概括
马斯科克斯入侵中的同位素比率揭示了岩层之间脱的化学和同位素交换. 这种扩散性污染过程在数千年的时间里显著影响了岩腔中的酸盐液体.
科学领域:
- 地质化学 地质化学
- 伊格尼岩石学 伊格尼岩石学
- 同位素地球化学 同位素地球化学
背景情况:
- 层层的马菲克入侵提供了对岩室过程的洞察力.
- 了解岩混合和分化对于解释地质记录至关重要.
- 同位素特征 (和) 是岩演变的强有力的标志物.
研究的目的:
- 为了研究分离的同位素和散装化学交换在一个分层的岩系统.
- 为了建模地质和状液体接口之间的扩散交换的影响.
- 为了限制控制岩室演变的时间尺度和物理过程.
主要方法:
- 在Muskox入侵的累积物中分析了 (87) Sr/ (86) Sr和 (143) Nd/ (144) Nd的比率.
- 开发了一个数值模型,模拟分层液体层之间的扩散交换.
- 模型预测与观察到的同位素变异的比较.
主要成果:
- 观察到的 (87) Sr/ (86) Sr和 (143) Nd/ (144) Nd比率的变化表明汇率脱.
- 建模表明,扩散交换在10^3到10^4年内显著改变同位素组成.
- 该过程在具有明显液体接口的多层岩室中特别有效.
结论:
- 扩散污染是影响岩系统中同位素特征的关键过程.
- 这种机制有助于解释分层侵入中的同位素异质性.
- 该研究为使用扩散污染来限制岩室动态和时间尺度提供了一个框架.
相关概念视频
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Inductively coupled plasma–mass spectrometry (ICP–MS) is a highly selective and sensitive technique for accurate elemental analysis. Though the analysis of ICP–MS mass spectra is comparatively straightforward, it is affected by spectroscopic and non-spectroscopic interferences. Spectroscopic interferences arise when the plasma contains ionic species with an m/z value the same as the analyte ion. Spectroscopic interference can be categorized as isobaric, polyatomic ions, and refractory oxide ion...
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For instance, group IV...
For instance, group IV...
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Magnetic Susceptibility and Permeability
In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
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