Would be interesting to see how they compensated for the fact that the air trapped in the Lava was superhot and expanded as well as stripped of most of it’s hydrogen and oxygen.
The dirt people probably used recent lava as a control.
“Would be interesting to see how they compensated for the fact that the air trapped in the Lava was superhot and expanded as well as stripped of most of it’s hydrogen and oxygen.”
There was virtually no Oxygen in the Earth’s atmosphere until about that time. The Hydrogen and Ammonia that dominated the composition of the Earth’s first atmosphere was largely lost during and in the aftermath of the collision that created the Moon/Luna and finalized the Earth’s size and composition. This resulted in the Earth’s second atmosphere that was upwards of 100 times thicker and more massive than today’s atmosphere and was composed of greater than about 95 to 98 percent Carbon dioxide. This was an atmosphere that would have crushed today’s macro organisms. The microorganisms in that period of time were anaerobic, meaning they would have been poisoned by the presence of Oxygen in the atmosphere and hydrosphere. It was not until about the time of these rocks 2.7 billion years ago that aerobic, meaning Oxygen loving, life forms developed as life removed Carbon dioxide from the Earth’s atmosphere, metabolized the carbon into organic compounds, and released Oxygen into the atmosphere and hydrosphere. This massive release of Oxygen interacted with the massive quantities of iron in the lithosphere and the hydrosphere to produce massive quantities of Iron oxide (rust). This huge amount of Iron oxide rust produced the planet wide red rock layers until there was no longer enough iron left to react to the available Oxygen, which then allowed the Oxygen levels to increase beyond the previous micro trace amounts to become a substantial percentage of the Earth’s third atmosphere then composed for the most part of Nitrogen and Oxygen. The Carbon dioxide that previously had been almost the entire composition of Earth’s atmosphere when it was upwards of 100 times greater mass than today was almost entirely removed from the atmosphere by life, leaving only trace amounts and an atmosphere less than about 1 percent its previous mass and atmospheric pressure.
Hydrogen as an appreciable percentage of the Earth’s atmosphere had long ago been lost from the atmosphere, and Oxygen as more than a trace amount of the atmosphere was just beginning to accumulate in the Earth’s atmosphere for the first time as the Great Rusting event reached its peak activity and Oxygen was finally able to remain free in the Earth’s atmosphere.
One of the remaining big unknowns would be the effect of the rock on the gas over billions of years, especially given the fact that the rock has probably been compressed and heated repeatedly.
There's a similar issue with CO2 samples from gas bubbles in ice cores, since CO2 readily dissolves in water.