Development of New Techniques: Sustaining and sharpening amino acid geochronology

新技术的开发：维持和加强氨基酸地质年代学

• 批准号: 1855381
• 负责人: Darrell Kaufman
• 金额: $ 30.81万
• 依托单位: Northern Arizona University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1855381&HistoricalAwards=false
• 关键词: Development; New; Techniques; Sustaining; sharpening

Determining the ages of geological materials (geochronology) is fundamental to understanding Earth's history. Amino acid racemization (AAR) geochronology is a dating method applicable to a wide range of fossils types, depositional environments, and time scales. It enables research in a broad range of geoscience topics such as archeology, historical ecology, paleontology, tectonic geomorphology, paleoceanography, glacial geology, and others. This award will support scientific infrastructure by sustaining the laboratory for AAR geochronology at Northern Arizona University. This project will sharpen one of the most outstanding untapped applications of AAR geochronology: as a dating method for marine sediment cores using foraminifera. Various procedures will be tested to reduce analytical variability, a major source of error for AAR geochronology when applied to foraminifera. Several widely occurring foraminifera taxa will be subjected to chemical pre-treatments to isolate a fraction of amino acids that is less prone to post-depositional environmental influences. Once optimized, the treatment will be applied to samples from a network of stratigraphic reference horizons from well-dated deep-sea cores. The data will be used to evaluate the reproducibility of AAR geochronology among the sites and to calibrate the rate of racemization for several reference species. Samples from other sites will be used to quantify the possible influence of different geothermal gradients on the extent of racemization in foraminifera. Recently developed data-analytical approaches will be employed to model the time-dependent rate of racemization and to characterize age uncertainties.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.

确定地质材料的年龄（地质年代学）是了解地球历史的基础。氨基酸外消旋 (AAR) 地质年代学是一种适用于多种化石类型、沉积环境和时间尺度的测年方法。它支持广泛的地球科学主题的研究，如考古学、历史生态学、古生物学、构造地貌学、古海洋学、冰川地质学等。该奖项将通过维持北亚利桑那大学 AAR 地质年代学实验室来支持科学基础设施。该项目将强化 AAR 地质年代学最突出的未开发应用之一：作为使用有孔虫的海洋沉积物岩心的测年方法。将测试各种程序以减少分析变异性，这是 AAR 地质年代学应用于有孔虫时的主要误差来源。几种广泛存在的有孔虫类群将接受化学预处理，以分离出不易受到沉积后环境影响的一小部分氨基酸。经过优化后，该处理将应用于来自已定年的深海岩心的地层参考层网络中的样本。这些数据将用于评估各个地点之间 AAR 地质年代学的再现性，并校准几个参考物种的外消旋率。来自其他地点的样品将用于量化不同地温梯度对有孔虫外消旋化程度的可能影响。最近开发的数据分析方法将用于模拟外消旋的时间依赖性速率并描述年龄不确定性。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

NOAA/WDS Paleoclimatology - Yermak Plateau, Arctic Ocean 227ka Foraminifer Amino Acid Racemization Data

NOAA/WDS 古气候学 - 北冰洋耶尔马克高原 227ka 有孔虫氨基酸外消旋化数据

• DOI: 10.25921/0dny-d516
• 发表时间: 2019-01
• 期刊: NOAA National Centers for Environmental Information
• 作者: West, G.;Kaufman, D.S.;Muschitiello, F.;Forwick, M.;Matthiessen, J.;Wollenburg, J.;O'Regan, M.
• 通讯作者: O'Regan, M.

The Whale Point Formation: A stratigraphic record of high-frequency climate and sea-level fluctuations in the Bahamas during Marine Isotope Stage 5a (ca. 80 ka BP)

鲸鱼点地层：海洋同位素阶段 5a（约 80 ka BP）期间巴哈马高频气候和海平面波动的地层记录

• DOI: 10.1016/j.sedgeo.2022.106107
• 发表时间: 2022-04
• 期刊: Sedimentary Geology
• 影响因子: 2.8
• 作者: Kindler, Pascal;Hearty, Paul J.
• 通讯作者: Hearty, Paul J.

NOAA/WDS Paleoclimatology - Quaternary Arctic Ocean Foraminifer Amino Acid Racemization Data

NOAA/WDS 古气候学 - 第四纪北冰洋有孔虫氨基酸外消旋化数据

• DOI: 10.25921/bx56-4d69
• 发表时间: 2023-01
• 期刊: NOAA National Centers for Environmental Information
• 作者: West, G.;Kaufman, D.S.;Jakobsson, M.;O'Regan, M.
• 通讯作者: O'Regan, M.

COMPARING DIRECT CARBONATE AND STANDARD GRAPHITE 14 C DETERMINATIONS OF BIOGENIC CARBONATES

比较直接碳酸盐和标准石墨 14 C 测定生物碳酸盐的方法

• DOI: 10.1017/rdc.2020.131
• 发表时间: 2021-04
• 期刊: Radiocarbon
• 影响因子: 8.3
• 作者: Bright, Jordon;Ebert, Chris;Kosnik, Matthew A;Southon, John R;Whitacre, Katherine;Albano, Paolo G;Flores, Carola;Frazer, Thomas K;Hua, Quan;Kowalewski, Michal;et al
• 通讯作者: et al

Millennial‐Scale Age Offsets Within Fossil Assemblages: Result of Bioturbation Below the Taphonomic Active Zone and Out‐of‐Phase Production

化石组合内的千禧年尺度年龄偏移：埋藏活动区以下生物扰动和阶段外生产的结果

• DOI: 10.1029/2018pa003553
• 发表时间: 2019-06
• 期刊: Paleoceanography and Paleoclimatology
• 影响因子: 3.5
• 作者: Tomašových, A.;Kidwell, S. M.;Alexander, C. R.;Kaufman, D. S.
• 通讯作者: Kaufman, D. S.