of Geophysical Research : Solid Earth On the Mechanical Effects of Poroelastic Crystal Mush in Classical Magma Chamber Models
of Geophysical Research : Solid Earth On the Mechanical Effects of Poroelastic Crystal Mush in Classical Magma Chamber Models
复制标题
地球物理研究: 固体地球对经典岩浆房模型中多孔弹性晶体糊的机械效应
DOI：
--
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
and R B Jones
中科院分区：
文献类型：
--
作者：
Y. Liao;S. Soule;and R B Jones
改进对岩浆房力学行为的约束对于理解火山过程至关重要；然而，晶体糊状物在岩浆房力学演化中的作用尚未得到系统的研究。现有的岩浆房模型通常认为岩浆房是被弹性地壳包围的孤立熔融体。在这项研究中，我们建立了一个物理模型来解释岩浆房中晶体糊状物的存在和性质，并研究了它对注入新岩浆期间和之后的力学过程的影响。我们的模型假设岩浆房是一个球形体，由液态岩浆的液体核心组成，其外壳是晶体糊状的，主要表现为孔隙弹性物质。我们研究了岩浆房在注入过程中和注入后的随时间演化特征，发现在注入停止后，超压和拉应力等量仍在继续演化，这是弹性（无模）模型所不具备的特征。与注入后演化相关的时间尺度从几小时到几千年不等，这取决于浆糊的微观力学特性、岩浆的粘度和岩浆室的大小。我们将我们的孔隙弹性结果与具有有效粘弹性壳的岩浆房的行为进行了比较，发现只有孔隙弹性模型在任何固定的糊状体积分数下显示出与岩浆房大小的时间尺度依赖。研究表明，晶体糊状物对地壳岩浆储层的力学行为有显著影响。
Improved constraints on the mechanical behavior of magma chambers is essential for understanding volcanic processes; however, the role of crystal mush on the mechanical evolution of magma chambers has not yet been systematically studied. Existing magma chamber models typically consider magma chambers to be isolated melt bodies surrounded by elastic crust. In this study, we develop a physical model to account for the presence and properties of crystal mush in magma chambers and investigate its impact on the mechanical processes during and after injection of new magma. Our model assumes the magma chamber to be a spherical body consisting of a liquid core of fluid magma within a shell of crystal mush that behaves primarily as a poroelastic material. We investigate the characteristics of time-dependent evolution in the magma chamber, both during and after the injection, and find that quantities such as overpressure and tensile stress continue to evolve after the injection has stopped, a feature that is absent in elastic (mushless) models. The time scales relevant to the postinjection evolution vary from hours to thousands of years, depending on the micromechanical properties of the mush, the viscosity of magma, and chamber size. We compare our poroelastic results to the behavior of a magma chamber with an effectively viscoelastic shell and find that only the poroelastic model displays a time scale dependence on the size of the chamber for any fixed mush volume fraction. This study demonstrates that crystal mush can significantly influence the mechanical behaviors of crustal magmatic reservoirs.
DOI：
10.1144/sp422.11
发表时间：
2015-01-01
期刊：
CHEMICAL, PHYSICAL AND TEMPORAL EVOLUTION OF MAGMATIC SYSTEMS
影响因子：
--
作者：
Caricchi, Luca;Blundy, Jon
通讯作者：
Blundy, Jon