DOI: 10.1029/2012GL054372
论文题名: First principles viscosity and derived models for MgO-SiO2 melt system at high temperature
作者: Karki B.B. ; Zhang J. ; Stixrude L.
刊名: Geophysical Research Letters
ISSN: 0094-9428
EISSN: 1944-9159
出版年: 2013
卷: 40, 期: 1 起始页码: 94
结束页码: 99
语种: 英语
Scopus关键词: Configurational entropy
; First principles
; First-principles molecular dynamics
; Frictional heating
; Nonlinear dependence
; Orders of magnitude
; Thermal evolution
; Viscosity-temperature
; Liquids
; Magnesia
; Molecular dynamics
; Silica
; Silicates
; Viscosity
; entropy
; high temperature
; magma
; melt
; molecular analysis
; nonlinearity
; slip rate
; thermal evolution
; thermal regime
; viscosity
英文摘要: The viscosity of silicate liquids at high temperature is crucial to our understanding of chemical and thermal evolution of the Earth since its early stages. First-principles molecular dynamics simulations of seven liquids across the MgO-SiO2 binary show that the viscosity varies by several orders of magnitudes with temperature and composition. Our results follow a compensation law: on heating, the viscosity of all compositions approaches a uniform value at 5000 K, above which pure silica becomes the least viscous liquid. Viscosity depends strongly on composition (fourth power), implying a strong nonlinear dependence of the configurational entropy on composition. Using the simulation results, we derive and evaluate different types (Arrhenius and non-Arrhenius) of models for accurate description of the viscosity-temperature- composition relationship. Our results span the thermal regime expected in a magma ocean, and indicate that melt migration is important for understanding the generation and preservation of melts from frictional heating at very fast slip in impact processes. © 2013. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84874819376&doi=10.1029%2f2012GL054372&partnerID=40&md5=67851a38cd66d65e4bdb41434d9f771a
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/6692
Appears in Collections: 气候减缓与适应
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作者单位: Computer Science and Engineering Division, Louisiana State University, Baton Rouge, LA 70803, United States
Recommended Citation:
Karki B.B.,Zhang J.,Stixrude L.. First principles viscosity and derived models for MgO-SiO2 melt system at high temperature[J]. Geophysical Research Letters,2013-01-01,40(1).