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.

确定地质物质的年龄（地质年代学）是了解地球历史的基础。氨基酸消旋化（AAR）年代学是一种适用于各种化石类型、沉积环境和时间尺度的测年方法。它可以研究广泛的地球科学主题，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：利用有孔虫对海洋沉积物岩心进行测年。将测试各种方法以减少分析变异性，这是AAR地质年代学应用于有孔虫时的主要误差来源。几个广泛存在的有孔虫类群将受到化学预处理，以分离出不太容易受到沉积后环境影响的氨基酸的一部分。一旦优化，该处理将应用于地层参考层网络的样本，这些样本来自年代确定的深海岩心。这些数据将用于评价各遗址间AAR年代学的可重复性，并校准几个参考物种的外消旋速率。其他地点的样品将用于量化不同地热梯度对有孔虫外消旋程度的可能影响。将采用最近开发的数据分析方法来模拟随时间变化的外消旋化率，并描述年龄不确定性。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。

项目成果

Testing the effect of oxidizing pre-treatments on amino acids in benthic and planktic foraminifera tests

在底栖和浮游有孔虫测试中测试氧化预处理对氨基酸的影响

• DOI: 10.1016/j.quageo.2022.101401
• 发表时间: 2022
• 期刊: Quaternary Geochronology
• 影响因子: 2.7
• 作者: Millman, Emily;Wheeler, Lucy;Billups, Katharina;Kaufman, Darrell;Penkman, Kirsty E.H.
• 通讯作者: Penkman, Kirsty E.H.

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
• 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.

Can amino acid racemization be utilized for fish age validation?

• DOI: 10.1139/cjfas-2022-0161
• 发表时间: 2023-02-01
• 期刊: CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
• 影响因子: 2.4
• 作者: Chamberlin, Derek W.;Shervette, Virginia R.;Patterson III, William F.
• 通讯作者: Patterson III, William F.

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
• 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.

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
• 期刊: Sedimentary Geology
• 影响因子: 2.8
• 作者: Kindler, Pascal;Hearty, Paul J.
• 通讯作者: Hearty, Paul J.