Assessment of Undiscovered Oil Resources in the Devonian-Mississippian Bakken Formation, Williston Basin Province, Montana and North Dakota, 2008 Click on the pictures for larger view.
Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean undiscovered volumes of 3.65 billion barrels of oil, 1.85 trillion cubic feet of associated/dissolved natural gas, and 148 million barrels of natural gas liquids in the Bakken Formation of the Williston Basin Province, Montana and North Dakota.
This is a lower figure than I had guessed. However, it is 24 times more than the 1995 estimate of 150 million barrels and 6 times more recent quotes of 600 million barrels. It increases the US assessment of October 2007 from 42 billion barrels to 45 billion barrels a 6.7% increase. This is a probable [50% probable] reserves number as the old proven [90% likely] reserve number was 21 billion barrels Proven reserves increases by almost 3 billion barrels. The 95% figure was 3063 million barrels of oil. The old proven reserves was 150 million barrels. So the US proven reserves number goes up to 24 billion barrels a 15% increase. Adding almost 2 years to the 12 year life of US reserves based on proven reserve calculations.
As technology improves I would expect the recovery rates to increase.
Here is the fact sheet
The assessment methodology of the USGS
USGS 1995 study and current decline rates
Estimates of bakken oil size and timing
Multistage fracturing horizontal drilling technique
Here is more details on how horizontal drilling and fracturing work
Bakken oil not fully valued
Bakken oil is highly profitable
A Saudi Arabia of oil in Bakken and Toquay formations in the USA and Canada
Other methods of resurrecting old oil wells. 67% of US oil is still in old wells and needs new technology to help recover it.
More bakken news from Google news