Thermo‐poro‐mechanics of chemically active creeping faults. 1: Theory and steady state considerations

Alevizos, Sotiris; Poulet, Thomas; Veveakis, Manolis

doi:10.1002/2013jb010070

Cited by 53 publications

(54 citation statements)

References 88 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results from these methods are identical to the ones presented in [8,9], and we calibrated the required mesh size through a sensitivity analysis shown in Figure 3, opting for 30 mesh points to balance numerical accuracy and computational cost.…”

Section: Methodsmentioning

confidence: 99%

“…In our previous works, [8][9][10], we have highlighted the importance of the ratio of the Grunfest number, Gr, over the Damköhler number, Da.…”

Section: Gruntfest and Damköhler Numbersmentioning

confidence: 98%

“…In the present work, we follow a Continuum Mechanics approach that was previously presented in [8,11] for modelling a fault in creeping flow conditions, including multiphysics processes explained below. Therefore, we assume that all the deformation occurs in an infinite shear zone of thickness d (Figure 1).…”

Section: Problem Formulation-previous Workmentioning

confidence: 99%

“…Note that the effects of thermal pressurisation as well as that of the convective terms are neglected following the analysis in [8]. Here, we extend our previous consideration and adopt the visco-plastic flow law of [13,14] for the material, where the effect of high pore-pressure and temperature is taken into account:˙…”

Section: Problem Formulation-previous Workmentioning

confidence: 99%

“…In this work, we study the dynamics of a highly non-linear system of reaction-diffusion partial differential equations, which was shown to adequately approximate the physical processes occurring in seismogenic thrust faults [8][9][10]. The system of equations describes the evolution of temperature and excess pore fluid pressure in a fault prone to chemical reactions under mechanical loading.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Analysis of Dynamics in Multiphysics Modelling of Active Faults

et al. 2016

View full text Add to dashboard Cite

Instabilities in Geomechanics appear on multiple scales involving multiple physical processes. They appear often as planar features of localised deformation (faults), which can be relatively stable creep or display rich dynamics, sometimes culminating in earthquakes. To study those features, we propose a fundamental physics-based approach that overcomes the current limitations of statistical rule-based methods and allows a physical understanding of the nucleation and temporal evolution of such faults. In particular, we formulate the coupling between temperature and pressure evolution in the faults through their multiphysics energetic process(es). We analyse their multiple steady states using numerical continuation methods and characterise their transient dynamics by studying the time-dependent problem near the critical Hopf points. We find that the global system can be characterised by a homoclinic bifurcation that depends on the two main dimensionless groups of the underlying physical system. The Gruntfest number determines the onset of the localisation phenomenon, while the dynamics are mainly controlled by the Lewis number, which is the ratio of energy diffusion over mass diffusion. Here, we show that the Lewis number is the critical parameter for dynamics of the system as it controls the time evolution of the system for a given energy supply (Gruntfest number).

show abstract

Section: Methodsmentioning

confidence: 99%

“…In our previous works, [8][9][10], we have highlighted the importance of the ratio of the Grunfest number, Gr, over the Damköhler number, Da.…”

Section: Gruntfest and Damköhler Numbersmentioning

confidence: 98%

Section: Problem Formulation-previous Workmentioning

confidence: 99%

Section: Problem Formulation-previous Workmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Analysis of Dynamics in Multiphysics Modelling of Active Faults

et al. 2016

View full text Add to dashboard Cite

show abstract

Thermo‐poro‐mechanics of chemically active creeping faults: 2. Transient considerations

2014

Self Cite

View full text Add to dashboard Cite

This work studies the transient behavior of a chemically active, fluid‐saturated fault zone under shear. These fault zones are displaying a plethora of responses spanning from ultrafast instabilities, like thermal pressurization, to extremely slow creep localization events on geological timescales. These instabilities can be described by a single model of a rate‐dependent and thermally dependent fault, prone to fluid release reactions at critical temperatures which was introduced in our companion work. In this study we integrate it in time to provide regimes of stable creep, nonperiodic and periodic seismic slip events due to chemical pressurization, depending on the physical properties of the fault material. It is shown that this chemically induced seismic slip takes place in an extremely localized band, several orders of magnitude narrower than the initial shear zone, which is indeed the signature field observation. Furthermore, in the field and in laboratory experiments the ultralocalized deformation is embedded in a chemical process zone that forms part of the shear zone. The width of this zone is shown here to depend on the net activation energy of the chemical reaction. The larger the difference in forward and backward activation energies, the narrower is the chemical process zone. We apply the novel findings to invert the physical parameters from a 16year GPS observation of the Cascadia episodic tremor and slip events and show that this sequence is the fundamental mode of a serpentinite oscillator defined by slow strain localization accompanying shear heating and chemical dehydration reaction at the critical point, followed by diffusion and backward reaction leading the system back to slow slip.

show abstract

Modeling episodic fluid‐release events in the ductile carbonates of the Glarus thrust

Poulet

Veveakis

Herwegh

et al. 2014

Geophysical Research Letters

View full text Add to dashboard Cite

The exposed Glarus thrust displays midcrustal deformation with tens of kilometers of displacement on an ultrathin layer, the principal slip zone (PSZ). Geological observations indicate that this structure resulted from repeated stick-slip events in the presence of highly overpressured fluids. Here we show that the major characteristics of the Glarus thrust movement (localization, periodicity, and evidence of pressurized fluids) can be reconciled by the coupling of two processes, namely, shear heating and fluid release by carbonate decomposition. During this coupling, slow ductile creep deformation raises the temperature through shear heating and ultimately activates the chemical decomposition of carbonates. The subsequent release of highly overpressurized fluids forms and lubricates the PSZ, allowing a ductile fault to move tens of kilometers on millimeter-thick bands in episodic stick-slip events. This model identifies carbonate decomposition as a key process for motion on the Glarus thrust and explains the source of overpressured fluids accessing the PSZ.

show abstract

Thermo‐poro‐mechanics of chemically active creeping faults. 1: Theory and steady state considerations

Cited by 53 publications

References 88 publications

Analysis of Dynamics in Multiphysics Modelling of Active Faults

Analysis of Dynamics in Multiphysics Modelling of Active Faults

Thermo‐poro‐mechanics of chemically active creeping faults: 2. Transient considerations

Modeling episodic fluid‐release events in the ductile carbonates of the Glarus thrust

Contact Info

Product

Resources

About