Thermal impact of magmatism in subduction zones
Thermal impact of magmatism in subduction zones
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DOI：
10.1016/j.epsl.2017.10.015
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发表时间：
2017-01
影响因子：
5.3
通讯作者：
D. Jones;R. Katz;Meng Tian;John Frederick Rudge
中科院分区：
文献类型：
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作者：
D. Jones;R. Katz;Meng Tian;John Frederick Rudge
俯冲带的岩浆活动形成了大陆地壳，并导致了地球上大部分的陆基火山活动。岩浆的生产速度和组成受俯冲带热构造的控制。最近，一系列地球化学和热流证据汇集在一起，表明弧下岩石圈深处的俯冲带比忽略岩浆作用的经典热力学模型所预测的要热。我们表明，这种差异可以通过考虑岩浆传递的热量来解决。在我们的一维和二维数值模型和标度分析中，感热和潜热的岩浆输送局部改变了典型模型的热结构约300 K，使预测的地表热流和岩石圈中部温度增加到观测值。我们发现感热平流大于潜热沉积。根据这些结果，我们认为岩浆迁移的热输运影响了弧火山的化学性质和位置。
Magmatism in subduction zones builds continental crust and causes most of Earth's subaerial volcanism. The production rate and composition of magmas are controlled by the thermal structure of subduction zones. A range of geochemical and heat flow evidence has recently converged to indicate that subduction zones are hotter at lithospheric depths beneath the arc than predicted by canonical thermomechanical models, which neglect magmatism. We show that this discrepancy can be resolved by consideration of the heat transported by magma. In our one- and two-dimensional numerical models and scaling analysis, magmatic transport of sensible and latent heat locally alters the thermal structure of canonical models by ∼300 K, increasing predicted surface heat flow and mid-lithospheric temperatures to observed values. We find the advection of sensible heat to be larger than the deposition of latent heat. Based on these results we conclude that thermal transport by magma migration affects the chemistry and the location of arc volcanoes.