Relating experimental and geological rheology

Paterson, M. S.

doi:10.1007/s005310000158

Cited by 42 publications

(29 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The strength and deformation behavior of the continental and oceanic crust is generally assumed to depend on observation scale (Paterson, 2001). Localized heterogeneities like fault zones control the development of the brittle upper crust (Ben-Zion and Sammis, 2013;Faulkner et al, 2010), whereas high temperature shear zones impose constraints on the mechanical behavior of the lower ductile crust (Bürgmann and Dresen, 2008;Handy et al, 2007;Platt and Behr, 2011;.…”

Section: Introductionmentioning

confidence: 99%

Strain localization during high temperature creep of marble: The effect of inclusions

et al. 2014

View full text Add to dashboard Cite

The deformation of rocks in the Earth's middle and lower crust is often localized in ductile shear zones. To better understand the initiation and propagation of high-temperature shear zones induced by the presence of structural and material heterogeneities, we performed deformation experiments in the dislocation creep regime on Carrara marble samples containing weak (limestone) or strong (novaculite) second phase inclusions. The samples were mostly deformed in torsion at a bulk shear strain rate of ≈ 1.9x10 -4 s -1 to bulk shear strains γ between 0.02 and 2.9 using a Paterson-type gas deformation apparatus at 900°C temperature and 400 MPa confining pressure. At low strain, twisted specimens with weak inclusions show minor strain hardening that is replaced by strain weakening at γ > 0.1 -0.2.Peak shear stress at the imposed conditions is about 20 MPa, which is ≈8% lower than the strength of intact samples. Strain progressively localized within the matrix with increasing bulk strain, but decayed rapidly with increasing distance from the inclusion tip.Microstructural analysis shows twinning and recrystallization within this process zone, with a strong crystallographic preferred orientation, dominated by {r} and (c) slip in .Recrystallization-induced weakening starts at local shear strain of about 1 in the process zone, corresponding to a bulk shear strain of about 0.1. In contrast, torsion of a sample containing strong inclusions deformed at similar stress as inclusion-free samples but do not show localization. The experiments demonstrate that the presence of weak heterogeneities initiates localized creep at local stress concentrations around the inclusion tips. Recrystallizationinduced grain size reduction may only locally promote grain boundary diffusion creep. Accordingly, the bulk strength of the twisted aggregate is close to or slightly below the lower (isostress) strength bound, determined from the flow strength and volume fraction of matrix and inclusions.

show abstract

Section: Introductionmentioning

confidence: 99%

Strain localization during high temperature creep of marble: The effect of inclusions

et al. 2014

View full text Add to dashboard Cite

show abstract

“…The main limitation of such data is the problem of extrapolation to slow natural strain rate and from laboratory to larger scales (Paterson 1987(Paterson , 2001. In contrast, studies of microstructures in naturally deformed minerals can potentially provide information on the deformation mechanisms that actually operate in the Earth.…”

Section: Deformation Mechanisms and Rheology Of Crust And Upper Mantlmentioning

confidence: 99%

Current issues and new developments in deformation mechanisms, rheology and tectonics

Meer

Drury

Bresser

et al. 2002

View full text Add to dashboard Cite

Abstract:We present a selective overview of current issues and outstanding problems in the field of deformation mechanisms, rheology and tectonics. A large part of present-day research activities can be grouped into four broad themes. First, the effect of fluids on deformation is the subject of many field and laboratory studies. Fundamental aspects of grain boundary structure and the diffusive properties of fluid-filled grain contacts are currently being investigated, applying modern techniques of light photomicrography, electrical conductivity measurement and Fourier Transform Infrared (FTIR) microanalysis. Second, the interpretation of microstructures and textures is a topic of continuous attention. An improved understanding of the evolution of recrystallization microstructures, boundary misorientations and crystallographic preferred orientations has resulted from the systematic application of new, quantitative analysis and modelling techniques. Third, investigation of the theology of crust and mantle minerals remains an essential scientific goal. There is a focus on improving the accuracy of flow laws, in order to extrapolate these to nature. Aspects of strain and phase changes are now being taken into account. Fourth, crust and lithosphere tectonics form a subject of research focused on large-scale problems, where the use of analogue models has been particularly successful. However, there still exists a major lack of understanding regarding the microphysical basis of crust-and lithosphere-scale localization of deformation.

