Viscous heating in silicate melts: An experimental and numerical comparison

Cordonnier, B.; Schmalholz, Stefan M.; Hess, Kai‐Uwe; Dingwell, Donald B.

doi:10.1029/2010jb007982

Cited by 44 publications

(38 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This lends power to the scaling provided by the dimensionless Deborah number and implies that we need only to define the liquid viscosity and a characteristic rate of deformation in order to predict whether a system will flow viscously or rupture violently. For example, the working viscosity of the analogue fluid used in Kameda and Kuribara (2008) is 10 0 l 10 10 Pa.s, which extends to much lower used in Cordonnier et al (2012b), and yet the scaling with the Deborah number holds across a broad range simply because the deformation timescale was also smaller in the former example.…”

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 97%

“…3, we plot those with a measureable temperature increase as filled symbols and those without this feature as unfilled symbols. To explain this, we plot the threshold dimensionless Brinkman number of unity Br ¼ 1, using an estimation of the loss power density for the furnace and sample size used U l ¼ 10 4:5 W.m À2 (Cordonnier et al 2012b). We note that the Brinkman number curve consistently divides the regimes of purely isothermal experiments and those with measurable heat gain.…”

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 99%

“…In single-phase liquids at Deborah numbers below the critical threshold at which fracturing is observed, there is evidence that during steady state shearing flow, there is a non-Newtonian relationship between applied shear stress and resultant shear rate of strain (Simmons et al 1982;Dingwell and Webb 1989;Webb and Dingwell 1990a;Cordonnier et al 2012b). In the onset of this non-Newtonian, the onset of this non-Newtonian behaviour appears to be well described by the value above which viscous dissipation of heat is active on the system length scale of interest (Costa and Macedonio 2005;Hess et al 2008).…”

Section: Apparent Non-newtonian Effectsmentioning

confidence: 99%

“…Using single-phase liquids, there are two dominant geometries: (1) thin fibers of silicate liquid of basaltic, andesitic, phonolitic and rhyolitic composition were stretched under constant load in tension until the fibers snapped in a singular fracture event (Webb and Dingwell 1990b), and (2) cylinders of synthetic borosilicate liquid were compressed under constant load and the bulk temporal evolution of the rate of axial shortening was determined as viscous (relaxed) if it continuously increased to a steady or near-steady value, or brittle (unrelaxed) if the axial shortening rate jumped due to fracturing events (Cordonnier et al 2012b). In another type of experiment, analogue vesicular liquids were decompressed at different rates from pressure (Kameda and Kuribara 2008;Kameda et al 2013).…”

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 99%

“…In the viscous field, Cordonnier et al (2012b) additionally recorded whether samples hosted a measurable temperature increase due to viscous dissipation of heat during the experiment, or not. In Fig.…”

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 99%

See 4 more Smart Citations

When Does Magma Break?

