RUI Collaborative Research: Experimental Investigation of Fluid-Rock Interaction in Back-Arc Environments

RUI 合作研究：弧后环境中流体-岩石相互作用的实验研究

• 批准号: 0732478
• 负责人: Jeffrey Seewald
• 金额: $ 17.99万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-10-01 至 2011-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0732478&HistoricalAwards=false
• 关键词: RUI; Collaborative; Research; Experimental; Investigation

Recent cruise results from the Lau back-arc basin documents hydrothermal fluid compositions that differ greatly from the well-studied vents along the global Mid-Ocean Ridge (MOR) system. Moreover, systematic local and regional variations in fluid composition within this back-arc environment have also been observed. Back-arc hydrothermal systems are likely controlled by a number of unique geologic variables, including the presence of felsic volcanic rocks in the subsurface and the much greater likelihood that fluids of magmatic origin contribute to fluid composition. It is these complex geologic factors that likely account for both the large differences between MOR and back-arc hydrothermal fluids and the regional variations in fluid composition observed within a single back-arc system. As a consequence of these complexities, models for the origin and evolution of hydrothermal fluids in back-arc environments are, at present, poorly constrained because the chemical processes associated with the reaction of seawater-derived hydrothermal fluids and volcanic rocks of felsic composition have not been systematically studied. This study is a laboratory investigation of the specific chemical processes that occur during the interaction of seawater-derived hydrothermal fluids with rocks of andesitic, dacitic, and rhyolitic compositions. These experiments will provide fundamental information necessary to identify key processes that regulate fluid chemistry in back-arc hydrothermal systems. The Lau Basin has been designated as a RIDGE Integrated Study Site and the proposed research will further our understanding of this complex hydrothermal environment.This NSF-RUI investigation is a novel integration of research and education through a laboratory-based collaboration between the Woods Hole Oceanographic Institution (WHOI) and Bridgewater State College (BSC). The project will allow Dr. Saccocia to conduct laboratory-based research relevant to the RIDGE initiative and thereby participate in cutting-edge research that would not otherwise be possible without a WHOI collaborator. Second, the research agenda will form the basis of an undergraduate research course in Earth Science at BSC. This course will enroll anywhere from 5-10 students and will be offered each spring semester over the three year grant period. Each student will 1) read relevant articles from the peer-reviewed literature to learn about the background of the proposed research, 2) actively participate in the analytical work (at WHOI) associated with the experiments by working in teams, 3) interpret the results as the data is generated, 4) write reports describing the significant scientific results from their analytical team, and 5) contribute to the production of a single manuscript that emulates the format of a journal article. Thus, this RUI grant will provide a unique undergraduate research experience for up to 30 geology students at BSC, making them more competitive applicants to high quality graduate programs and enhancing the likelihood that they will pursue careers in the geosciences. In addition to the research course, this project provides an opportunity for up to 6 undergraduate students at BSC to perform more intensive research in the hydrothermal laboratory at WHOI during the summer months.

LAU后弧盆地的最新巡航结果是水热液组成，与全球中洋山脊（MOR）系统沿线的通风孔有很大不同。此外，还观察到了这种背弧环境中流体组成的系统局部和区域变化。后弧热液系统可能受到许多独特的地质变量的控制，包括地下存在长英质火山岩，而岩浆起源流体有助于流体成分的可能性更大。正是这些复杂的地质因素可能解释了MOR和后弧水热流体之间的巨大差异以及在单个后弧系统中观察到的流体组成的区域变化。由于这些复杂性，目前，在背弧环境中水热液的起源和演变模型受到了较低的约束，因为与海水衍生的水热液和felsic岩的反应相关的化学过程尚未尚未被系统地研究了。这项研究是对海水衍生的水热液与安第斯山岩，二酸和流纹岩组成的岩石相互作用期间发生的特定化学过程的实验室研究。这些实验将提供必要的基本信息，以确定调节后弧水热系统中流体化学的关键过程。 Lau盆地已被指定为脊综合研究地点，拟议的研究将进一步了解这一复杂的热液环境。这项NSF-RUI调查是通过伍兹孔海洋学之间的基于实验室的合作进行研究和教育的新型整合。机构（WHOI）和布里奇沃特州立大学（BSC）。该项目将使Saccocia博士能够进行与Ridge Initiative相关的基于实验室的研究，从而参与尖端研究，而没有Whoi合作者，否则就不可能。其次，研究议程将构成BSC地球科学本科研究课程的基础。本课程将在5-10名学生中注册，并将在每个春季学期提供三年的赠款期。每个学生将1）阅读同行评审的文献中的相关文章，以了解拟议研究的背景，2）积极参与与实验相关的分析工作（在WHOI），通过团队合作，3）解释结果。随着数据的生成，4）写报告，描述了其分析团队的重要科学结果，5）有助于产生模拟期刊文章格式的单手稿。因此，这项RUI赠款将为BSC的最多30名地质学生提供独特的本科研究经验，使他们更有竞争力的申请人在高质量的研究生课程中，并增强了他们从事地球科学的职业的可能性。除研究课程外，该项目为BSC的最多6名本科生提供了一个机会，可以在夏季在WHOI的热液实验室进行更深入的研究。