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Updated: Jul 6, 2026
10:18
Dynamic Pore-scale Reservoir-condition Imaging of Reaction in Carbonates Using Synchrotron Fast Tomography
Published on: February 21, 2017
A 'dry' condensation origin for circumstellar carbonates
Alice Toppani1, François Robert, Guy Libourel
1Centre de Recherches Pétrographiques et Géochimiques-CNRS UPR 2300, 15 rue Notre Dame des Pauvres, BP 20, Vandoeuvre-les-Nancy, France. toppani2@llnl.gov
Nature
|October 21, 2005
Summary
Carbonate minerals, previously linked to water, can form abiogenically with silicates in space. This finding suggests new origins for cosmic carbonates in hot, dense stellar environments.
Area of Science:
- Astrochemistry
- Planetary Science
- Mineralogy
Background:
- Carbonate minerals are detected in astrophysical environments like protostars.
- Abiogenic carbonates typically indicate aqueous alteration with CO2-rich water.
- Recent detections in planetary nebulae and protostars challenge this indicator's relevance.
Purpose of the Study:
- To investigate an alternative formation pathway for astrophysical carbonates.
- To explore the role of non-equilibrium condensation in carbonate formation.
- To understand the origin of carbonates in environments lacking liquid water.
Main Methods:
- Experimental simulation of non-equilibrium condensation.
- Condensation of silicate gas in a H2O-CO2-rich vapor.
- Analysis of co-condensed amorphous silicates and carbonates.
Main Results:
- Demonstrated abiogenic formation of carbonates alongside amorphous silicates.
- Successful co-condensation occurred during non-equilibrium processes.
- Identified conditions favoring carbonate formation without liquid water.
Conclusions:
- Astrophysical carbonates may form via non-equilibrium condensation in space.
- Proposed formation sites include evolved stellar winds and protostellar outflows.
- This provides an alternative explanation for observed cosmic carbonates.
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