The effect of dislocation density on the aqueous solubility of quartz and some geologic implications: A theoretical approach

Wintsch, Robert P.; Dunning, Jeremy

doi:10.1029/jb090ib05p03649

Cited by 106 publications

(36 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover the alteration of feldspars leading to its breakdown, growth of muscovite and the loss of K into fluid was shown to be significantly important in mylonites (Knipe and Wintsch 1985). The grains of quartz and K-feldspar might be dissolved preferentially because of its high dislocation density that may increase their solubility (Wintsch and Dunning 1985).…”

Section: Discussionmentioning

confidence: 99%

Pressure solution in rocks: focused ion beam/transmission electron microscopy study on orthogneiss from South Armorican Shear Zone, France

Bukovská

Wirth

Morales

2015

Contrib Mineral Petrol

View full text Add to dashboard Cite

In order to characterize the µm-to-nm structures related to operation of pressure solution on phase boundaries in naturally deformed rocks, we have performed a detailed focused ion beam/transmission electron microscopy study in ultramylonite samples from South Armorican Shear Zone (France) that focused on grain boundary scale. We have studied phase boundaries between quartz, K-feldspar and white mica both in 2 and 3D and compare our evidences with theoretical dissolution-precipitation models in the current literature. The dissolution (re)precipitation processes lead to the development of different features at different phase boundaries. In both quartz-white mica and quartz-K-feldspar phase boundaries, voids were ubiquitously observed. These voids have different shapes and the development of some of them is crystallographically controlled. In addition, part of these voids might be filled with vermiculite.Amorphous leached layers with kaolinite composition were observed at the boundaries of Kfeldspar-quartz and K-feldspar-white mica. The development of different features along the phase boundaries is mainly controlled by the crystallography of the phases sharing a common interface, together with the presence of fluids that either leaches or directly dissolve the mineral phases. In addition, the local dislocation density in quartz may play an important role during pressure solution.We suggest that the nano-scale observations of the quartz -white mica phase boundaries show direct evidence for operation of island-and-channel model as described in Wassmann and Stöckhert (2013), while K-feldspar -quartz phase boundaries represents amorphous layers formed via interface-coupled dissolution-reprecipitation as described by Hellmann et al. (2012).

show abstract

Section: Discussionmentioning

confidence: 99%

Pressure solution in rocks: focused ion beam/transmission electron microscopy study on orthogneiss from South Armorican Shear Zone, France

Bukovská

Wirth

Morales

2015

Contrib Mineral Petrol

View full text Add to dashboard Cite

show abstract

“…Hippertt (1994) suggested that the initial porosity is loosely connected to the preferential dissolution of quartz at sites where dislocation tangles intersect grain boundaries (cf. Wintsch and Dunning, 1985). In both the sample of this study and of Hippertt (1994), there is a clear link between the pore orientation and the bulk finite strain.…”

Section: Nucleation Of Creep Cavities During Gsi Creepmentioning

confidence: 99%

Hierarchical creep cavity formation in an ultramylonite and implications for phase mixing

et al. 2017

View full text Add to dashboard Cite

Abstract. Establishing models for the formation of wellmixed polyphase domains in ultramylonites is difficult because the effects of large strains and thermo-hydro-chemomechanical feedbacks can obscure the transient phenomena that may be responsible for domain production. We use scanning electron microscopy and nanotomography to offer critical insights into how the microstructure of a highly deformed quartzo-feldspathic ultramylonite evolved. The dispersal of monomineralic quartz domains in the ultramylonite is interpreted to be the result of the emergence of synkinematic pores, called creep cavities. The cavities can be considered the product of two distinct mechanisms that formed hierarchically: Zener-Stroh cracking and viscous grain-boundary sliding. In initially thick and coherent quartz ribbons deforming by grain-size-insensitive creep, cavities were generated by the Zener-Stroh mechanism on grain boundaries aligned with the Y Z plane of finite strain. The opening of creep cavities promoted the ingress of fluids to sites of low stress. The local addition of a fluid lowered the adhesion and cohesion of grain boundaries and promoted viscous grain-boundary sliding. With the increased contribution of viscous grainboundary sliding, a second population of cavities formed to accommodate strain incompatibilities. Ultimately, the emergence of creep cavities is interpreted to be responsible for the transition of quartz domains from a grain-size-insensitive to a grain-size-sensitive rheology.

