There was a test well. That makes the estimate 10 gb better than a SWAG.

one test well 10 gb ??????? roflamo

I also understood that there had been one test well drilled in ANWR, but that the findings were not public.

I did a fairly intensive search of the EIA, though, and could not find any reference to the test well. Instead estimates of oil resources seemed to be based on comparisions of other areas with similar geographical structures.

Does anyone have any more solid data on what we actually know about potential resources in ANWR?

the 10 gb figure is apparently the mid range of usgs estimates, based on very limited information, making lots of assumptions and applying monte carlo simulation.
when i first started learning fortran* the prof had a saying "gigo" (garbage in garbage out)

* that was back in the days when programing was done on punch cards (shortly after we graduated from basic programing - the programs were saved on tickertape)

Here are a couple of links on KIC-1 'The only test well drilled in ANWR' with its results still held confidential by Chevron.

http://www.gasandoil.com/goc/company/cnn11977.htm
http://anwrnews.blogspot.com/2005/04/aint-it-kic-story-of-anwrs-only-wel...

Like I said, SWAG, unless somebody has news of a more recent, and public, exploratory effort.