平衡气体和碳酸盐标准衍生的双 (Δ47和Δ48) 聚集同位素值
Jamie K Lucarelli1, Hannah M Carroll1, Robert N Ulrich1
1Department of Earth, Planetary, and Space Sciences, Department of Atmospheric and Oceanic Sciences, Center for Diverse Leadership in Science, Institute of the Environment and Sustainability, UCLA, Los Angeles, CA, USA.
Geochemistry, geophysics, geosystems : G(3)
|October 13, 2023
概括
碳酸盐凝聚同位素地质化学现在使用二氧化碳同位素 (Δ47和Δ48) 的配对分析来研究非平衡分离并改善地热学. 这项研究通过分析广泛的多年多仪器数据来完善温度估计.
科学领域:
- 地质化学 地质化学
- 同位素地球化学 同位素地球化学
- 古气候学 古气候学
背景情况:
- 碳酸盐凝聚同位素地质化学传统上使用m/z 47 CO2的质谱仪进行地热测量.
- 最近的研究表明,对m/z 47 (Δ47) 和m/z 48 (Δ48) 同位素的对分析为非平衡分数和精细的温度估计提供了洞察力.
研究的目的:
- 用广泛的多年多仪器数据限制碳酸盐样本和标准的Δ47和Δ48值.
- 研究Δ47-Δ48,Δ47温度和Δ48温度之间的平衡关系.
- 将结果与以前的发现进行比较,并从多个实验室计算平衡回归.
主要方法:
- 使用了5448个Δ47和3400个Δ48复制碳酸盐样品/标准的测量.
- 分析了 183 个 Δ47 和 195 个 Δ48 复制的气体标准测量 (2015-2021).
- 计算了酸消化分成因子 (ε47和 ε48) 以及它们对初始聚合同位素值的依赖.
主要成果:
- 27个样本的限制 Δ47 和 Δ48 值,包括魔鬼洞洞穴石灰岩.
- 对于 Δ47-Δ48, Δ47-温度和 Δ48-温度的关系建立了平衡回归.
- 报告的酸消化分成因子,以计算初始聚合同位素值.
结论:
- 对D47和D48同位素的对分析增强了碳酸结合同位素地质化学的应用.
- 该研究提供了精细的温度估计和对非平衡同位素分离的洞察.
- 精确地确定分化因子对于可靠的地热量测量至关重要.
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