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

从拟议的研究结果将产生新的同位素测量从重晶石，一个高度稳定和广泛分布的矿物中发现的岩浆，变质和沉积岩的所有年龄，以及在土壤，气溶胶尘埃，和外星物质。重晶石Sr稳定同位素分馏控制参数的确定，将为地球化学、水文地质、热液、古环境等地质环境研究开辟新的途径。这一基础性研究将为今后在地球科学中使用重晶石中的质量相关Sr同位素测量奠定基础。重晶石可能是一个理想的工具，以解决地球科学中的关键问题，包括早期地球地球化学，在外星样品中的潜在生命的证据，重建的温度在地层流体，如泉水和渗漏，水岩相互作用，跟踪大气输入到土壤的来源，重建全球变化的Sr 2+预算在地球？世界上很少有实验室已经开发出测量稳定Sr同位素比的方法;这里提出的这种新的稳定同位素系统的工作将提供一个独特的机会，有助于这种新的同位素系统在其开始阶段的发展。研究生和本科生将有机会在这个研究项目的多个实验室工作和互动（在肯特州立大学，南加州大学，阿克伦大学，加州大学洛杉矶分校，俄克拉荷马州大学），从而发展和指导研究和分析技能。他们将进行仔细的实验，在俄克拉荷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西部和北方犹他州的现场进行互动。将通过一个出版的实践学习模块在当地高中开展外联活动，该模块调查了教育的基本概念。温室效应？并将聘请我们目前的地质学生参观他们的老高中，并转达他们对地球科学作为未来职业的兴奋。

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.