arXiv subjects

Maxime Maurice

Publications and source records attributed to Maxime Maurice.

3 recordsLinked to original sources

arXiv2026

Coupled atmospHere Interior modeL Intercomparison (CHILI). I. Evolutionary Modelling -- Primordial Magma Oceans of Earth and Venus

Earth and Venus represent two evolutionary outcomes arising from initially molten 'magma ocean' periods, followed by lifetimes of chemical and geophysical divergence. Their physics is common to all rocky planets and is accessible to simulations that adopt coupled interior-atmosphere modelling approaches. Our understanding of planet histories and interpretation of current states is dependent on this modelling, yet existing codes vary in their approximations. Here, we present the first results from the Coupled atmospHere Interior modeL Intercomparison (CHILI) project; benchmarking planetary evolution codes in the context of Earth and Venus to identify key model sensitivities. Our 'nominal' Earth models predict magma ocean solidification timescales within 4 Myr of thermal evolution, and are consistent with empirical constraints on Earth's early history. Venus scenarios exhibit more diverse behaviours where prolonged magma ocean stages can be conditionally sustained for 50 Myr. Cooling timescales correlate with initial hydrogen and carbon budgets, but model-specific treatments of volatile partitioning and vertical energy transport introduce substantial inter-model variance. Different parametrisations of mantle geodynamics, convection, melting curves, rheological properties, and radiative transfer give rise to divergent evolutionary behaviours. Discrepancies in atmospheres generated by magma ocean outgassing underscore these differences, although C-H-O compositions with surface pressures exceeding 100 bar are favoured. This intercomparison identifies critical sensitivities in volatile partitioning, escape processes, mantle viscosity, and melting. Validating these treatments is essential for enabling deep insight into the early histories of the Solar System's terrestrial planets, and for drawing meaningful interpretations from ongoing observational exoplanet campaigns.

astro-ph.EP↗

arXiv2025

Coupled atmospHere Interior modeL Intercomparison (CHILI) Protocol Version 1.0: A CUISINES Intercomparison Project of Magma Ocean Models

Spectroscopic characterization of rocky exoplanets with the James Webb Space Telescope has brought the origin and evolution of their atmospheres into the focus of exoplanet science. Time-evolved models of the feedback between interior and atmosphere are critical to predict and interpret these observations and link them to the Solar System terrestrial planets. However, models differ in methodologies and input data, which can lead to significant differences in interpretation. In this paper, we present the experimental protocol of the Coupled atmospHere Interior modeL Intercomparison (CHILI) project. CHILI is an (exo-)planet model intercomparison project within the Climates Using Interactive Suites of Intercomparisons Nested for Exoplanet Studies (CUISINES) framework, which aims to support a diverse set of multi-model intercomparison projects in the exoplanet community. The present protocol includes the initial set of participating magma ocean models, divided into evolutionary and static models, and two types of test categories, one focused on Solar System planets (Earth & Venus) and the other on exoplanets orbiting low-mass M-dwarfs. Both test categories aim to quantify the evolution of key markers of the links between planetary atmospheres and interiors over geological timescales. The proposed tests would allow us to quantify and compare the differences between coupled atmosphere-interior models used by the exoplanet and planetary science communities. Results from the proposed tests will be published in dedicated follow-up papers. To encourage the community to join this comparison effort and as an example, we present initial test results for the early Earth and TRAPPIST-1 b, conducted with models differing in the treatment of energy transport in the planetary interior and atmosphere, surface boundary layer, geochemistry, and the in- and outgassing of volatile compounds.

astro-ph.EP↗

arXiv2023

Redox evolution of the crystallizing terrestrial magma ocean and its influence on atmosphere outgassing

Magma oceans are episodes of large-scale melting of the mantle of terrestrial planets. The energy delivered by the Moon-forming impact induced a deep magma ocean on the young Earth, corresponding to the last episode of core-mantle equilibration. The crystallization of this magma ocean led to the outgassing of volatiles initially present in the Earth's mantle, resulting in the formation of a secondary atmosphere. During outgassing, the magma ocean acts as a chemical buffer for the atmosphere via the oxygen fugacity, set by the equilibrium between ferrous- and ferric-iron oxides in the silicate melts. By tracking the evolution of the oxygen fugacity during magma ocean solidification, we model the evolving composition of a C-O-H atmosphere. We use the atmosphere composition to calculate its thermal structure and radiative flux. This allows us to calculate the lifetime of the terrestrial magma ocean. We find that, upon crystallizing, the magma ocean evolves from a mildly reducing to a highly oxidized redox state, thereby transiting from a CO- and H2-dominated atmosphere to a CO2- and H2O-dominated one. We find the overall duration of the magma ocean crystallization to depend mostly on the bulk H content of the mantle, and to remain below 1.5 millions years for up to 9 Earth's water oceans' worth of H. Our model also suggests that reduced atmospheres emit lower infrared radiation than oxidized ones, despite of the lower greenhouse effect of reduced species, resulting in a longer magma ocean lifetime in the former case. Although developed for a deep magma ocean on Earth, the framework applies to all terrestrial planet and exoplanet magma oceans, depending on their volatile budgets.

astro-ph.EP↗