Collaborative Research: Multiple Sulfur Isotope Tracers of the Subsurface Biosphere in Oceanic Basement

合作研究：海洋基底地下生物圈的多种硫同位素示踪剂

• 批准号: 0753126
• 负责人: Shuhei Ono
• 金额: $ 12.83万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0753126&HistoricalAwards=false
• 关键词: Collaborative; Research; Multiple; Sulfur; Isotope

ABSTRACT 0622949/0622982/0623550 (Alt/Rouxel/Ono)Intellectual Merit: Fluids circulate at low temperatures (100C) through the upper oceanic crust on mid ocean ridge flanks and in ocean basins providing vast potential habitats for a subsurface biosphere. This work tests the hypothesis that microbial sulfate reduction occurs in crystalline oceanic basement rocks (basalts and gabbros), and that it is a widespread and important processes affecting the sulfur budget of the oceanic crust. The research plan entails determining the contents and stable isotope ratios of sulfur (S) and selenium (Se) in altered oceanic basement. Specific analyses include ion microprobe analyses of del 34S of individual sulfide grains, whole rock S and Se contents, Se isotopes and multiple-sulfur isotope ratio analyses (del 33S, del 34S and del 36S). The data enable testing for microbial signatures, provide evidence for fluid evolution, help constrain redox conditions and the sources of S in the rocks (remobilized basaltic sulfide or seawater), and aid in understanding the effects of microbial activity on the budget for S during alteration of oceanic basement. The research focuses on upper oceanic basement from well-studied IODP Site U1301, but also includes gabbros from ODP Hole 735B, and limited analyses of other basaltic basement. Results of the work help improve our understanding of microbial activity during alteration of ocean crust, and provide a basis for establishing links between geochemistry and microbiology. Broader Impacts:This research will support two early career scientists and one senior scientist in Washington DC, Massachusetts, and Michigan, respectively. The research is multi-institutional and will engage undergraduates in research. The work leverages NSF investments by using samples collected by the NSF-Ocean Drilling program.

摘要0622949/0622982/0623550（ALT/ROUXEL/ono）智力优点：流体在低温（100c）中通过中海山脊侧面的海洋壳（100c）循环，在海洋山脊侧面，在海洋盆地为地下BioSphere提供巨大的潜在栖息地。这项工作检验了以下假设：硫酸硫酸盐还原发生在晶体的海底岩石（玄武岩和加布布罗斯）中，并且它是影响海洋壳硫预算的广泛而重要的过程。该研究计划需要确定硫酸盐（S）和硒（SE）的含量和稳定的同位素比。 具体分析包括对单个硫化物晶粒，整个岩石和SE含量，SE同位素和多硫同位素比分析的DEL 34s的离子微探针分析（DEL 33S，DEL 34S和DEL 36S）。该数据实现了微生物特征的测试，提供了液体演化的证据，有助于限制氧化还原条件和岩石中的S来源（重新植入碱性硫化物或海水），并有助于了解海洋基质改变过程中微生物活动对S的影响。该研究的重点是研究经过良好的IODP站点U1301的上海底，但还包括来自ODP孔735B的Gabbros，以及对其他玄武岩基底的分析有限。 这项工作的结果有助于提高我们对海壳改变过程中微生物活性的理解，并为建立地球化学与微生物学之间的联系提供了基础。更广泛的影响：这项研究将分别支持华盛顿特区，马萨诸塞州和密歇根州的两名早期职业科学家和一名高级科学家。 这项研究是多机构的，将吸引本科生参与研究。 这项工作通过使用NSF-Ocean钻探计划收集的样本来利用NSF投资。