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DOI	10.1016/j.epsl.2020.116622
	The quartz α↔β phase transition: Does it drive damage and reaction in continental crust?
	Johnson S.E.; Song W.J.; Cook A.C.; Vel S.S.; Gerbi C.C.
发表日期	2021
ISSN	0012821X
卷号	553
英文摘要	The α↔β phase transition in quartz is accompanied by relatively large, anisotropic changes in cell volume and elastic stiffness properties. Because quartz is among the most abundant minerals in Earth's continental crust, these changes have the potential to profoundly influence the state of stress, mechanical properties, metamorphism, and rheology of crustal rocks. Laboratory experiments confirm strongly enhanced microcracking as rocks cross the transition. In addition, limited seismological studies suggest that the α↔β transition may cause extensive microcracking in the crust. However, the micromechanical basis for potential transition-induced damage has not been quantitatively explored. Here we use numerical methods to show that elastic stresses arising from the transition can greatly exceed the brittle tensile and shear strengths of common crustal rocks and minerals at various confining pressures. In particular, we show that contraction during the down-temperature β→α transition is far more effective than expansion during the up-temperature α→β transition at promoting possible brittle failure and/or recrystallization (damage). Our results suggest that the α↔β transition may play an important role in damaging the continental crust, particularly in rock volumes that experience geologically rapid changes in temperature or pressure. In these environments, the transition may weaken rocks, establish transient permeability, facilitate advective mass transport and metamorphic reactions, and potentially nucleate earthquakes. © 2020
关键词	mechanical damage microcracking-enhanced fluid flow microcracking-enhanced reaction quartz α↔β phase transition rheology volumetric strain
英文关键词	Microcracking; Numerical methods; Quartz; Brittle failures; Confining pressures; Continental crusts; Elastic stiffness; Laboratory experiments; Metamorphic reactions; Micro-mechanical; State of stress; Metamorphic rocks; continental crust; damage; elasticity; fluid flow; microcrack; phase transition; quartz; rheology; rock mechanics; shear strength; strain analysis; tensile strength
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203153
作者单位	School of Earth and Climate Sciences, University of Maine, Orono, ME 04469, United States; Department of Mechanical Engineering, University of Maine, Orono, ME 04469, United States
推荐引用方式 GB/T 7714	Johnson S.E.,Song W.J.,Cook A.C.,et al. The quartz α↔β phase transition: Does it drive damage and reaction in continental crust?[J],2021,553.
APA	Johnson S.E.,Song W.J.,Cook A.C.,Vel S.S.,&Gerbi C.C..(2021).The quartz α↔β phase transition: Does it drive damage and reaction in continental crust?.Earth and Planetary Science Letters,553.
MLA	Johnson S.E.,et al."The quartz α↔β phase transition: Does it drive damage and reaction in continental crust?".Earth and Planetary Science Letters 553(2021).