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Step 1
Today as oil and gas deposits become harder to find and harder to get to there is a relatively new technology called horizontal drilling or directional drilling that allows oil companies to drill to reach a specific target that may be located some distance out from an offshore platform or under a city or other area where vertical drilling is impossible. In addition it enables oil companies to drill sideways across a bed of oil or gas bearing rock to allow more of the gas or liquid to be extracted by exposing more surface area.
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Step 2
The way horizontal drilling works is through the use of a device called a mud motor which is turned by the force of drilling fluid being pumped down the drill pipe. Because the motor can do the turning of the drill bit the drill pipe itself does not have to move. If a bend is built into the motor, say perhaps 3 degrees and the motor is turned in the direction of that bend the driller can let the motor and bit churn away in that direction. Bend your index finger and imagine the process, only hundreds of feet underground at the end of many lengths of pipe.
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Step 3
Another part of the system that makes horizontal drilling possible is a sensor called a MWD or LWD device. MWD stands for measure while drilling and LWD stands for Logging While Drilling. Either type of sensor can tell the driller at the surface which way the bend in the motor is pointed and which way the hole he is drilling is going. A series of measurements is taken with the MWD - LWD, which contains a sophisticated electronic compass and inclinometer which measures both direction and angle. The driller can use these measurements, which are displayed on a monitor at the surface, to tell him when the well bore or hole has reached horizontal or is going in the direction and angle that is desired.
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Step 4
The process of horizontal or directional drilling has opened up new gas frontiers inside the US such as the Marcellus Formation under New York, Appalachia and Pennsylvania, the Bakken Formation of North Dakota and the Barnett Shale of North Texas. Before horizontal drilling these dense shale rock formations did not produce enough gas or oil from a vertical hole but when more surface area is exposed production can be economically feasible.
