Nature Communications ( IF 14.7 ) Pub Date : 2023-07-17 , DOI: 10.1038/s41467-023-39912-5
Andreas Audétat 1 , Axel K Schmitt 2, 3 , Raphael Njul 1 , Megan Saalfeld 4 , Anastassia Borisova 5 , Yongjun Lu 6, 7
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Titanium diffusion profiles in quartz crystals are widely applied to constrain the duration of magmatic processes. However, experimentally determined Ti diffusion coefficients in quartz diverge by three orders of magnitude. To rectify this problem we derive Ti diffusion coefficients from natural quartz phenocrysts from the 1991 eruption at Mt. Pinatubo, by combining U-Th ages of small (15–40 µm long) zircon inclusions with Ti diffusion profiles measured at nearby growth zone contacts in the same quartz crystals. Application of the obtained data to quartz crystals with Ti-rich rims from thirteen silicic volcanic tuffs worldwide suggests that the magmas erupted years to thousands of years after magma chamber rejuvenation, with the priming time increasing with magma volume and decreasing temperature. Here we show that the time scales involved in the generation of silicic volcanic eruptions are much longer than originally thought.
中文翻译:
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钛在石英中扩散和硅质火山喷发的新限制
石英晶体中的钛扩散分布被广泛应用于限制岩浆过程的持续时间。然而,实验确定的石英中钛扩散系数相差三个数量级。为了纠正这个问题,我们通过将小型(15-40 µm 长)锆石包裹体的 U-Th 年龄与在附近生长区接触处测量的 Ti 扩散剖面相结合,从 1991 年皮纳图博山喷发的天然石英斑晶中推导出 Ti 扩散系数。相同的石英晶体。将获得的数据应用于来自世界各地十三个硅质火山凝灰岩的富钛边缘石英晶体表明,岩浆在岩浆室更新后数年至数千年才喷发,引发时间随着岩浆体积和温度的降低而增加。在这里,我们表明硅质火山喷发产生的时间尺度比最初想象的要长得多。