We illustrate the flow behaviour of fluids with isotropic and anisotropic microstructure (interna... more We illustrate the flow behaviour of fluids with isotropic and anisotropic microstructure (internal length, layering with bending stiffness) by means of numerical simulations of silo discharge and flow alignment in simple shear. The Cosserat theory is used to provide an internal length in the constitutive model through bending stiffness to describe isotropic microstructure and this theory is coupled to a director theory to add specific orientation of grains to describe anisotropic microstructure. The numerical solution is based on an implicit form of the Material Point Method developed by Moresi et al. [[1]].
Legacy release of UW1. Please consider migrating to Underworld version 2 If you use UW1, please c... more Legacy release of UW1. Please consider migrating to Underworld version 2 If you use UW1, please cite the following paper: Moresi, L., Moresi, L. N., S. Quenette, V. Lemiale, C. Mériaux, B. Appelbe, W. Appelbe, H. B. Muhlhaus, Mühlhaus (2007), Computational approaches to studying non-linear dynamics of the crust and mantle, Physics of the Earth and Planetary Interiors, 163(1-4), 69–82, doi:10.1016/j.pepi.2007.06.009. There is a DOI for the UW1 code itself: DOI: 10.5281/zenodo.1445812
Recent geophysical observations report the presence of a very weak and thin upper asthenosphere u... more Recent geophysical observations report the presence of a very weak and thin upper asthenosphere underneath subducting oceanic plates at convergent margins. Along these margins, trench migrations are significantly slower than plate convergence rates. We use numerical models to assess the role of a weak upper asthenospheric layer on plate and trench motions. We show that the presence of this layer alone can enhance an advancing trend for the motion of the plate and hamper trench retreat. This mechanism provides a novel and alternative explanation for the slow rates of trench migration and fast‐moving plates observed globally at natural subduction zones.
Carbon dioxide (CO<sub>2</sub>) liberated at arc volcanoes that intersect buried carb... more Carbon dioxide (CO<sub>2</sub>) liberated at arc volcanoes that intersect buried carbonate platforms plays a larger role in influencing atmospheric CO<sub>2</sub> than those active margins lacking buried carbonate platforms. This study investigates the contribution of carbonate-intersecting arc activity on palaeo-atmospheric CO<sub>2</sub> levels over the past 410 million years by integrating a plate motion model with an evolving carbonate platform development model. Our modelled subduction zone lengths and carbonate-intersecting arc lengths approximate arc activity with time, and can be used as input into fully-coupled models of CO<sub>2</sub> flux between deep and shallow reservoirs. Continuous and cross-wavelet as well as wavelet coherence analyses were used to evaluate trends between carbonate-intersecting arc activity, non-carbonate-intersecting arc activity and total global subduction zone lengths and the proxy-CO<sub>2<...
Springer Series in Geomechanics and Geoengineering, 2011
In this paper, we will explore the role of non-coaxiality on shear banding in pure shear. We firs... more In this paper, we will explore the role of non-coaxiality on shear banding in pure shear. We first outline the consitituve relations. The deformation and localization process is illustrated by results of large deformation finite element simulations on a rectangular domain in extension for different constitutive models. We also show the variation of the average horizontal stress (stress resultant) conjugate
The Earth shows different modes of deformation in response to thermal or gravitational driving fo... more The Earth shows different modes of deformation in response to thermal or gravitational driving forces. The bulk mantle convects like a viscous fluid on the global scale, while the lithosphere is broken into several plates. They show little internal deformation, but change their shapes and relative positions. Oceanic plate material is generated at divergent margins and recycled into the mantle at subduction zones, on a regional scale. The buoyant continental crust resists subduction and develops meter-scale shear bands during deformation.
We illustrate the flow behaviour of fluids with isotropic and anisotropic microstructure (interna... more We illustrate the flow behaviour of fluids with isotropic and anisotropic microstructure (internal length, layering with bending stiffness) by means of numerical simulations of silo discharge and flow alignment in simple shear. The Cosserat theory is used to provide an internal length in the constitutive model through bending stiffness to describe isotropic microstructure and this theory is coupled to a director theory to add specific orientation of grains to describe anisotropic microstructure. The numerical solution is based on an implicit form of the Material Point Method developed by Moresi et al. [[1]].
