CAREER: Organic Molecular Paleohypsometry: A new approach to quantifying the topographic history of the most rapidly eroding mountain belt on Earth

地球构造板块的运动控制着山脉的形成，影响着地震的频率和震级，并影响着负责形成油气藏的碳的运输和埋藏。尽管山区在形成地质灾害、沉积物输出和全球环境条件方面至关重要，但几乎没有办法量化其随时间的增长。该项目的重点是开发一种新的工具，以量化将对地球物理学、石油和天然气工业以及地表变化研究产生影响的山脉古海拔变化。该项目通过为STEM核心学科的研究生培训提供支持，为具有全球竞争力的STEM（科学，技术，工程和数学）劳动力的发展做出贡献，从而造福社会。进一步的社会效益包括通过与哈特福德地区STEM Magnate学校建立新的STEM教育推广合作，支持将地球科学教育纳入康涅狄格州科学标准，该学校为大多数少数民族人口提供服务。这个外展计划，题为“山，河流和碳”，提供传统上代表性不足的学生动手接触地球科学研究，与首席研究员的日常接触，并有机会让学生参加在康涅狄格州校园的大学，桥梁采样在现代河流中的活动在工作实验室和大学教师和学生的参与研讨会。这项研究还促进了美国和台湾科学家之间新的国际合作的发展。 本研究是基于沉积档案中保存的有机质的同位素化学，开发一种新的地球化学工具来重建山区带的古高程历史。这种方法，题为有机分子古重力仪，利用水和有机物的稳定同位素组成的测量和可预测的变化作为海拔的函数。来源于不同海拔的有机质具有不同的稳定同位素特征，沉积有机质同位素化学的变化应反映源区综合海拔的变化。台湾是地球仪上隆起和侵蚀最快的地区之一，但迄今为止还没有古高程技术适用于台湾。此方法的校正包括从台湾各地的现代河流沃茨、土壤和沉积物中取样，以量化河流沉积物中有机物质的同位素化学如何反映山区汇水区有机物质的化学。这种方法将被应用到地质最近的海洋和陆地洪泛平原沉积物岩心从高坪河和海底峡谷，以检查在最近的晚更新世全球冰川消退的有机分子特征的短时间尺度的影响。此外，这项研究计划将重点放在分析台湾西部沿着盆地的500万年及更年轻的沉积物，以检验台湾造山带的有机分子记录是否显示它是沿着台湾岛的长度沿着同时隆起的，或者在过去的150万年里经历了向南的高地形传播。这个奖项反映了NSF的法定使命，并被认为是值得支持的通过使用基金会的知识价值和更广泛的影响审查标准进行评估。

Movement of Earth's tectonic plates controls the formation of mountains, affects the frequency and magnitudes of earthquakes and influences the transport and burial of carbon responsible for the formation of hydrocarbon reservoirs. Despite the critical importance of mountains in shaping geologic hazards, sediment export and global environmental conditions, there are few ways of quantifying their growth over time. This project is focused on development of a new tool to quantify changes in the paleoelevation of mountains that will have implications for geophysics, the oil and gas industry and studies of surface change. This project benefits society by contributing to the development of a globally competitive STEM (science, technology, engineering and mathematics) work force by providing support for graduate student training in a core STEM discipline. Further societal benefits include support for the integration of earth science education into Connecticut State Science Standards through the creation of a new STEM education outreach collaboration with Hartford area STEM Magnate schools that serve a majority minority population. This outreach program, entitled "Mountains, Rivers and Carbon", provides traditionally-underrepresented students with hands-on exposure to earth science research, routine engagement with the principal investigator, and opportunities for students to participate in a workshop at the University of Connecticut campus that bridges sampling in a modern river with activities in a working lab and engagement with university faculty and students. The research is also fostering the development of new international collaborations between U.S. and Taiwan scientists. This research is developing a new geochemical tool to reconstruct the paleoelevation history of mountain belts based on the isotope chemistry of organic matter preserved in sedimentary archives. This method, entitled Organic Molecular Paleohypsometry, exploits the measured and predictable variation in the stable isotope composition of water and organic matter as a function of elevation. Organic matter sourced from different elevations is characterized by distinct stable isotopic signatures, and changes in the isotope chemistry of sedimentary organic matter should reflect changes in the integrated elevation of the source area. The method is being tested, refined and applied to Taiwan, one of the fastest uplifting and eroding regions of the globe, but a region for which no paleoelevation technique has been applicable, until now. Calibration of this method includes sampling of modern river waters, soils and sediments from across Taiwan to quantify how the isotope chemistry of organic matter in river sediments reflects the chemistry of organic material from across mountainous catchments. This approach will be applied to geologically-recent marine and terrestrial floodplain sediment cores from the Gaoping river and submarine canyon to examine short-timescale effects on organic molecular signatures during the recent late Pleistocene global deglaciation. In addition, the proposed research focuses on the analysis of 5 million year and younger sediments from basins along western Taiwan to test whether organic molecular records of the Taiwan orogen show that it was uplifted simultaneously along the length of the island, or experienced a southward propagation of high topography over the last 1.5 million years.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.