If you're interested in the historical process, personally I like the videos of PBS Eons a lot:
They mention certain bacteria not being present to breakdown the plant matter of that special tree, but what about fungus, I would think fungus has been around a pretty long time. There's something very hand-wavy and too tidy about it all. I guess one thing is known is that these are carbon based materials and where does carbon primarily come from and how did it get way down in the bottom layers of the earth is a big question. I think today we'd identify the atmosphere, but it would be surprising if it was the other way around, if carbon mostly came from the earth and got released up as CO2 somehow. But CO2 is very stable, I think we'd expect the dominant source of an element to be all bound up in its most stable forms.
I'm curious too how deep down do oil wells go. This hit has some fascinating real world depths apparently. Hydraulic fracturing reaches depths ranging from 5,000 feet to 20,000 feet. https://www.petro-online.com/news/fuel-for-thought/13/breaki....
I'm curious next how much oil can be extracted from a well and how we could back track to that being some percentage of some originating mass and if the two things match up to some realistic numbers with our experience for how much mass one finds in a forest today, etc.
https://jgi.doe.gov/news_12_06_28/
> The comparative analyses suggested that around 290 million years ago, right at the end of the Carboniferous period, a white rot fungal ancestor with the capacity to break down lignin appeared. Prior to that ancestor, fungi did not have that ability and thus the lignin in plant matter was not degraded, allowing these lignin-rich residues to build up in soil over time.
> Once you have white rot you can break down lignin, the major precursor of coal.
I'm curious there how is it know that lignin is the precursor to coal.
What is coal anyways, is there a molecular structure to it. Ha, what a cool hit for that search, a rock, who'd have thought. I never heard of a maceral before.
> Coal is a sedimentary rock that is composed principally of two basic classes of materials: inorganic crystalline minerals and organic carbonaceous macerals. The macerals form the combustible part of the coal and are, in turn, divided into three maceral groups—vitrinite, exinite, and inertinite. https://www.sciencedirect.com/science/article/pii/B978012150...