“All oilfields are formed from sedimentary basins.”
“All sedimentary basins are form by sediments that flowed from higher elevations.”
How deep has oil been discovered? I had the impression oil has been discovered several miles down. Are we to think that 2 or 3 miles of rock sediments have been deposited atop the oil sediments? Even on a geologic timescale, that beggers belief.
Do you think oil creation could also be abiotic? The gaseous planets contain methane, so I wonder if oil might be found there as well?
All is in sedimentary basins. We have many sedimentary basins, oil producing and not, that are many miles deep.
1 inch per thousand years, for 400 million years is over six miles deep.
Thinking in geological time frames is not normal for those of us not in geology. If you ignore the oil part and just learn geology, the oil part is easier to then understand.
Methane exists in abiotic formation in planets without sufficient oxygen. In those locations, methane, ethane etc depending on the ratio of hydrogen and carbon, is the lowest energy state for those atoms to form into molecules after cooling from a big bang event.
But simple methane, ethane is a far cry from the Paraffins, Naphthenes, Aromatics, Asphaltics hydrcarbons found in crude oil, plus Sulfur, Nitrogen, some CO and/or CO2, iron, nickel, vanadium and salts. Each oil field has a different composition and oil in the same surface location will have quite different characteristics at different layers, each under its own cap rock that doesn’t allow it to migrate higher.
Also crude oil contains biotic markers like microfossils of Foraminifera and the like. More on that can be found:
http://www.ucmp.berkeley.edu/fosrec/ONeill.html