show abstract

“…Fig. 28b portrays the most important contribution in pressure solution, the work W performed by the surroundings on a solid grain when a volume ΔV is moved from face 1 to face 2: and 300 MPa (Wintsch and Dunning, 1985). The range of minimum and maximum values is given.…”

Section: Driving Force Of Pressure Solutionmentioning

confidence: 99%

“…For a large enough density of dislocations, for example greater than 10 10 dislocations per cm 2 for quartz, the free energy of a crystal can be significantly increased (Table 1). The energy of a dislocation can be divided in two terms: the energy of the core of the dislocation itself, and the strain energy due to the deformation of the crystalline lattice (Wintsch and Dunning, 1985).…”

Section: Chemical Potential Of Solids In Contact With Their Solutionmentioning

confidence: 99%

The Role of Pressure Solution Creep in the Ductility of the Earth’s Upper Crust

Gratier

Dysthe

Renard

2013

Advances in Geophysics

241

274

View full text Add to dashboard Cite

The aim of this review is to characterize the role of pressure solution creep in the ductility of the Earth's upper crust and to describe how this creep mechanism competes and interacts with other deformation mechanisms. Pressure solution creep is a major mechanism of ductile deformation of the upper crust, accommodating basin compaction, folding, shear zone development, and fault creep and interseismic healing. However, its kinetics is strongly dependent on the composition of the rocks (mainly the presence of phyllosilicates minerals that activate pressure solution) and on its interaction with fracturing and healing processes (that activate and slow down pressure solution, respectively).The present review combines three approaches: natural observations, theoretical developments, and laboratory experiments. Natural observations can be used to identify the pressure solution markers necessary to evaluate creep law parameters, such as the nature of the material, the temperature and stress conditions or the geometry of mass transfer domains. Theoretical developments help to investigate the thermodynamics and kinetics of the processes and to build theoretical creep laws.Laboratory experiments are implemented in order to test the models and to measure creep law parameters such as driving forces and kinetic coefficients. Finally, applications are discussed for the modelling of sedimentary basin compaction and fault creep. The sensitivity of the models to time is given particular attention: viscous versus plastic rheology during sediment compaction; steady state versus non-steady state behaviour of fault and shear zones. The conclusions discuss recent advances for modelling pressure solution creep and the main questions that remain to be solved. -IntroductionIn order to investigate the role of pressure solution creep in the ductility of the Earth's upper crust the various mechanical behaviour patterns of the upper crust must first be discussed. Two types of approach can be considered on this topic.1 -The mechanical behaviour of the upper crust is modelled using brittle theories, that include friction laws (Byerlee, 1978;Marone, 1998). This modelling approach is supported by two kinds of observations: (i) the maximum frequency of earthquakes is located within the first 15-20 km of the upper crust (Chen and Molnar, 1983;Sibson, 1982); (ii) laboratory experiments run at relatively fast strain-rates (faster than 10 -7 s -1 ) indicate a transition from frictional to plastic deformation at pressure and temperature conditions appropriate for a depth of 10-20 km (Kohlstedt et al., 1995;Paterson, 1978;Poirier, 1985).2 -Conversely, the behaviour of the upper crust is also modelled by ductile behaviour with creep laws (Wheeler, 1992). This modelling approach is supported by two kinds of observations: (i) geological structures exhumed from depth, such as compacted basin, folds and shear zones, and regional cleavage, indicate ductile behaviour throughout the upper crust (Argand, 1924;Hauck et al., 1998;Schmidt et al., 1996) (Fig. ...

show abstract

The effect of dislocation density on the aqueous solubility of quartz and some geologic implications: A theoretical approach

Abstract: The internal energy associated with dislocations is calculated in quartz as a function of dislocation density. These calculawhich would drive the diffusive mass transfer of SiO 2 out of the fault zone.

Cited by 106 publications

References 43 publications

Pressure solution in rocks: focused ion beam/transmission electron microscopy study on orthogneiss from South Armorican Shear Zone, France

Pressure solution in rocks: focused ion beam/transmission electron microscopy study on orthogneiss from South Armorican Shear Zone, France

Hierarchical creep cavity formation in an ultramylonite and implications for phase mixing

The Role of Pressure Solution Creep in the Ductility of the Earth’s Upper Crust

Contact Info

Product

Resources

About