Magmatic regions are typically viewed as vertical systems, with magma coming in the bottom and either freezing in the crust to form plutons or erupting to form volcanic rocks. Maintaining an upper‐crustal magmatic system for 10⁵–10⁶ Ma timescales requires establishing and maintaining a strong perturbation in the geotherm via continued input of magma from below. Thermal models indicate that establishing such a system requires the energy content of a vertical stack of magma tens of km thick, and maintaining the system requires continual supply of tens of km per million years. These rates of magma addition into the upper crust would require rapid crustal thickening and surface uplift, neither of which are observed at the required scale. Mass and energy balance issues are ameliorated if large magmatic systems are primarily lower‐crustal phenomena without long‐term upper‐crustal storage and if horizontal space‐making processes (extension), rather than vertical inflation, focus magmatism, and induce decompression melting.

中文翻译：

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磁动力系统寿命，深度和垂直范围的热约束

岩浆区域通常被视为垂直系统，岩浆进入底部，或者在地壳中冻结形成云母，或者喷发而形成火山岩。维持10 ⁵ –10 ⁶的上地壳岩浆系统 Ma时标要求通过不断从下方输入岩浆来建立和维持地热中的强烈扰动。热模型表明，建立这样一个系统需要垂直堆积的岩浆数十公里厚的能量，而维持该系统则需要持续供应每百万年几十公里的能量。这些岩浆添加到上地壳的速率将需要快速的地壳增厚和表面隆升，而在所需的规模上都没有观察到。如果大型岩浆系统主要是没有长期上地壳储存的下地壳现象，并且如果水平空间形成过程（扩展）而不是垂直膨胀，集中岩浆作用并引起减压融化，则质量和能量平衡问题将得到改善。