Lucky box model for mantle evolution

I have developed a model to simulate variable degrees of mantle melting since 4.4 Ga. The present model explicitly tracks variable degrees of melt depletion and refertilization in more than 26,000 parcels representing the chemically diverse peridotitic mantle. We assume uniform primitive mantle 4.55 billion years ago and simplify the effect of mantle convection by setting a remelting interval and allowing a proportion of newly produced oceanic residual parcels to subduct into lower mantle. In exchange for down-going mass, the same amount of parcels from the lower mantle enters the upper mantle.

The code is compatible with Python 3.12.0
(1) Run batch_parallel.py to simulates mantle evolution.
The two important model parameters are:
'phase_1_rate_relative_values': [1], # the rate of global melting in the first stage relative to present day
'oceanic_deep_subduction_p_values': [0.2], # the likelihood of subducting oceanic mantle to lower mantle

The default model considers slow diffusion of HFSE. If you want to choose equilibrium melting, change HFSE_DK to 0 in mantle_geochem_constants.py

(2) Run batch_plot.py to plot results of trace elements and Nd-Hf isotope ratios.