A research paper by USGS geochemist Leigh Price in 1999 estimated the total amount of oil contained in the Bakken shale ranged from 271 billion to 503 billion barrels, with a mean of 413 billion barrels -- original oil in place (OOIP). (200,000 square miles)With the deeper benches in the Three Forks formation, CLR says there could be 900 billion barrels of OOIP in the Bakken Pool.
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Ghawar is an oil field located in Al-Ahsa Governorate, Saudi Arabia. Measuring 280 by 30 km (170 by 19 mi), it is by far the largest conventional oil field in the world. When appraised in the 1970s, the field was assessed to have 170 billion barrels of original oil in place (OOIP). (3,230 square miles)"Drill, drill, drill is not an energy plan." -- President Barack Obama, February 22, 2012