Rates, timing, & nature of sub-orbital sea-level change during MIS 5e

价格、时间、

• 批准号: 1559040
• 负责人: David Foster
• 金额: $ 50.39万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-15 至 2021-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1559040&HistoricalAwards=false
• 关键词: Rates; timing; & nature; sub

Projections for the magnitude and rate of sea-level change in the future are highly dependent on ice sheet models that simulate the response of the polar ice sheets to sustained warming. Unfortunately, the physics associated with ice sheet collapse is not fully understood, requiring a different approach to estimate future ice sheet response. This project seeks to quantify rates of sea-level change during a past warm period known as the last interglacial, ~125,000 years ago. This information can then be used to constrain our projections of the rate of future sea-level rise. In particular, the principal investigator will investigate the rate of sea-level changes during this past warm period associated with meter-scale sea-level oscillations. The oscillations have been inferred from the features observed in sedimentary records from around the globe that suggest a dynamic instability in polar ice sheets during the warm period. The project includes student training and education (Ph.D. and masters students, and undergraduate students). A marine science class from the University of Florida will go to a sampling site in southern Florida to gain valuable field experience. There is strong international collaboration between the principal investigator, U.S. students, and researchers from Mexico and Australia. Joint support for U.S. students to collaborate with researchers from Australia was provided by the Office of International Science and Engineering.This project will address existing debates regarding the timing and nature of sea-level oscillations during Marine Isotope Stage (MIS) 5e. The approach is to study several key fossil reef sequences around the globe using a multidisciplinary approach that combines detailed analysis of taphonomy, diagenesis, reef assemblages, paleowater depth indicators, carbonate sedimentology and petrography, stratigraphy, glacial isostatic adjustment, surveying, and geochemical and geochronological data. Conventional bulk U-Th analyses will be complemented with laser ablation U-Th ages to investigate micro-scale carbonate phases and to evaluate spatial scales of preservation within the samples.

未来海平面变化幅度和速率的预测高度取决于模拟冰盖模型，这些模型模拟了极地冰盖对持续变暖的响应。 不幸的是，与冰片崩溃相关的物理学尚未完全了解，需要采用不同的方法来估计未来的冰盖反应。该项目旨在量化在过去的温暖时期，即最后的冰河间冰期变化率，〜125，000年前。 然后，这些信息可用于限制我们对未来海平面上升速度的预测。 特别是，首席研究人员将调查与仪表尺度海平面振荡有关的过去温暖时期的海平面变化率。 振荡是从全球沉积记录中观察到的特征推断出来的，这些特征表明在温暖时期，极地冰盖的动态不稳定性。该项目包括学生培训和教育（博士学位和硕士学生，以及本科生）。佛罗里达大学的海洋科学课将前往佛罗里达州南部的一个抽样场所，以获得宝贵的实地经验。 来自墨西哥和澳大利亚的主要研究人员，美国学生和研究人员之间有强有力的国际合作。国际科学与工程办公室提供了对美国学生与澳大利亚研究人员合作的共同支持。该项目将解决有关海洋同位素阶段（MIS）5E期间海平面振荡时间和性质的现有辩论。 该方法是使用多学科的方法研究全球几个关键的化石礁序列，该方法结合了对taphonomy，成岩作用，礁石组合，古生物学深度指标，碳酸盐沉积学和岩石学，地层，冰川层次，冰川等静态调整，测量，测量，测量，以及金属学数据的详细分析。 常规的大量U-TH分析将与激光消融U-The Ages相辅相成，以研究微型碳酸盐阶段并评估样品中的空间保存量表。