Collaborative Research: Characterizing the Regional Fluid Flow System of the Wyoming Salient, Sevier Fold-Thrust Belt: Implications for Orogenic Wedge Deformation and Propagation

该项目的目标是研究地壳流体在形成美国西部科迪勒兰褶皱和冲断带的典型怀俄明凸起的变形过程中所起的作用。科迪勒拉造山带是约1.4 ~ 5000万年前塞维耶造山运动时期法拉龙板块向北美板块俯冲而形成的会聚边缘构造活动，是由褶皱和断裂组成的主要构造特征。怀俄明凸起被认为是进行这项研究的理想地点，因为它已经被广泛研究，并且是世界上最具特征的褶皱和冲断带之一。该项目的结果将提供关于流体如何促成与造山事件、断裂带过程相关的大规模变形的见解，并且结果将对具有社会相关性的各种学科产生影响，包括矿物勘探、碳氢化合物勘探、水文学。除了该项目的研究目标外，该项目还将有助于培养STEM学科的研究生和本科生；三所大学合作；对博士学位授予机构和初级本科院校的研究基础设施的贡献；将研究成果纳入课堂课程；通过同行评议的出版物、专业地球科学会议上的报告以及可通过网络访问的数字数据集传播研究成果。该项目将创新地整合详细的构造、流体包裹体、稳定同位素和地质年代学研究，这些研究沿着弯曲的怀俄明凸起的横断面进入前陆，沿着关键的大型褶皱和主要断裂带的穿越，提供广泛的新的区域数据集，将流体流动与渐进变形联系起来。虽然以前的实验室研究已经提供了变形微观机制的见解，并且以前的冲断带的现场和建模研究已经揭示了断裂带和不断演变的地形对流体流动系统的重要性，但区域到局部流体流动与扩展的褶皱-冲断楔内渐进变形之间的定量相互关系仍然知之甚少。该项目将建立在先前对怀俄明州凸起的结构研究的基础上，并将结果综合起来，以提高我们对流体流动和推力楔力学之间反馈的理解。该项目将测试弯曲褶皱冲断带内流体流动系统的模型，包括微观、中观和宏观流体路径的性质；降水、地层水和变质水在地形楔状递进扩展和发展过程中的变化贡献地层演化与流体流动的构造分型：变形方式由分布的层平行缩短转变为集中的逆冲滑动；拆离断裂的扩展和褶皱-逆冲楔前缘早期层平行缩短与流体流动增强和埋藏有关。该项目将建立在先前在怀俄明州凸起的结构研究的基础上，并将结果综合起来，以提高我们对流体流动和楔形力学之间反馈的理解。该项目将结合多种方法，包括细观结构分析和采样静脉/裂缝集、解理和提供流体通道的小断层，

The goal of this project is to investigate the role that crustal fluids have played in deformational processes that created the classic Wyoming salient of the Cordilleran fold and thrust belt of the western United States. The Cordilleran orogenic belt is a major tectonic feature consisting of folds and faults that resulted from convergent margin tectonic activity due to subduction of the Farallon plate beneath the North American plate about 140 to 50 million years ago during the Sevier Orogeny. The Wyoming salient is considered to be an ideal place for this study given that it has been extensively studied and is of the best characterized fold and thrust belts in the world. The results of the project will provide insights into how fluids contribute to large-scale deformation associated with mountain building events, fault zone processes, and the results will have implications for a variety of disciplines that have societal relevance, including mineral exploration, hydrocarbon exploration, hydrology. In addition to the research goals of the project, the project will contribute to training of graduate and undergraduate students in a STEM discipline; collaboration between three universities; contributions to research infrastructure at at Ph.D. granting and primary undergraduate institutions; incorporation of research results into classroom curricula; and dissemination of research results via peer-reviewed publications, presentations at professional geoscience meetings, and by web accessible digital data sets. This project will innovatively integrate detailed structural, fluid inclusion, stable isotope, and geochronologic studies along transects across the curved Wyoming salient into the foreland and along traverses of key large-scale folds and major fault zones, providing extensive new regional data sets that relate fluid flow with progressive deformation. Although previous laboratory studies have provided insights into deformation micromechanisms and previous field and modeling studies of thrust belts have revealed the importance of fault zones and evolving topography on fluid flow systems, quantitative interrelations between regional to local fluid flow and progressive deformation within propagating fold-thrust wedges remains poorly understood. This project will build on previous structural studies in the Wyoming salient, with results synthesized to improve our understanding of feedbacks between fluid flow and thrust wedge mechanics. The project will test models of fluid-flow systems within curved fold-thrust belts, including nature of micro-, meso-, and megascopic fluid pathways; changing contributions of meteoric-, formation-, and metamorphic-waters during progressive wedge propagation and development of topography; evolving stratigraphic and structural compartmentalization of fluid flow as deformation changes style from distributed layer-parallel shortening to concentrated thrust slip; and propagation of detachment faults and early layer-parallel shortening in front of the fold-thrust wedge related to enhanced fluid flow and burial. This project will build on previous structural studies in the Wyoming salient, with results synthesized to improve our understanding of feedbacks between fluid flow and wedge mechanics. The project will combine a variety of methodologies, including mesoscopic structural analysis and sampling of veins/fracture sets, cleavage, and minor faults that provided fluid pathways,