is related to enhanced SO4-AOM at the sulfate-methane transition zone, postdating OSR. High-resolution in situ SIMS sulfur isotope analyses allow for the reconstruction of the pyritization processes, which cannot be resolved by bulk sulfur isotope analysis.

Data Expression - Bulk Sulfur Isotopes:
The bulk sulfur isotope ratio is expressed in relation to the Vienna Canyon Diablo Troilite (V-CDT) standard, and the analytical precision is better than &#177;0.3&#8240;. The sulfur isotope measurements were calibrated with international reference materials: IAEA-S1 (&#948;34S = -0.30&#8240;), IAEA-S2 (&#948;34S = -21.55&#8240;), IAEA-S3 (&#948;34S = -31.4&#8...

Watch this Scientific Journal Video about Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS at JoVE.com

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS

Analyses of the sulfur isotopic composition (&#948;34S) of pyrite from methane-bearing sediments have typically focused on bulk samples. Here, we applied secondary ion mass spectroscopy to analyze the &#948;34S values of various pyrite generations to understand the diagenetic history of pyritization.

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and ...

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Determination of Microbial Extracellular Enzyme Activity in Waters, Soils, and Sediments using High Throughput Microplate Assays

Much of the nutrient cycling and carbon  processing in natural environments occurs through the activity of extracellular  enzymes released by ...

Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) ...

Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

In situ recovery (ISR) is the predominant method of uranium extraction in the United States. During ISR, uranium is leached from an ore body and extracted ...

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

The importance of microbial sulfate reduction relies on the various applications that it offers in environmental biotechnology. Engineered sulfate ...

Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection

Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection

A method for the analysis of dissolved hydrogen sulfide in crude oil samples is demonstrated using gas chromatography. In order to effectively eliminate ...

LC-MS Analysis of Human Platelets as a Platform for Studying Mitochondrial Metabolism

Perturbed mitochondrial metabolism has received renewed interest as playing a causative role in a range of diseases. Probing alterations to metabolic ...

Simultaneous DNA-RNA Extraction from Coastal Sediments and Quantification of 16S rRNA Genes and Transcripts by Real-time PCR

Real Time Polymerase Chain Reaction also known as quantitative PCR (q-PCR) is a widely used tool in microbial ecology to quantify gene abundances of ...

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended ...

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment ...

Bioindication Testing of Stream Environment Suitability for Young Freshwater Pearl Mussels Using In Situ Exposure Methods

Bioindication Testing of Stream Environment Suitability for Young Freshwater Pearl Mussels Using In Situ Exposure Methods

Knowledge of habitat suitability for freshwater mussels is an important step in the conservation of this endangered species group. We describe a protocol ...