Derb,

The US Geological Survey issued a new report on the Bakken field only about a month ago. They find that there’s up to 4.3 billion barrels of oil there that is “technically recoverable,” i.e. we could get it out now. That’s the equivalent of about five years’ import from the Persian Gulf at current rates, so it’d be useful but no paradigm-breaker. We may be able to get more out in the future as technologies improve, of course. The real question, however, is whether we’d ever be allowed to get it out.

Meanwhile, the Tupi oil field off Brazil is likely to hold between 5 and 8 billion barrels, although some people are saying up to 30 billion.