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Updated: May 27, 2026
06:29
Simulation of Early Earth Hydrothermal Chimneys in a Thermal Gradient Environment
Published on: February 27, 2021
Modeling free energy availability from Hadean hydrothermal systems to the first metabolism
E Simoncini1, M J Russell, A Kleidon
1Max Planck Institut für Biogeochemie, Hans-Knöll-Strasse 10, Jena, 07745, Germany. esimon@bgc-jena.mpg.de
Summary
Off-axis hydrothermal systems (HSs) offer the greatest potential for life's emergence by maximizing abiotic geochemical free energy generation. Convection in these systems enhances energy production, making them ideal for early metabolic pathways.
Area of Science:
- Geochemistry
- Astrobiology
- Thermodynamics
Background:
- Off-axis hydrothermal systems (HSs) are considered potential settings for the origin of life.
- Metabolism requires a continuous supply of free energy, driving research into geological energy generation.
Purpose of the Study:
- To investigate conditions favoring maximal free energy generation by geologic processes.
- To relate these conditions to those found in off-axis HSs for life's emergence.
Main Methods:
- Development of a conceptual model analyzing the energetics of fluid motion and exothermic reactions.
- Explicitly capturing the interaction between convection and chemical kinetics to maintain disequilibrium.
Main Results:
- A positive feedback loop between convection and chemical kinetics in HSs significantly increases free energy generation rates.
- Off-axis HSs, with lower temperatures and dynamics-driven reaction temperatures, exhibit greater geochemical free energy generation.
Conclusions:
- Off-axis HSs provide the highest rates of abiotic geochemical free energy generation.
- These conditions are hypothesized to be most conducive for the emergence of protometabolic pathways.
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