在沉积岩中确定K同位素组成及其对区分沉积物起源的影响
Meng-Meng Cui1,2, Frédéric Moynier2, Ben-Xun Su1,3
1State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China.
Rapid communications in mass spectrometry : RCM
|February 26, 2025
概括
新的高精度质谱学揭示了沉积物中明显的 (K) 同位素变化. 这一进步为区分生物原和非生物原沉积物起源提供了一个新的工具.
科学领域:
- 地质化学 地质化学
- 分析化学 分析化学
- 环境科学 环境科学
背景情况:
- (K) 同位素分析对于理解地质过程至关重要.
- 较旧的质谱技术限制了K同位素组成测量的精度.
- 为了获得更高精度的K同位素数据,需要在仪器仪表方面取得进展.
研究的目的:
- 报告八种沉积物参考材料的K同位素组成,使用新一代的碰撞细胞多采集器感应合等离子体质谱仪 (CC-MC-ICP-MS).
- 评估K同位素作为沉积物生成的标记物的潜力.
- 为质量控制和实验室间比较提供高精度的K同位素数据.
主要方法:
- 使用努蓝宝石CC-MC-ICP-MS仪器进行高精度的K同位素分析.
- 在海洋,河口,河流沉积物和石灰岩参考材料中测量K同位素组成 (δ41K).
- 编制并分析了K度 (K2O重量%) 与同位素数据一起.
主要成果:
- 确定了八种参考材料的K同位素组成 (δ41K),显示了0.2‰.
- 生物沉积物表现出低度的K和广泛的K同位素变化 (δ41K:-1.88到0.94‰).
- 亚生性沉积物显示较轻的K同位素 (平均δ41K: -0.47‰) 和较高的K度.
结论:
- 努蓝宝石CC-MC-ICP-MS能够比上一代更准确地进行K同位素测量.
- 在K同位素的变化,特别是δ41K,可以有效地区分生态和非生态沉积物.
- 生成的高精度K同位素数据作为未来研究和质量保证的宝贵参考.
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