Collaborative Research: Stable strontium isotope ratios (88/86Sr) in abiotic and microbially mediated barite

拟议研究的结果将从重晶石中产生新的同位素测量方法，重晶石是一种高度稳定且广泛分布的矿物，存在于岩浆岩、变质岩和沉积岩中，也存在于土壤、气溶胶尘埃和地外物质中。重晶石中sr同位素稳定分选控制参数的建立，将为地球化学、水文地质、热液和古环境等地质环境研究开辟一条新的途径。这项基础研究将为未来在地球科学中使用重晶石中依赖质量的Sr同位素的测量奠定基础。重晶石可能是解决地球科学关键问题的理想工具，包括早期地球生物地球化学，地外样本中潜在生命的证据，地层流体（如泉水和渗漏）温度的重建，水岩相互作用，追踪大气输入土壤的来源，以及重建地球形成期间Sr2+预算的全球变化。年代的过去。世界上很少有实验室开发出测量稳定sr同位素比率的方法；在这里提出的这个新的稳定同位素系统的研究将提供一个独特的机会，在这个新的同位素系统的开始阶段为其发展做出贡献。研究生和本科生将有机会在这个研究项目的多个实验室（肯特州立大学、南加州大学、阿克伦大学、加州大学洛杉矶分校、俄克拉荷马大学）工作和互动，从而发展和指导研究和分析技能。他们将进行仔细的实验，在俄克拉何马州西部的一个已建立的现场收集样本，并与参与该项目的学生以及科罗拉多州西部和犹他州北部的现场进行互动。将通过出版的实践学习模块在当地高中开展外展活动，该模块调查了？温室效应?并将雇用我们现在的地质学学生去参观他们以前的高中，并传达他们对地球科学作为未来职业的兴奋之情。

Results from the proposed research will generate novel isotope measurements from barite, a highly stable and widely-distributed mineral found in magmatic, metamorphic, and sedimentary rocks of all ages, as well as in soils, aerosol dust, and extraterrestrial material. Establishing the controlling parameters of stable Sr-isotopic fractionation in barite will open a new avenue for geological and environmental research including geochemical, hydrogeological, hydrothermal, and paleoenvironmental studies. This fundamental research will lay the groundwork for future studies in the earth sciences using measurements of mass dependent Sr isotopes in barite. Barite may be an ideal vehicle to address critical questions in the earth sciences, including early earth biogeochemistry, evidence of potential life in extraterrestrial samples, reconstruction of temperatures in formation fluids such as springs and seeps, water rock interactions, tracking provenances of atmospheric inputs into soils, and reconstructing global changes in Sr2+ budgets during earth?s past.Very few laboratories in the world have developed methods to measure stable Sr-isotope ratios; and work on this new stable isotopic system proposed here will provide a unique opportunity to contribute to the development of this new isotope system in its beginning stages. Graduate and undergraduate students will have the opportunity to work and interact in multiple laboratories on this research project (at Kent State Univ., USC, Univ. of Akron, UCLA, Univ. of Oklahoma) thus developing and mentoring research and analytical skills. They will conduct careful experiments, collect samples in the field at an established field site in western Oklahoma and interact with students involved in this project as well as field sites in western Colorado and northern Utah. Outreach activities in local high schools will be established through a published hands-on learning module which investigates fundamental concepts of the ?greenhouse effect? and will employ our current geology students to visit their old high schools and relay their excitement for the geosciences as a future career.