Generally, there are three potential carbon sources for authigenic carbonate: (1) seawater DIC, (2) remineralized organic carbon, and (3) remineralized methane carbon.
Oxygen has a spectral fingerprint, as does methane, carbon dioxide and other gases found in atmospheres.
Biogas is composed of methane, carbon dioxide and trace amounts of hydrogen sulfide.
When the temperature gets dialed down low enough for methane, carbon monoxide and nitrogen to become ice, things get weird.
Comotti, A., Bracco, S., Distefano, G. & Sozzani, P. Methane, carbon dioxide and hydrogen storage in nanoporous dipeptide-based materials.
Methane, carbon monoxide, carbon dioxide and nitrogen, all gaseous on Earth, are rendered solid with Pluto's temperatures near absolute zero.
Fortunately, microorganisms can also use cheap, renewable substrates, such as food wastes, biogas methane, carbon dioxide and renewable hydrogen.
In contrast to hydrogen and methane, carbon dioxide can be generated by a number of processes, not just bacterial metabolism.
When the fires penetrate the earth, they smoulder for weeks, sometimes months, releasing clouds of methane, carbon monoxide, ozone and exotic gases such as ammonium cyanide.
As organic waste in a landfill breaks down, it produces landfill gas, a mix of methane, carbon dioxide and water vapor.
The biogas (primarily methane, carbon dioxide and hydrogen sulphide) can then be used to generate electricity, or even cleaned and compressed to form a fuel for motor cars.
