Eugene Island is an oil field in the gulf of mexico discovered in 1971 with an API between 23 and 35 degrees. The field has an expectional structure with one of the largest faults (planar rock fractures, which show evidence of relative movement). This large fault (the red fault) allowed the reservoir to fill rather quickly from the source rock after pressure dropped 24 years from initial production. This exceptional structure caused a significant increase in reserves by reserve growth.

Sounds familiar. Would this be the field that often gets cited by the advocates of abiotic oil?

While I don't hold much stock in the abiotic oil theory, I WAS under the impression that the depths at which the new oil is being pumped into the reservoir was from a location that was outside the 'magic window' where oil can form and not be broken down. Could the magic window be far larger then we believe?

Absent fluids like water or lava, heat diffuses slowly through substances like rock.  ISTR speculation that those deposits may not have been at their current depth for very long (in geologic terms).  If we had come along in a few million more years there may have only been gas there.

i have heard that speculation also (rapid subsidence) but what do we really know about the fluids produced from this reservoir? there is a fine line between a volitile oil reservoir and a retrograde condensate (gas) reservoir . now i know chevron's scientists know what they are doing but the difference is not always obvious. east anschutz ranch field in se wyoming is a fine example . i dont know if they have ever resolved the issue .

Who knows the reality of the location of the magic window, or if its just a bad hypothesis of the geochemists ? Certainly Jack 2's oil productive zones in the Wilcox and Eugene Island's recharge zone that is thought to be Cretaceous argue that the current hypothesis is incorrect.
The first time I heard the abiotic oil theory was from a petroleum engineer and drilling company owner named Carnes Weaver over 20 years ago in Houston. He was a great old guy, now dead at least 15 years. He presented me the theory not because he believed it, but rather as a thought stimulating exercise. His point, and its definitely a fact, is that oil is where you find it. He thought any place with reservoir rock was potentially productive. His main example was the field in the Panhandle of Texas that produces 25% helium in natural gas. Helium is not reactive with many other chemicals and has a volcanic origin.
So Hothgar, that's a great question, and I don't know if there is an answer to the oil window theory and its place in opposition to Abioticists

Not the threadjack, but that was by far the best Hothgor post I have read yet.

Actually, the SEC restrictions on speculations regarding oil reserves is a form of abiotic oil formation. Clearly the SEC is not an organic entity and they can force reserves to go up and down due to the whims of the current regulators.

For every Eugene Island that we deal with, we have an army of regulators and collusions amongst and within the oil companies to make vast amounts of reserve oil to appear or disappear at a moment's notice. Now that's what I call abiotic oil!