DOI: 10.1016/j.epsl.2020.116622
论文题名: The quartz α↔β phase transition: Does it drive damage and reaction in continental crust?
作者: Johnson S.E. ; Song W.J. ; Cook A.C. ; Vel S.S. ; Gerbi C.C.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2021
卷: 553 语种: 英语
中文关键词: 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
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 Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165531
Appears in Collections: 气候变化与战略
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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
Recommended Citation:
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]. Earth and Planetary Science Letters,2021-01-01,553