Directional drilling (or slant drilling) is the practice of drilling non-vertical bores. It can be broken down into four main groups: oilfield directional drilling, utility installation directional drilling, directional boring (horizontal directional drilling - HDD), and surface in seam (SIS), which horizontally intersects a vertical bore target to extract coal bed methane.
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In this Dossier
Slant-drilling in the context of Rumaila oil field
The Rumaila oil field is a super-giant oil field located in southern Iraq, approximately 50km to the south west of Basra City. Discovered in 1953 by the Basrah Petroleum Company (BPC), an associate company of the Iraq Petroleum Company (IPC), the field is estimated to contain 17 billion barrels, which accounts for 12% of Iraq's oil reserves, estimated at 143 billion barrels. Rumaila is said to be the largest oilfield ever discovered in Iraq and one of the three largest oilfields in the world.
Under Abdul-Karim Qasim, the oilfield was nationalised by the Iraqi government by Public Law No. 80 on 11 December 1961. Since then, this massive oil field has remained under Iraqi control. The assets and rights of IPC were nationalized by Saddam Hussein in 1972, and those of BPC in 1975. The dispute between Iraq and Kuwait over alleged slant-drilling in the field was one of the reasons for Iraq's invasion of Kuwait in 1990.
View the full Wikipedia page for Rumaila oil field