As of the end of 2002, a total of 190x109 barrels of crude oil had been produced in the US. When the future resource of 134(105+ 29)x109 barrels is included, a value of 324 x109 barrels is obtained for Q The US is now consuming about 6.7x109 barrels per year of petroleum, so at that rate the oil resource would be completely exhausted in 20 years. ?? After a well stops producing by normal exaction processes, about 70% of the petroleum is left behind the ground Secondary recovery involves pumping either water or gas into the surrounding area to force more oil toward the well (another 15%) Tertiary techniques are used to overcome the two effects that lock the oil in interfacial tension and viscosity Viscosity: CO2 or steam injection Surface tension: detergents injection Enhanced recovery is expensive and can have unfortunate environmental consequencesAs of the end of 2002, a total of 190x109 barrels of crude oil had been produced in the US. When the future resource of 134 (105+29) x109 barrels is included, a value of 324 x109 barrels is obtained for Q∞ . The US is now consuming about 6.7x109 barrels per year of petroleum, so at that rate the oil resource would be completely exhausted in 20 years. ??? • After a well stops producing by normal exaction processes, about 70% of the petroleum is left behind the ground. • Secondary recovery involves pumping either water or gas into the surrounding area to force more oil toward the well (another 15%). • Tertiary techniques are used to overcome the two effects that lock the oil in: interfacial tension and viscosity. Viscosity: CO2 or steam injection Surface tension: detergents injection • Enhanced recovery is expensive and can have unfortunate environmental consequences