Timescales of magma transport in the Columbia River flood basalts, determined by paleomagnetic data
Timescales of magma transport in the Columbia River flood basalts, determined by paleomagnetic data
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DOI：
10.1016/j.epsl.2021.117169
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发表时间：
2021-10-20
影响因子：
5.3
通讯作者：
Karlstrom, Leif
中科院分区：
文献类型：
--
作者：
Biasi, Joseph;Karlstrom, Leif
洪水玄武岩代表了地球历史上的重大事件，部分原因是它们与大的气候扰动和质量波动有关。然而，个别洪水玄武岩喷发，直接影响潜在的环境危机的持续时间，受到很大的限制。在这里，我们使用的古地磁数据和热模拟相结合，以创建一个磁地质温度计（MGT），可以限制岩浆导管和侵入体的主动运输寿命。我们应用MGT技术的八个馈线堤段的哥伦比亚河玄武岩（CRB），表明一些堤段积极加热主机岩石不到一个月，而其他部分可能已经活跃了几年。结果表明，喷发率，局部空间沿走向的堤段，高达1-8公里（3）天（-1）。这些结果有助于上下文对比CRB喷发持续时间的现场证据，并提出了一个途径，约束全球洪水玄武岩岩浆活动的速度，是超出了地质年代学的分辨率。(C)2021年，任作者。由爱思唯尔公司出版
Flood basalts represent major events in Earth History, in part because they are linked to large climate perturbations and mass extinctions. However, the durations of individual flood basalt eruptions, which directly impact potential environmental crises, are poorly constrained. Here we use a combination of paleomagnetic data and thermal modeling to create a magnetic geothermometer (MGT) that can constrain the active transport lifetime of magmatic conduits and intrusions. We apply the MGT technique to eight feeder dike segments of the Columbia River basalts (CRB), demonstrating that some dike segments were actively heating host rocks for less than one month, while other segments may have been active for several years. Results suggest that eruption rates, localized spatially along-strike of dike segments, were as high as 1-8 km(3)day(-1). These results help contextualize field evidence for contrasting CRB eruption durations and suggest a pathway for constraining the tempo of global flood basalt magmatism that is beyond the resolution of geochronology. (C) 2021 The Author(s). Published by Elsevier B.V.