Work plan to merge my 3-D free subduction model as cookbook

[lhy11009]

I am in the process of merging my 3-D (and 2-D) free subduction model with @mibillen as a cookbook example into the ASPECT main branch. There are a few key steps involved, and I outline the roadmap below.

1. Handling prescribed conditions

My setup relies on prescribing temperature, viscosity, and composition near the corners of the model. To support this more generally, we are implementing a new plugin system for prescribed conditions in ASPECT. This includes a series of PRs. I am also looking forward to a discussion with @MFraters on how to progress with WorldBuilder in parallel:

• PR introducing the plugin system and the velocity plugin
  Prescribed fields plugins #6660

• PR incorporating the temperature plugin
  prescribed temperature function #6823

• PR to incorporate WorldBuilder as both an indicator and condition for prescribed conditions.

• PR fixes the usage of the prescribed condition with the GMG
  GMG: support prescribed values in parts of domain #6731

• Post-process Visualization of the Prescribed Condition
  Prescribed Solution Post-processor #6882

2. Incorporating a new nonlinear solving scheme

This scheme allows the nonlinear solver to proceed to the next iteration even if the cheap Stokes solve does not reach its tolerance, while skipping the expensive Stokes solve. This has proven to be efficient for my model setup.

• PR to include this as an optional feature
  Tolerate linear solver failure in non-linear schemes #6825

3. Workflow for converting flow law parameters to ASPECT inputs

• Start the conversation and design a community-friendly workflow.

4. Using look-up tables and the dominant phase for rheology

• PR for the discrete phase function
  Discrete phase function #6131
• Test this with my model setup (I previously used a different implementation in my own branch).

5. Including metastable kinetics (nucleation + grain growth)

I have implemented this in my branch, and it reproduces the kinetics described in Karato (2001), based on Riedel & Karato (1996). This component is more complex and would certainly involve changes to multiple files, but my goal is to have it ready before the associated paper is accepted (currently in preparation).

I originally discussed this with @bobmyhill during the 2023 hackathon, and I was wondering whether he might be willing to provide further input or guidance. I learned @buchanankerswell has an implementation in the main branch, so I will figure out how we could cooperate on that.

• Start a discussion on incorporating this into the existing metastable module.

[gassmoeller]

Hi @lhy11009, I took the liberty to update your title to make it clear this is not a report about missing modules, but that you plan on working on these items.

I will look into the PRs as I did before, but a quick note: Regarding point 5 you should probably get in touch with @buchanankerswell. He wrote a cookbook during last years hackathon on metastable phases (https://aspect-documentation.readthedocs.io/en/latest/user/cookbooks/cookbooks/phase_transition_kinetics/doc/phase-transition-kinetics.html) and you may want to coordinate on your efforts. There is nothing preventing us from including several separate approaches to kinetics in ASPECT, it may even be useful (if they have different strengths/weaknesses). I just wanted to make sure you are aware of each others work, and avoid duplicated effort where unnecessary.

[lhy11009]

@gassmoeller Thanks for mentioning @buchanankerswell’s work — I agree it would be great for the two of us to collaborate.
@buchanankerswell I’m very interested in the metastable kinetics you already implemented. Once we’re in contact I can share the documentation for the kinetics I implemented in my own branch. I expect we can have a good discussion after that.

[buchanankerswell]

Hi @lhy11009 and @gassmoeller ,

Thanks for bringing this to my attention. I am happy to discuss potential developments of reaction kinetics in ASPECT.

@lhy11009, feel free to contact me at b.kerswell[at]liverpool.ac.uk and we can follow up. The landscape of kinetics is both large and technical, so having a small dedicated team working on this sounds fun and practical IMO.

Best,

Buchanan