Fluids in Continental Fault Zones: Evidence From Neomineralized Clays

大陆断裂带中的流体：来自新矿化粘土的证据

• 批准号: 1118704
• 负责人: Ben van der Pluijm
• 金额: $ 23.04万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1118704&HistoricalAwards=false
• 关键词: Fluids; Continental; Fault; Zones; Evidence

Newly-grown clays in fault rock preserve the isotopic signature of fluids that were present during faulting, and will be used to constrain the plumbing of shallow fault systems and the dominant source of fluids. Examining fluid infiltration and circulation of crustal fault systems tests the hypothesis that fluids originating at the surface are the dominant phase in strike-slip fault and normal fault systems. This research project will use paired oxygen and hydrogen isotopic measurements on newly-grown illite from a suite of detachment (normal) fault systems in southwestern United States and continental strike-slip faults (San Andreas Fault, Alpine Fault, North Anatolian Fault). These faults contain neomineralized clays and are well-studied examples of major continental fault systems. The field approach utilizes surface sampling and recent drill core, while the laboratory works involves stable and radiogenic analyses, supported by various sample characterization studies.Studying fluid circulation in natural fault systems is fundamental to understanding the role of fluids within the upper crust, which has major implications for the strength and seismogenesis of faults, and the formation of economic deposits. The approach in this study can be applied to many fault systems around the world to examine the relative contributions of metamorphic (deep) and meteoric (surface) fluids, so it has excellent potential for broad application. This field and laboratory project includes graduate and undergraduate students at the University of Michigan, and involves international collaboration with several field and laboratory experts. The training of young scientists contributes significantly to tomorrow's needs for human capital in science, math and engineering fields. Results will be published in the professional literature and inserted in appropriate public outreach and teaching setting, as well as scientific presentations by team members.

断层岩中新生长的粘土保留了断层作用期间存在的流体的同位素特征，并将被用来约束浅层断层系统的管道和流体的主要来源。研究地壳断裂系统的流体渗透和循环，验证了走滑断裂和正断层系统中流体起源于地表是主要相态的假设。该研究项目将对美国西南部一套拆离(正)断层系统和大陆走滑断层(圣安德烈斯断层、阿尔卑斯断层、北安纳托利亚断层)中新生长的伊利石进行成对的氧和氢同位素测量。这些断层含有新矿化的粘土，是主要大陆断层系统中研究得很好的例子。野外方法利用地表采样和最近的钻芯，而实验室工作涉及稳定和放射性成因分析，并得到各种样品表征研究的支持。研究天然断裂系统中的流体循环对于了解上地壳内流体的作用是基本的，这对断裂的强度和地震成因以及经济矿床的形成具有重要意义。该方法可应用于世界各地的许多断裂系统，以考察变质(深部)和大气(表层)流体的相对贡献，因此具有很好的应用潜力。这个领域和实验室项目包括密歇根大学的研究生和本科生，并涉及与几个领域和实验室专家的国际合作。对年轻科学家的培训对未来科学、数学和工程领域对人力资本的需求做出了重大贡献。结果将发表在专业文献中，并插入适当的公共宣传和教学环境中，以及小组成员的科学陈述中。