Determining cooling rates from mica 40 Ar/ 39 Ar thermochronology data: Effect of cooling path shape
Determining cooling rates from mica 40 Ar/ 39 Ar thermochronology data: Effect of cooling path shape
复制标题
根据云母 40 Ar/ 39 Ar 热年代学数据确定冷却速率：冷却路径形状的影响
DOI：
10.1111/ter.12390
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发表时间：
2019
期刊：
影响因子：
2.4
通讯作者：
McDonald C
中科院分区：
文献类型：
--
作者：
McDonald C
构造模型通常由来自扩散损失热年代学数据的变质冷却速率支持。这种冷却年龄通常通过Dodson的闭合温度（TC）公式与温度联系起来，该公式指定了1/时间形状的冷却路径（Contributions to Mineralogy and Petrology，1973，40，259）。然而，地质学家通常将冷却速率作为线性温度/时间形状进行讨论。我们提出了一系列简单的有限差分扩散模型在白云母和黑云母中的Ar扩散的结果，表明1/t和线性冷却路径之间记录的年龄差异显着增加与较热的起始温度，较慢的冷却速率和较小的晶粒尺寸。我们的研究结果表明，它是必不可少的，以约束的冷却路径的形状，以使测量数据的有意义的解释。
Tectonic models are commonly underpinned by metamorphic cooling rates derived from diffusive‐loss thermochronology data. Such cooling ages are usually linked to temperature via Dodson's closure temperature (TC) formulation, which specifies a 1/time‐shaped cooling path (Contributions to Mineralogy and Petrology, 1973, 40, 259). Geologists, however, commonly discuss cooling rates as a linear temperature/time shape. We present the results of a series of simple finite‐difference diffusion models for Ar diffusion in muscovite and biotite that show that the difference in recorded age between 1/t and linear cooling paths increases significantly with hotter starting temperatures, slower cooling rates and smaller grain sizes. Our results show that it is essential to constrain the cooling path shape in order to make meaningful interpretations of the measured data.