Analytical development of the use of the isotopic composition of gypsum hydration water as a paleoclimate tool

石膏水合水同位素组成作为古气候工具的分析开发

• 批准号: NE/I016716/1
• 负责人: David Hodell
• 金额: $ 5.33万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FI016716%2F1
• 关键词: Analytical; development; use; isotopic; composition

One of the fundamental problems in oxygen isotope paleoclimatology is the temperature equation is often under constrained. The d18O of calcite or aragonite can be measured on fossil shell material but a unique temperature solution is not possible without knowing the d18Owater from which the carbonate precipitated. ToC = 16 - 4.14 (d18Ocalcite - d18Owater) + 0.13 (d18Ocalcite - d18Owater)2 Or for aragonite: ToC = 21.8 - 4.69 (d18Oaragonite - d18Owater) Gypsum (CaSO4 2H2O) is a hydrated mineral that contains 20.9% crystallization water by weight. The 18O/16O and D/H of the hydration water record the isotopic ratio of the mother water from which the gypsum crystallized. Provided the fractionation factors are known and no isotopic exchange has occurred post-crystallization, the d18O of gypsum hydration water can be used to calculate the d18O of the water. Thus, tandem d18O measurements of both carbonate and gypsum hydration water from the same samples potentially offers a power paleoclimate tool for determining past temperature. We propose to measure the d18O and dD of gypsum hydration water (CaSO4 2H2O) in controlled experiments and natural samples to test the potential of this method and its applicability as a paleoclimate tool. Specifically we will: 1. Determine the isotopic fractionation factors between gypsum hydration water and mother water to high precision; 2. Experimentally evaluate the potential for post-crystallization isotope exchange of gypsum hydration water and ambient environmental water; 3. Test the application of tandem measurements of d18O of calcite and gypsum hydration water to reconstruct glacial tropical temperature using sediment cores from Lake Peten-Itza, Guatemala. Successful demonstration of the method by this pilot study would constitute a breakthrough for terrestrial paleothermometry studies and offer the opportunity for widespread application.

氧同位素古气候学的基本问题之一是温度方程通常受到约束。有方解石或aragonite的D18O可以在化石壳材料上测量，但是如果不知道碳酸盐沉淀的D18OWATER，则无法使用独特的温度溶液。 TOC = 16-4.14（D18OCALCITE -D18OWATER） + 0.13（D18ocalcite -D18OWATER）2或对于aragonite：TOC = 21.8-4.69（D18oaragonite -d18oaragonite -d18owater -d18owater）石膏（caso4 2H2O）是含有水文的矿物质，含有20.9％的水均浮雕。水合水的18o/16o和d/h记录了石膏结晶的母水的同位素比。如果分馏因子是已知的，并且在结晶后未发生同位素交换，则可以使用石膏水合水的D18O来计算水的D18O。因此，来自同一样品的碳酸盐和石膏水合水的串联D18O测量可能提供了一种功率古气候工具，用于确定过去的温度。我们建议在受控实验和天然样品中测量石膏水合水（Caso4 2H2O）的D18O和DD，以测试该方法的潜力及其作为古气候工具的适用性。具体而言，我们将：1。确定石膏水合水和母水之间的同位素分馏因子； 2。实验评估石膏水合水和环境环境水的结晶后同位素交换的潜力； 3。测试使用来自危地马拉的彼得·伊萨（Peten-Itza）湖的沉积物核心，对方解石和石膏水合水的D18O进行串联测量，以重建热带温度。这项试验研究成功证明该方法将构成陆地上的西部标准学研究的突破，并为广泛应用提供了机会。

项目成果

The influence of abrupt climate change on the ice-age vegetation of the Central American lowlands

• DOI: 10.1111/j.1365-2699.2011.02618.x
• 发表时间: 2012-03-01
• 期刊: JOURNAL OF BIOGEOGRAPHY
• 影响因子: 3.9
• 作者: Correa-Metrio, Alexander;Bush, Mark B.;Guilderson, Tom
• 通讯作者: Guilderson, Tom

Isotopic analysis of sulfur cycling and gypsum vein formation in a natural CO2 reservoir

天然 CO2 储层中硫循环和石膏脉形成的同位素分析

• DOI: 10.1016/j.chemgeo.2016.04.015
• 发表时间: 2016
• 期刊: Chemical Geology
• 影响因子: 3.9
• 作者: Chen F

Triple oxygen and hydrogen isotopes of gypsum hydration water for quantitative paleo-humidity reconstruction

• DOI: 10.1016/j.epsl.2017.10.020
• 发表时间: 2018-01-01
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Gazquez, Fernando;Morellon, Mario;Hodell, David A.
• 通讯作者: Hodell, David A.

Precise and accurate isotope fractionation factors (a$^{17}$O, a$^{18}$O and aD) for water and CaSO$_{4}$·2H$_{2}$O (gypsum)

水和 CaSO$_{4}$·2H$_{2}$O（石膏）的精确同位素分馏因子（a$^{17}$O、a$^{18}$O 和 aD）

• DOI: 10.17863/cam.8087
• 发表时间: 2017
• 作者: Gázquez F

Quantification of paleo-aquifer changes using clumped isotopes in subaqueous carbonate speleothems

• DOI: 10.1016/j.chemgeo.2018.05.046
• 发表时间: 2018-08-20
• 期刊: CHEMICAL GEOLOGY
• 影响因子: 3.9
• 作者: Gazquez, Fernando;Columbu, Andrea;Hodell, David A.
• 通讯作者: Hodell, David A.