DOI: 10.1016/j.epsl.2018.01.023
Scopus记录号: 2-s2.0-85042907787
论文题名: The effect of oxygen fugacity on the rheological evolution of crystallizing basaltic melts
作者: Kolzenburg S. ; Di Genova D. ; Giordano D. ; Hess K.U. ; Dingwell D.B.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 487 起始页码: 21
结束页码: 32
语种: 英语
英文关键词: crystallization
; disequilibrium processes
; lava
; magma
; oxygen fugacity
; rheology
Scopus关键词: Cooling
; Crystallization
; Deformation
; Earth (planet)
; Elasticity
; Oxygen
; Rheology
; Silicates
; Structural geology
; Thermodynamics
; Viscosity
; Viscosity measurement
; Crystallization rates
; lava
; Lava flow emplacements
; magma
; Oxygen fugacity
; Rheological characterization
; Rheological evolution
; Thermodynamics and kinetics
; Crystallization kinetics
; basalt
; crystallization
; disequilibrium
; emplacement
; fugacity
; lava flow
; oxygen
; rheology
; silicate melt
英文摘要: Storage and transport of silicate melts in the Earth's crust and their emplacement on the planet's surface occur almost exclusively at sub-liquidus temperatures. At these conditions, the melts undergo crystallization under a wide range of cooling-rates, deformation-rates, and oxygen fugacities (fO2). Oxygen fugacity is known to influence the thermodynamics and kinetics of crystallization in magmas and lavas. Yet, its influence on sub-liquidus rheology remains largely uncharted. We present the first rheological characterization of crystallizing lavas along natural cooling paths and deformation-rates and at varying fO2. Specifically, we report on apparent viscosity measurements for two crystallizing magmatic suspensions 1) at logfO2 of −9.15 (quartz–fayalite–magnetite buffer, QFM, −2.1) and 2) in air. These fugacities span a range of reduced to oxidized conditions pertinent to magma migration and lava emplacement. We find that: 1) crystallization at constant cooling-rates results in a quasi-exponential increase in the apparent viscosity of the magmatic suspensions until they achieve their rheological cut off temperature (Tcutoff), where the melt effectively solidifies 2) the rheological departure and Tcutoff increase with increasing fO2 and 3) increasing fO2 results in decreased crystallization-rates. Based on the experimental results and by comparison with previous rheological isothermal studies we propose a generalisation of the effect of fO2 on the dynamic rheological evolution of natural magmatic and volcanic suspensions. We further discuss the implications for magmatic transport in plumbing and storage systems (e.g. conduits, dikes and magma chambers) and during lava flow emplacement. © 2018 The Authors Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/110012
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Department für Geo- und Umweltwissenschaften, Ludwig-Maximilians-Universität, München, 80333, Germany; School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, United Kingdom; Dipartimento di Scienze della Terra, Università degli Studi di Torino, Torino, 10125, Italy
Recommended Citation:
Kolzenburg S.,Di Genova D.,Giordano D.,et al. The effect of oxygen fugacity on the rheological evolution of crystallizing basaltic melts[J]. Earth and Planetary Science Letters,2018-01-01,487