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Abstract Although many collisional orogens form after subduction of oceanic lithosphere between two continents, some orogens result from strain localization within a continent via inversion of structures inherited from continental rifting. Intracontinental rift-inversion orogens exhibit a range of structural styles, but the underlying causes of such variability have not been extensively explored. We use numerical models of intracontinental rift inversion to investigate the impact of parameters including rift structure, rift duration, post-rift cooling, and convergence velocity on orogen structure. Our models reproduce the natural variability of rift-inversion orogens and can be categorized using three endmember styles: asymmetric underthrusting (AU), distributed thickening (DT), and localized polarity flip (PF). Inversion of narrow rifts tends to produce orogens with more localized deformation (styles AU and PF) than those resulting from wide rifts. However, multiple combinations of the parameters we investigated can produce the same structural style. Thus, our models indicate no unique relationship between orogenic structure and the conditions prior to and during inversion. Because the style of rift-inversion orogenesis is highly contingent upon the rift history prior to inversion, knowing the geologic history that preceded rift inversion is essential for translating orogenic structure into the processes that produced that structure. 

We are pleased to announce the release of ASPECT 2.5.0. 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/v2.5.0 Among others this release includes the following significant changes: ASPECT now includes version 0.5.0 of the Geodynamic World Builder. (Menno Fraters and other contributors) ASPECT's manual has been converted from LaTeX to Markdown to be hosted as a website at https://aspect-documentation.readthedocs.io. (Chris Mills, Mack Gregory, Timo Heister, Wolfgang Bangerth, Rene Gassmoeller, and many others) New: ASPECT now requires deal.II 9.4 or newer. (Rene Gassmoeller, Timo Heister) ASPECT now supports a DebugRelease build type that creates a debug build and a release build of ASPECT at the same time. It can be enabled by setting the CMake option CMAKE_BUILD_TYPE to DebugRelease or by typing "make debugrelease". (Timo Heister) ASPECT now has a CMake option ASPECT_INSTALL_EXAMPLES that allows building and install all cookbooks and benchmarks. ASPECT now additionally installs the data/ directory. Both changes are helpful for installations that are used for teaching and tutorials. (Rene Gassmoeller) Changed: ASPECT now releases the memory used for storing initial conditions and the Geodynamic World Builder after model initialization unless an owning pointer to these objects is kept. This reduces the memory footprint for models initialized from large data files. (Wolfgang Bangerth) Added: Various helper functions to distinguish phase transitions for different compositions and compositional fields of different types. (Bob Myhill) Added: The 'adiabatic' initial temperature plugin can now use a spatially variable top boundary layer thickness read from a data file or specified as a function in the input file. Additionally, the boundary layer temperature can now also be computed following the plate cooling model instead of the half-space cooling model. (Daniel Douglas, John Naliboff, Juliane Dannberg, Rene Gassmoeller) New: ASPECT now supports tangential velocity boundary conditions with GMG for more geometries, such as 2D and 3D chunks. (Timo Heister, Haoyuan Li, Jiaqi Zhang) New: Phase transitions can now be deactivated outside a given temperature range specified by upper and lower temperature limits for each phase transition. This allows implementing complex phase diagrams with transitions that intersect in pressure-temperature space. (Haoyuan Li) New: There is now a postprocessor that outputs the total volume of the computational domain. This can be helpful for models using mesh deformation. (Anne Glerum) New: Added a particle property 'grain size' that tracks grain size evolution on particles using the 'grain size' material model. (Juliane Dannberg, Rene Gassmoeller) 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_84_80_and_2_85_80.html Wolfgang Bangerth, Juliane Dannberg, Menno Fraters, Rene Gassmoeller, Anne Glerum, Timo Heister, Bob Myhill, John Naliboff, and many other contributors. 

Abstract. Geodynamic modelling provides a powerful tool to investigate processes in the Earth's crust, mantle, and core that are not directly observable. However, numerical models are inherently subject to the assumptions and simplifications on which they are based. In order to use and review numerical modelling studies appropriately, one needs to be aware of the limitations of geodynamic modelling as well as its advantages. Here, we present a comprehensive yet concise overview of the geodynamic modelling process applied to the solid Earth from the choice of governing equations to numerical methods, model setup, model interpretation, and the eventual communication of the model results. We highlight best practices and discuss their implementations including code verification, model validation, internal consistency checks, and software and data management. Thus, with this perspective, we encourage high-quality modelling studies, fair external interpretation, and sensible use of published work. We provide ample examples, from lithosphere and mantle dynamics specifically, and point out synergies with related fields such as seismology, tectonophysics, geology, mineral physics, planetary science, and geodesy. We clarify and consolidate terminology across geodynamics and numerical modelling to set a standard for clear communication of modelling studies. All in all, this paper presents the basics of geodynamic modelling for first-time and experienced modellers, collaborators, and reviewers from diverse backgrounds to (re)gain a solid understanding of geodynamic modelling as a whole.