Precipitation of Trace Elements and Stable Isotopes in Reef Corals: a Process Study of Species, Growth Rate, and Diagnetic Influence

礁珊瑚中微量元素和稳定同位素的沉淀：物种、生长速率和诊断影响的过程研究

• 批准号: 9116289
• 负责人: Glen Shen
• 金额: $ 16.07万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-10-15 至 1994-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9116289&HistoricalAwards=false
• 关键词: Precipitation; Trace; Elements; Stable; Isotopes

Of all the mineral phases found in the marine environment, carbonates of various biological origins have proven to be the richest repository of paleoceanographic/paleoclimatic information. Two classes of chemical indicators, stable isotopes and trace elements, have been developed in two principal host phases, foraminiferal calcite and coral aragonite. As biological systems, however, foraminifera and reef corals are capable of leaving metabolic imprints on top of chemical signals which record environmental change. The nature of these imprints must be understood to accurately reconstruct oceanic conditions during Earth's history. Over the last several decades, a process framework has evolved to permit the interpretation of such signals in ancient foraminifera. The intent of this proposal is to initiate a similar framework for metal incorporation by corals. 4 fundamental process issues and their effect on metal (including Cd, Mn, Pb, V, Ba, U) and isotopic precipitation (18O and 13C) will be addressed in this work: (1) growth rate, (2) species variability, (3) reef spatial variability, and (4) digenetic influences on thousand year timescales, taking advantage of existing samples and the ease of cross dating short growth intervals within specimens from a single reef to form detailed comparisons. This approach offers many advantages to a difficult and costly culturing study. Numerous species collected live from Pacific, Atlantic, and Caribbean sites will form the sample basis. The diagenesis study component will utilize precisely dated (U-Th) materials from Barbados to address the feasibility of interpreting Pleistocene trace metal records in fossil corals.

在海洋环境中发现的所有矿物相中， 各种生物来源的碳酸盐已被证明是 最丰富的古海洋/古气候资料库 信息. 两类化学指示剂，稳定同位素 和微量元素，已在两个主要宿主中开发 相、有孔虫方解石和珊瑚文石。 作为生物 系统，然而，有孔虫和珊瑚礁能够 在化学信号上留下代谢印记 记录环境变化。 这些印记的性质 可以准确地重建海洋条件， 地球的历史 在过去的几十年里， 框架已经发展到允许这样的解释 古有孔虫的信号 这项建议的目的是 以引发类似的金属结合框架， 珊瑚 4个基本工艺问题及其对金属的影响（包括 Cd、Mn、Pb、V、Ba、U）和同位素沉淀（18 O和13 C） 在这项工作中将解决：（1）增长率，（2） 物种变异，（3）礁空间变异，（4） 对千年时间尺度的影响， 现有样本的优势和交叉测年的便利性 从一个单一的珊瑚礁标本的生长间隔，形成 详细比较。 这种方法提供了许多优点， 困难和昂贵的培养研究。 收集了许多物种 来自太平洋、大西洋和加勒比地区的现场直播将构成 抽样基础 成岩作用研究部分将利用 从巴巴多斯运来的精确年代的铀-钍材料， 解释更新世微量金属记录的可行性 珊瑚化石