DOI: 10.5281/zenodo.15530537
title: Data archive and R notebook visualization toolkit for "Titan's Refractory Core Evolution: Implications for Organics in its Subsurface Ocean"

description: This repository contains:



Condensed data ("titan_data.zip") to reproduce the figures in the manuscript "Titan's Refractory Core Evolution: Implications for Organics in its Subsurface Ocean" by K. E. Miller et al., related to interior evolution, i.e., phase assemblage for Cases A, B and C, and extracted and retained elemental masses over Titan's thermal evolution. The "data_manifest.csv" documents what each file is.

A R notebook ("Titan_interior_evolution_visualization_toolkit.Rmd") that uses the uncompressed "titan_data" folder, placed in the same path, to faciliate plotting all the relevant figures. This notebook has been coded for ease of use, to plot figures identical or similar to those for interior phase assemblages, element extraction and retention as in the manuscript.

Compressed raw output Project files from the Rcrust program ("Rcrust_data_files.zip"), for Cases A, B, and C, originally known as "Titan_100CI_DEW19_713_20230914_Extract100_v1", "Titan_case8_DEW19_713_20230914_Extract100_v7", and "Titan_case11_DEW19_713_20230914_Extract100_v2" respectively. These can be used to check the original model outcomes, used for subsequent analyses of the phase assemblage, and extracted and retained elements.

Rcrust/Perple_X thermodynamic data file, solution model file, option file, and used 64-bit Windows meemum executable, all compressed into "Rcrust_data_files.zip" These are used by Rcrust/Perple_X to reproduce the models.

Another R notebook ("titan_transport_calculator.Rmd") containing Stokes settling and Darcy flow calculations to demonstrate that instantaneous fluid extraction from the interior to the burgeoning hydrosphere assumed in the thermodynamic models is justified compared to the 100-Myr-thermal evolution model time step.


Perple_X is suite of programs that perform Gibbs free energy minimization (among other things) to predict stable phase equilibria with thermodynamics, for geologic settings. Perple_X can be found here:

Relevant references are: 

Connolly, J.A.D., 2009. The geodynamic equation of state: What and how. Geochemistry, Geophysics, Geosystems 10, Q10014. https://doi.org/10.1029/2009GC002540Connolly, J.A.D., 2005. Computation of phase equilibria by linear programming: A tool for geodynamic modeling and its application to subduction zone decarbonation. Earth and Planetary Science Letters 236, 524–541. https://doi.org/10.1016/j.epsl.2005.04.033Connolly, J.A.D., Galvez, M.E., 2018. Electrolytic fluid speciation by Gibbs energy minimization and implications for subduction zone mass transfer. Earth and Planetary Science Letters 501, 90–102. https://doi.org/10.1016/j.epsl.2018.08.024

Rcrust is a wrapper program for Perple_X, to facilitate pressure-temperature pathway modeling with phase (e.g., fluid, melt, mineral) fractionation. Rcrust can be found here: https://www.sun.ac.za/english/faculty/science/earthsciences/Pages/Rcrust-3.aspx

Relevant references are: 

Mayne, M.J., Moyen, J.-F., Stevens, G., Kaislaniemi, L., 2016. Rcrust: a tool for calculating path-dependent open system processes and application to melt loss. Journal of Metamorphic Geology 34, 663–682. https://doi.org/10.1111/jmg.12199

Mayne, M.J., Stevens, G., Moyen, J.-F., Johnson, T., 2019. Performing process-oriented investigations involving mass transfer using Rcrust: a new phase equilibrium modelling tool. Geological Society, London, Special Publications 491, SP491-2018–85. https://doi.org/10.1144/SP491-2018-85