July 2008

It's not the hole; it's the direction

The future of oil wells is horizontal. That would be drilling from side to side rather than straight down.

We have known for years that drilling in a horizontal fashion is possible and beneficial in the exploration for and extraction of oil. The lack of investment in this technology and other smart technologies by nationalized oil companies may be a culprit.

MIT's Technology Review reported even with record-high oil prices, about two-thirds of the oil in known oil fields stays behind in the ground. That is because existing technologies that could extract far more oil, as much as about 75% of the oil in some oil fields, are not being widely used.

Several well-established technologies, including "smart oil fields," exist that could significantly boost the supply of petroleum from oil reservoirs. However, a lack of investment in such technologies, particularly by the national oil companies that control the vast majority of the world's oil reserves, is holding back implementation.

In most oil reservoirs, the oil resides in porous rock in geologic layers that are tens of meters thick but stretch for miles. A conventional oil well is a vertical shaft, so it is in contact with only a narrow cross section of the reservoir.

Such a well depends on oil percolating through microscopic pores over long distances. That can slow production, and often oil cannot get through the irregular geometry of the oil field.

For 15 to 20 years, however, it has been possible to drill horizontal wells. These follow along the length of an oil field, so the well is in contact with oil for miles, rather than for just several meters.

Furthermore, advanced imaging technologies and new drilling rigs have made it possible in recent years to drill to an accuracy of one or two meters, Sears said. The increased precision in drilling allows oil companies to stay close to the top of the reservoir, where the oil is, and away from the water that can exist in the reservoir.