LYNX (Lithosphere dYnamics Numerical toolboX) is another multiphysics modelling solution developed in Section 4.5 at GFZ. LYNX is also based on the flexible, object-oriented numerical framework MOOSE (developed at the Idaho National Laboratories).

LYNX is a novel numerical simulator for modelling thermo-poromechanical coupled processes driving the deformation dynamics of the lithosphere. The formulation adopted in LYNX relies on an efficient implementation of a thermodynamically consistent visco-elasto-plastic rheology with anisotropic porous-visco-plastic damage feedback. The main target is to capture the multiphysics coupling responsible for semi-brittle and semi-ductile behaviour of porous rocks as also relevant to strain localization and faulting processes. More information on the governing equations, their derivation and their implementation together with a list of synthetic and real case applications can be found in Jacquey and Cacace (2020a) and Jacquey and Cacace (2020b).

Versions
LYNX is available from two repositories:

• GitHub (linked to the DOI 10.5281/zenodo.3355376)
• Any new development is maintained in a GitLab project. In order to get access to the GitLab repository, please contact Dr. Mauro Cacace.

For more information see LYNX at Helmholtz RSD.

User group
International user community from geosciences

Features

• Object-orientation: flexible modular structure within easy to be extended modules by the user
• Geometric agnosticism: 1D/2D/3D Finite Elements from the user required
• Hybrid parallelism: multi-threading and MPI
• Proved scalability on HPC architectures - JUWELS cluster Module at JSC

Realistic physics-based rheological description of lithosphere deformation dynamics based on:

• Explicit incorporation of the lithosphere visco-elasto-plastic rheology including nonlinear feedback effects from the energetics of the system
• its extension to account for time-dependent brittle behavior via an overstress (viscoplastic) formulation
• Thermodynamically consistent formulation of semi-brittle semi-ductile deformation modes - brittle deformation via damage mechanics and for ductile deformation via a rate-dependent viscoplastic formulation
• Poro-damage feedback via dynamic porosity (volumetric mechanical response)
• Implicit and efficient numerical implementation within a limited amount of internal iterations
• Use of Automatic Differentation techniques to compute the full Jacobian contribution of the system matrix