DOI: 10.1016/j.epsl.2018.05.005
Scopus记录号: 2-s2.0-85048521734
论文题名: Reaction fronts, permeability and fluid pressure development during dehydration reactions
作者: Leclère H. ; Faulkner D. ; Llana-Fúnez S. ; Bedford J. ; Wheeler J.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 496 起始页码: 227
结束页码: 237
语种: 英语
英文关键词: compaction
; gypsum dehydration
; permeability
; pore-fluid pressure
; reaction front
; subduction zone
Scopus关键词: Compaction
; Gypsum
; Mechanical permeability
; Porosity
; Reaction rates
; Earthquake triggering
; Hydrostatic conditions
; Low effective pressures
; Low porosity and permeability
; Pore fluid pressure
; Quantitative modeling
; Reaction front
; Subduction zones
; Dehydration
; bassanite
; compaction
; creep
; dehydration
; earthquake trigger
; fluid pressure
; gypsum
; metasomatism
; permeability
; pore pressure
; porosity
; prograde metamorphism
; reaction rate
; subduction zone
英文摘要: Fluids released by prograde metamorphism are often invoked to explain a range of crustal processes from earthquake triggering to metasomatism. These fluids can be either trapped and overpressured or released and channelized depending on the interplay between permeability, reaction rate and compaction. Experimental data are presented, measuring permeability, porosity and microstructural evolution throughout the dehydration of gypsum to form bassanite. Reaction fronts, regions over which the reaction largely occurs, are used as a framework to explain the results. Experiments were conducted under hydrostatic conditions at a constant temperature of 115 °C at two effective pressures of 60 MPa and 110 MPa and three pore-fluid pressures of 20, 40 and 60 MPa. At high effective pressure, creep of the gypsum solid framework results in low porosity and permeability, producing high pore-fluid pressure build-up that slows the reaction rate. A clearly defined narrow reaction front migrates along the sample and the average permeability remains low until the front sweeps across the entire sample. Conversely, at low effective pressure the reaction front is wide producing a permeable, drained network. Average permeability is enhanced significantly after only a small fraction of the reaction has completed, by the interconnection of open pores. This study shows that the width of reaction fronts and hence the permeability development is strongly controlled by compaction. The reaction front velocity is broadly dependent on permeability and the reaction driving force. A simple quantitative model for these relationships is developed. © 2018 The Author(s) Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109805
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 of Earth and Ocean Sciences, University of Liverpool, 4 Brownlow Street, Liverpool, L69 3GP, United Kingdom; Departamento de Geología, Universidad de Oviedo, calle Arias de Velasco s/n, Oviedo, 33005, Spain
Recommended Citation:
Leclère H.,Faulkner D.,Llana-Fúnez S.,et al. Reaction fronts, permeability and fluid pressure development during dehydration reactions[J]. Earth and Planetary Science Letters,2018-01-01,496