Wadsworth¹,

Witcher²,

Vasseur³

et al. 2017

Advances in Volcanology

View full text Add to dashboard Cite

Geophysical signals arriving at the Earth's surface originate from a source mechanism at depth but are not necessarily directly observable. Therefore, well-posed experiments can provide insights into source mechanics and, importantly, the parameters required to model aspects of the sources of unrest signals. In this Chapter we detail one such example of how experimental laboratory work has improved our understanding of unrest signals. We focus on the failure of single-and multi-phase magmas, demonstrating that the liquid viscosity, and therefore the temperature and volatile content of a magma of a given composition, is the limiting parameter in determining whether a magma will ascend viscously or whether it can fracture during ascent. This critical threshold is characterized by a Deborah number, the ratio of the timescale of relaxation to the timescale of local flow. We show that for single-phase magmatic liquids and for vigorously vesiculating magmas, a local Deborah number of 10 À2 is the limit above which mixed viscoelastic behaviour including fracture propagation can be expected, and a Deborah number of 1 is the limit above which magma is dominantly elastic and responds in a brittle manner to applied stresses. These thresholds can be understood in terms of the onset and peak of the Debye relaxation process for viscoelastic liquids. The apparent validity of a Maxwell model permits us to predict the maximum stress that can be supported by a volcanic liquid deforming in the high Deborah number range. We use these constraints to provide a map of timescales on which we contour dominant system responses from viscous to purely brittle; valid for all magmatic liquids. Finally, we explore the scaling necessary to extend these conceptual insights to crystal-and bubble-bearing magmas valid under specific conditions. The competing timescales of deformation and relaxation in magma are relevant to unrest source mechanisms that originate from magma deformation, such as long-period seismic signals that are used to predict eruption timing. KeywordsRheology Á Strain rate Á Experimental volcanology Á Glass transition Á Failure forecasting Á Low frequency earthquakes Á Viscous dissipation Glossary RheologyThe study of the response of a material to an applied stress or deformation. In the volcano-sciences this typically refers to magma-rheology which is dominated by the rheology of the liquid phase (a viscous or viscoelastic melt) and the additional effect of suspended phases (crystals and gases). Viscoelasticity A material response to an applied stress in which both elastic and viscous components of the deformation are observed. In magma, as the temperature decreases or the local strain rate increases, the elastic component becomes more dominant. When the viscous component is negligible, purely elastic behaviour and material-rupture can readily occur. See Rheology.

show abstract

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 97%

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 99%

Section: Apparent Non-newtonian Effectsmentioning

confidence: 99%

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 99%

Section: The Universal Breaking Timescales Of Volcanic Liquidsmentioning

confidence: 99%

See 3 more Smart Citations

When Does Magma Break?

Wadsworth¹,

Witcher²,

Vasseur³

et al. 2017

Advances in Volcanology

View full text Add to dashboard Cite

show abstract

Volcanic sintering: Timescales of viscous densification and strength recovery

Vasseur

Wadsworth

Lavallée

et al. 2013

Geophysical Research Letters

View full text Add to dashboard Cite

[1] Sintering and densification are ubiquitous processes influencing the emplacement of both effusive and explosive products of volcanic eruptions. Here we sinter ash-size fragments of a synthetic National Institute of Standards and Technology viscosity standard glass at temperatures at which the resultant melt has a viscosity of ∼108–109 Pa.s at 1bar to assess sintering dynamics under near-surface volcanic conditions. We track the strength recovery via uniaxial compressive tests. We observe that volcanic ash sintering is dominantly time dependent, temperature dependent, and grain size dependent and may thus be interpreted to be controlled by melt viscosity and surface tension. Sintering evolves from particle agglutination to viscous pore collapse and is accompanied by a reduction in connected porosity and an increase in isolated pores. Sintering and densification result in a nonlinear increase in strength. Micromechanical modeling shows that the pore-emanated crack model explains the strength of porous lava as a function of pore fraction and size.

show abstract

Nonisothermal viscous sintering of volcanic ash

et al. 2014

View full text Add to dashboard Cite

Volcanic ash is often deposited in a hot state. Volcanic ash containing glass, deposited above the glass transition interval, has the potential to sinter viscously both to itself (particle‐particle) and to exposed surfaces. Here we constrain the kinetics of this process experimentally under nonisothermal conditions using standard glasses. In the absence of external load, this process is dominantly driven by surface relaxation. In such cases the sintering process is rate limited by the melt viscosity, the size of the particles and the melt‐vapor interfacial tension. We propose a polydisperse continuum model that describes the transition from a packing of particles to a dense pore‐free melt and evaluate its efficacy in describing the kinetics of volcanic viscous sintering. We apply our model to viscous sintering scenarios for cooling crystal‐poor rhyolitic ash using the 2008 eruption of Chaitén volcano as a case example. We predict that moderate linear cooling rates of > 0.1°C min−1 can result in the common observation of incomplete sintering and the preservation of pore networks.

show abstract

Viscous heating in silicate melts: An experimental and numerical comparison

Cited by 44 publications

References 69 publications

When Does Magma Break?

When Does Magma Break?

Volcanic sintering: Timescales of viscous densification and strength recovery

Nonisothermal viscous sintering of volcanic ash

Contact Info

Product

Resources

About