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Adiabatic Processes for an Ideal Gas

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Related Experiment Video

Updated: May 30, 2026

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO₂/Organic/Water Systems

Published on: January 24, 2014

Triassic-Jurassic atmospheric CO2 spike.

Gregory J Retallack

|January 25, 2002

Summary

This study challenges the idea of constant atmospheric CO2 during the Triassic-Jurassic boundary. Stratigraphic issues and methane contamination may affect previous findings on carbon dioxide levels.

Area of Science:

Paleoclimatology
Geochemistry
Stratigraphy

Background:

The Triassic-Jurassic boundary marks a significant period of environmental change.
Previous research by Tanner et al. suggested stable atmospheric CO2 levels across this boundary.
Palaeosol carbonate carbon-isotope composition is often used to reconstruct past atmospheric CO2.

Discussion:

This research questions the stratigraphic completeness of key geological sections used in prior studies.
Contamination from atmospheric methane, which has a light isotopic signature, can interfere with CO2 reconstructions.
The oxidation of methane to CO2 can obscure signals of methane-clathrate dissociation events.

Key Insights:

Tanner et al.'s claim of constant atmospheric CO2 across the Triassic-Jurassic boundary is challenged.

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High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

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Stratigraphic uncertainties and methane contamination are identified as critical limitations in previous analyses.

The reliability of palaeosol carbonate carbon isotopes as a proxy for CO2 is questioned under specific conditions.

Outlook:

Further research is needed to refine stratigraphic correlations and assess methane's impact on CO2 proxies.
Improved methods for detecting methane-derived carbon signals are crucial for accurate paleoclimatic reconstructions.
Re-evaluation of atmospheric CO2 dynamics during the Triassic-Jurassic transition is warranted.