Legacy release of UW1. Please consider migrating to Underworld version 2 If you use UW1, please c... more Legacy release of UW1. Please consider migrating to Underworld version 2 If you use UW1, please cite the following paper: Moresi, L., Moresi, L. N., S. Quenette, V. Lemiale, C. Mériaux, B. Appelbe, W. Appelbe, H. B. Muhlhaus, Mühlhaus (2007), Computational approaches to studying non-linear dynamics of the crust and mantle, Physics of the Earth and Planetary Interiors, 163(1-4), 69–82, doi:10.1016/j.pepi.2007.06.009. There is a DOI for the UW1 code itself: DOI: 10.5281/zenodo.1445812
Recent geophysical observations report the presence of a very weak and thin upper asthenosphere u... more Recent geophysical observations report the presence of a very weak and thin upper asthenosphere underneath subducting oceanic plates at convergent margins. Along these margins, trench migrations are significantly slower than plate convergence rates. We use numerical models to assess the role of a weak upper asthenospheric layer on plate and trench motions. We show that the presence of this layer alone can enhance an advancing trend for the motion of the plate and hamper trench retreat. This mechanism provides a novel and alternative explanation for the slow rates of trench migration and fast‐moving plates observed globally at natural subduction zones.
Carbon dioxide (CO<sub>2</sub>) liberated at arc volcanoes that intersect buried carb... more Carbon dioxide (CO<sub>2</sub>) liberated at arc volcanoes that intersect buried carbonate platforms plays a larger role in influencing atmospheric CO<sub>2</sub> than those active margins lacking buried carbonate platforms. This study investigates the contribution of carbonate-intersecting arc activity on palaeo-atmospheric CO<sub>2</sub> levels over the past 410 million years by integrating a plate motion model with an evolving carbonate platform development model. Our modelled subduction zone lengths and carbonate-intersecting arc lengths approximate arc activity with time, and can be used as input into fully-coupled models of CO<sub>2</sub> flux between deep and shallow reservoirs. Continuous and cross-wavelet as well as wavelet coherence analyses were used to evaluate trends between carbonate-intersecting arc activity, non-carbonate-intersecting arc activity and total global subduction zone lengths and the proxy-CO<sub>2<...
Springer Series in Geomechanics and Geoengineering, 2011
In this paper, we will explore the role of non-coaxiality on shear banding in pure shear. We firs... more In this paper, we will explore the role of non-coaxiality on shear banding in pure shear. We first outline the consitituve relations. The deformation and localization process is illustrated by results of large deformation finite element simulations on a rectangular domain in extension for different constitutive models. We also show the variation of the average horizontal stress (stress resultant) conjugate
The Earth shows different modes of deformation in response to thermal or gravitational driving fo... more The Earth shows different modes of deformation in response to thermal or gravitational driving forces. The bulk mantle convects like a viscous fluid on the global scale, while the lithosphere is broken into several plates. They show little internal deformation, but change their shapes and relative positions. Oceanic plate material is generated at divergent margins and recycled into the mantle at subduction zones, on a regional scale. The buoyant continental crust resists subduction and develops meter-scale shear bands during deformation.
There are two ways to interpret a title such as " A Plug-in based design for code maintainability... more There are two ways to interpret a title such as " A Plug-in based design for code maintainability in HPC " , based on whether you are: through and through a HPC traditionalist, and then there is everybody else. But with realisation of computer software development cost, the commoditisation of clustering and the requirement of cross disciplinary science, scientific code evolution and maintenance for researchers is a real issue. This paper investigates what performance costs does one bare for the flexibility and maintainability of HPC software. If we can't be fully flexible, what can be? With all modern HPC platforms facilitating expected features such as dynamic libraries, concepts such as plugins can be considered. We explain how and where and why such concepts may be utilised. Then we offer two indicative examples of two very differently formulated scientific codes.
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Papers by Louis Moresi