Inspecting the Geochemical Flux of Europa from its Thermal Evolution
Abstract
Europa poses novel questions regarding astrobiology and habitability due to its liquid water ocean. Defining the nature of geochemical fluxes within Europa in the context of the thermal evolution of the satellite is a necessary perspective in understanding the potential for habitability. While many theories and models exist for plausible Europa geochemical processes and interactions, few incorporate the non-static nature of heat production in the interior through time. Work on the thermal-orbital history of Europa show periods of oscillatory heat production rates due to tidal and radiogenic heating. These variations in heat production could have non-negligible effects on the geochemical systems within the interior of Europa. Due to the complexity modeling geochemical cycles, the geochemical kinematics will be realized through a box model. Box models have been successfully used in modeling for Earth's ocean cycling and terrestrial exoplanets. Box-models divide the system into well-mixed reservoirs, or 'boxes', with fluxes between each box driven by mass-balance. The simplicity allows for realistically-solvable equations, enabling a focus on fundamental interactions while minimizing computational time. The thermal evolution of Europa is modeled through a one-dimensional, depth-dependent temperature profile. Radiogenic and tidal heat production are considered. Both conductive and convective scenarios are considered for the mantle and ocean. The Europan box-model consists of five boxes (upper ice, lower ice, ocean, mantle, core) and iteratively calculates the chemical mass fluxes, incorporating the temperature profiles into the chemical species EOS, through time. Carbon, oxygen, and hydrogen fluxes will be demonstrated, and consequently the production and circulation of carbon dioxide, carbon monoxide, and methane. These are important participants in water-rock reactions at varying temperatures and have likely played an important part in the evolution of the biosphere on Earth. Additionally, geothermal processes dependent on these species, such as serpentinization, hydro-thermalism, and H2 outgassing would create an effect on the long-term heat production in the interior.
- Publication:
-
AAS/Division for Planetary Sciences Meeting Abstracts #50
- Pub Date:
- October 2018
- Bibcode:
- 2018DPS....5041505S