Is The "bakken" basin (Petroleum) All that big?

Lately, the penny stock crowd has been toudting this new area for oil drilling-the "bakken’ basin of N. Dakota. My question: if this deposit is so huge (200 billion barrels0, then why aren’t the major oil companies drilling there? Sounds like a fraud about to happen!

I hadn’t heard of this, so I spent a couple of minutes on google. What it basically looks like is that many people have tried to drill there, but the oil is extremely difficult to get out of the ground. The wikipedia page on the Bakken Formation says some estimates about how much oil they will ever get out of there are as low as 1 percent. There seems to be a lot of new drilling, but I imagine investing in these companies would carry a very high amount of risk.

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