show abstract

“…The fastest strain rates with such processes (10 -10 s -1 , Gratier et al, 2009) are found within active creeping zones, such as along the San Andreas fault (Titus et al, 2006). Reproducing such low strain rates on natural minerals in the presence of a fluid in the laboratory is therefore a challenge (Paterson, 2001). Strain rates as low as 10 -11 s -1 may be registered in the lab (Gratier, 1993;Dysthe et al, 2003;Berest et al, 2004;Le Guen et al, 2007;Gratier et al, 2009), however the strain values are very low and not necessary representative of large finite deformation.…”

Section: Introductionmentioning

confidence: 99%

Fault Permeability and Strength Evolution Related to Fracturing and Healing Episodic Processes (Years to Millennia): the Role of Pressure Solution

Gratier

2011

Oil Gas Sci. Technol. – Rev. IFP Energies nouvelles

View full text Add to dashboard Cite

Résumé -Évolution de la perméabilité et de la résistance des failles associée à des processus épisodiques de fracturation et colmatage (années -millénaires) : le rôle de la dissolution cristallisation sous contrainte -Il est bien connu que les fluides circulent le long des failles, mais il est aussi démontré que les failles se comportent en barrières imperméables. Il faut donc considérer que les failles puissent être successivement des chemins ouverts et fermés. À l'échelle de temps des activités humaines (années à millénaires), l'étude du cycle sismique offre la possibilité de construire un modèle de telles évolutions. Selon ce modèle, la fracturation sismique (ou hydraulique) ouvre les chemins des fluides de manière quasi-instantanée le long des failles avec des processus d'amollissement et de fluage post-fracturation. La fermeture de ces chemins de fluide par cicatrisation de la faille est beaucoup plus progressive, associée à un durcissement et une reconstitution de pression des fluides. De tels comportements transitoires ont des conséquences majeures dans les études : -de l'évolution de la perméabilité le long des failles, avec application à l'exploitation de réservoirs pétroliers et aux stockages de fluides et de déchets ; -de l'évolution des flux de fluides le long des failles avec application au bilan des échanges et à l'évolution du climat à l'échelle de la terre ; -du temps de retour des séismes et de la probabilité de leur occurrence. Le but est de comprendre et d'évaluer la cinétique des processus et donc les temps caractéristiques spécifiques des cycles de fracturation et de colmatage. Des résultats d'expériences de laboratoire et d'étude de failles naturelles sont présentés qui montrent comment des processus de dissolution cristallisation sous contrainte peuvent expliquer à la fois les processus de fluage et de colmatage, et la façon dont ils sont associés dans la nature. Les divers processus de cicatrisation des failles sont discutés, avec leurs temps caractéristiques très variés de quelques semaines à des millénaires. On montre comment ils peuvent être intégrés dans des lois de fluage et de colmatage. Les expériences de laboratoire en donnent les valeurs de certains paramètres (cinétiques, thermodynamiques). D'autres paramètres de ces lois doivent cependant toujours être évalués à partir d'études de structures naturelles (géométrie des chemins de transfert, conditions de pression et température, nature des fluides et des minéraux). Ainsi, la durée des cycles de fracturation et colmatage est reliée, d'une certaine façon, au contexte géologique de la zone de faille. Finalement, comme ces processus d'évolution de perméabilité, de pression fluide et de résistance mécanique interagissent et se produisent à différentes échelles de temps et d'espace, ils doivent être intégrés dans des modèles numériques qui sont brièvement discutés.

show abstract

Relating experimental and geological rheology

Cited by 42 publications

References 55 publications

Strain localization during high temperature creep of marble: The effect of inclusions

Strain localization during high temperature creep of marble: The effect of inclusions

Current issues and new developments in deformation mechanisms, rheology and tectonics

Fault Permeability and Strength Evolution Related to Fracturing and Healing Episodic Processes (Years to Millennia): the Role of Pressure Solution

Contact Info

Product

Resources

About