Why is it always found in places that accumulate sediment from above and often away from the edges of the tectonic plates?
Nobody would be surprised to not find oil and gas fields in the top 30% of Mount Everest.
If that is not a sedimentary basin from prehistoric times, I would agree.
What’s got people thinking about possible non biological sources of carbon energies is that there are methane and ethane clouds on places like Titan—one of jupiter’s moons.
The atmosphere of Titan is largely composed of nitrogen; minor components lead to the formation of methane and ethane clouds and nitrogen-rich organic smog. The climate—including wind and rain—creates surface features similar to those of Earth, such as dunes, rivers, lakes and seas (probably of liquid methane and ethane), and deltas, and is dominated by seasonal weather patterns as on Earth. With its liquids (both surface and subsurface) and robust nitrogen atmosphere, Titan’s methane cycle is viewed as an analogy to Earth’s water cycle, although at a much lower temperature.http://en.wikipedia.org/wiki/Titan_%28moon%29
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As well, there are artificial ways these days to make gasoline from CO2 — without using algae or bacteria,
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I have no strong opinion on this. For now I tend to believe that oil in the ground came from dead plants and animals of earlier epochs. but evidence suggests there’s more than one way to skin a cat and more than one way to make gasoline. whether that’s in fact what happened is another matter.