Bakken Oil Field... Is it positive or negative in the economy if it were to be produced? Help with macroeco!!?

Sooo, I'm helping my sister out with a paper she's writing for her macroeconomics cl... It is to be about “How not using our Oil Reserves Affect the Economy.” And how it negatively affects our economy by not using it. I'm not sure where she learned about the oil reserves in America, but she stated that none were being used for consumption by the U.S. and none have been drilled into. She said they were being "reserved." I've been reading about these oil reserves for hours, and from what I've read they are all producing oil except the ANWR. And after reading about ANWR I don't see how that would benefit the economy, mainly because it's the little bit of untouched wilderness left in America..also it'll only last 50 years or so with the amount of US yearly consumption... Nor do I see how Bakken would benefit the economy, because since it's continuous, it's more expensive to extract... I've read wiki to FAQ at http://www.usgs.gov/faq, and still can't agree with that benefiting the economy. USGS can't seem to answer any of those questions about Bakken IMO but just deter one from anything close to the answer... I don't understand how they estimate Bakken to hold 500 billion barrels of oil when they say 4 billion is retrievable. And the 148 million they have produced, was it consumed by the US? If so, did it positively affect the economy? If we didn't consume it did we export it? I'm just soooooooooooo confused!!! Please, can somebody who knows facts not neccessarily copied from Wiki, but understandable explanations please help me. I'm close to just changing the topic, but I have no idea what else to change the topic to, esp if she wants to write about the oil reserves... It just seems that if I am going to write about our oil, it won't be the way she wants it.