ASPECT v2.4.0

We are pleased to announce the release of ASPECT 2.4.0. ASPECT is the Advanced
Solver for Problems in Earth's ConvecTion. It uses modern numerical methods such
as adaptive mesh refinement, multigrid solvers, and a modular software design to
provide a fast, flexible, and extensible mantle convection solver. ASPECT is
available from

               https://aspect.geodynamics.org/

and the release is available from

    https://geodynamics.org/resources/aspect

and

    https://github.com/geodynamics/aspect/releases/tag/v2.4.0

Among others this release includes the following significant changes:

• New: ASPECT now requires deal.II 9.3.0 or newer, and cmake 3.1.0 or newer.
  (Timo Heister)

• New: The matrix-free GMG Stokes solver now works for problems with
  free-surface boundaries and elasticity.
  (Jiaqi Zhang, Anne Glerum, Timo Heister, John Naliboff)

• New: The matrix-free GMG Stokes preconditioner is now implemented for the
  Newton solver.
  (Timo Heister, Menno Fraters, Jiaqi Zhang)

• New: Visualization postprocessors now record the physical units of the
  quantity they compute, and this information is also output into visualization
  files with a sufficiently new version of deal.II.
  (Wolfgang Bangerth)

• New: Where possible, when using large data tables as input (e.g., for initial
  conditions specified as tables), these data are now stored only once on each
  node in memory areas that is accessible by all MPI processes on that node.
  (Wolfgang Bangerth)

• New: There is now a new material model for melting in the lowermost mantle.
  It can be used to reproduce the results of Dannberg et al. (2021).
  (Juliane Dannberg)

• New: The geoid postprocessor can now handle a deforming mesh, in addition to the
  already existing option from the dynamic topography postprocessor output.
  (Maaike Weerdesteijn, Rene Gassmoeller, Jacky Austermann)

• New: There is now a 'static' option for the temperature field that is set-up
  similarly to the 'static' option for compositional fields. This allows the
  temperature field to be constant over time so you can still advect and build
  up elastic stresses.
  (Rebecca Fildes, Magali Billen)

• Changed: The least squares particle interpolation plugins now provide a bound
  preserving slope limiter that respects local bounds on each cell.
  (Mack Gregory, Gerry Puckett, Rene Gassmoeller)

• New: Add an advection field method that advects a compositional field
  according to Darcy's Law.
  (Daniel Douglas)

• New: The material model 'dynamic_friction' has been integrated into a new
  rheology model friction_models that can be used together with the
  visco_plastic material model.
  (Esther Heckenbach)

• New: ASPECT now has a ThermodynamicTableLookup equation of state plugin,
  which allows material models to read in one or more Perple_X or HeFESTo table
  files.
  (Bob Myhill)

• Changed: The initial composition model called 'ascii data' can now read in 3d
  ascii datasets into a 2d model and slice the dataset in a user controlled
  plane. This allows it to make high-resolution 2d models of problems that use
  observational data (such as seismic tomography models).
  (Juliane Dannberg, Rene Gassmoeller)

• New: Added a new postprocessor which computes the parameter "Mobility"
  following Lourenco et al., 2020.
  (Elodie Kendall, Rene Gassmoeller, Anne Glerum and Bob Myhill)

• Improved: Particle operations have been significantly accelerated, in
  particular in combination with a recent deal.II version (9.4.0 or newer).
  (Rene Gassmoeller)

• New: Add a benchmark for load induced flexure with options for specifying
  sediment and rock material infilling the flexural moat.
  (Daniel Douglas)

• New: ASPECT now has a cookbook that uses the gravity postprocessor to
  compute gravity generated by S40RTS-based mantle density variations.
  (Cedric Thieulot)

• New: ASPECT now has a cookbook that shows how velocities can be prescribed
  at positions specified by an ASCII input file.
  (Bob Myhill)

• New: There is now a cookbook of kinematically driven oceanic subduction in 2D
  with isoviscous materials and without temperature effects. The cookbook model
  setup is based on Quinquis (2014).
  (Anne Glerum)

• New: There is now a cookbook that visualizes the phase diagram from results
  of a model run. This includes examples from the Visco-Plastic and Steinberger
  material model.
  (Haoyuan Li and Magali Billen)

• New: There is now a cookbook that reproduces convection models with a phase
  function from Christensen and Yuen, 1985.
  (Juliane Dannberg)

• Fixed: Many bugs, see link below for a complete list.
  (Many authors. Thank you!).

A complete list of all changes and their authors can be found at
https://aspect.geodynamics.org/doc/doxygen/changes_between_2_83_80_and_2_84_80.html

Wolfgang Bangerth, Juliane Dannberg, Menno Fraters, Rene Gassmoeller,
Anne Glerum, Timo Heister, Bob Myhill, John Naliboff,
and many other contributors.