EAR-PF: RECALIBRATING THE SILURIAN SYSTEM USING INTEGRATED HIGH-RESOLUTION BIOCHEMOSTRATIGRAPHY AND GEOCHRONOLOGY: A CASE STUDY FOR THE PALEOZOIC ERA

布拉德利·克雷默博士获得了美国国家科学基金会地球科学博士后奖学金，将在堪萨斯地质调查局和堪萨斯大学开展一项研究和教育计划。拟议的研究将进行一项调查，以显著改进志留纪的时间尺度(4.44亿至4.16亿年前)，并更好地限制我们对古生代全球气候变化速度(5.42亿至2.51亿年前)的理解。该项目将综合牙形石和笔石的高分辨率生物地层学、高分辨率碳酸盐碳同位素化学地层学、新的单颗粒锆石U/Pb年龄测定和轨道调谐的平均光谱失配(ASM)方法，以产生分辨率和保真度接近现代全球气候记录的志留纪时间尺度。拟议的研究将包括来自美国、英国、瑞典和爱沙尼亚的研究区。这项拟议的研究将使地质时间刻度的志留纪部分的分辨率提高一个数量级以上，完成后，将标志着我们在数千年尺度的远古时代判断时间的能力方面有了重大改进。将地球的深层气候历史分解为如此短的时间尺度将使5亿多年的全球气候变化能够直接影响我们对现代气候系统的理解，并大大提高我们对海洋-大气系统内自然变异性的理解。研究方法和结果将被整合到课程材料中，由KU地质系的PI教授，研究生和本科生都将包括在拟议研究的实地和实验室部分，为学生提供实践培训。

Dr. Bradley Cramer has been granted an NSF Earth Sciences Postdoctoral Fellowship to carry out a research and education plan at the Kansas Geological Survey and the University of Kansas. The proposed research will undertake an investigation to significantly improve the Silurian timescale (444 to 416 million years ago) and better constrain our understanding of the rates of Paleozoic global climate change (542 to 251 million years ago). This project will integrate high-resolution biostratigraphy of conodonts and graptolites, high-resolution carbonate carbon isotope chemostratigraphy, new single grain zircon U/Pb age dates, and the Average Spectral Misfit (ASM) method of orbital tuning to produce a Silurian timescale with resolution and fidelity approaching that of modern global climate records. The proposed research will include study areas from the United States, the United Kingdom, Sweden, and Estonia. The proposed research will increase the resolution of the Silurian portion of the Geologic Timescale by more than an order of magnitude, and when completed, will mark a significant improvement in our ability to tell time in the deep past, at the scale of thousands of years. Resolving the deep-time climate history of the Earth to such short timescales would allow over 500 million years of global climate change to be directly brought to bear on our understanding of the modern climate system and significantly improve our understanding of the natural variability within the ocean-atmosphere system. Research methods and results will be integrated into course material to be taught by the PI at the KU, Department of Geology, and both graduate and undergraduate students will be included in the field and laboratory portions of the proposed research to provide hands-on training for students.