Lithosphere and Mantle Evolution Model (LaMEM): v3.0.0

The Lithosphere and Mantle Evolution Model (LaMEM; Kaus et al., 2016) is a parallel thermo-mechanical code designed for a wide range of geomechanical and geotechnical applications involving rocks and soils with highly nonlinear visco-elasto-plastic rheologies. The code primarily targets the simulation of geological processes related to crustal dynamics and lithosphere-mantle interactions, while also supporting several geotechnical applications. LaMEM employs a stable, lightweight staggered-grid finite-difference discretization combined with a marker-in-cell technique for material advection. The code is built on the highly efficient PETSc (Portable, Extensible Toolkit for Scientific Computation) library (Balay et al., 2025), enabling near-optimal scaling on massively parallel computing architectures. PETSc further provides a comprehensive suite of algorithms and data structures for the solution of linear and nonlinear systems. To accelerate large-scale simulations, custom Galerkin coarsening operators have been integrated into the PETSc multigrid framework. LaMEM is distributed under the MIT license and is openly available on GitHub at https://github.com/UniMainzGeo/LaMEM.

In this contribution, we announce an upcoming major release of LaMEM (v3.0.0), which introduces substantial enhancements in both functionality and computational performance. We provide a concise overview of the key developments in this release, including: periodic boundary conditions; a hybrid Galerkin/matrix-free multigrid framework; two-dimensional multigrid coarsening; block factorization and wBFBT preconditioners; improved default solver configurations; and automatic stopping tolerances.

References

Balay, S., Abhyankar, S., Adams, M. F., Benson, S., Brown, J., Brune, P., Buschelman, K., Constantinescu, E., Dalcin, L., Dener, A., Eijkhout, V., Faibussowitsch, J., Gropp, W. D., Hapla, V., Isaac, T., Jolivet, P., Karpeev, D., Kaushik, D., Knepley, M. G., Kong, F., Kruger, S., May, D. A., McInnes, L. C., Mills, R. T., Mitchell, L., Munson, T., Roman, J. E., Rupp, K., Sanan, P., Sarich, J., Smith, B. F., Suh, H., Zampini, S., Zhang, H., Zhang, H., Zhang, J., 2025. PETSc/TAO Users Manual, Tech. Rep. ANL-21/39 - Revision 3.23. Argonne National Laboratory.

Kaus, B. J. P., Popov, A. A., Baumann, T. S., Pusok, A. E., Bauville, A., Fernandez, N., Collignon, M., 2016. Forward and Inverse Modelling of Lithospheric Deformation on Geological Timescales. NIC Series, 48, 299-307.