•Increasing Production and Reducing Overall Drilling and Completion Costs
•Cost experts agree that horizontal wells have become a preferred method of recovering oil and gas from reservoirs in which these fluids occupy strata that are horizontal, or nearly so,
–they offer greater contact area with the productive layer than vertical wells
–While the cost factor for a horizontal well may be as much as two or three times that of a vertical well, the production factor can be enhanced as much as 15 or 20 times,
•Applications for horizontal wells include the exploitation of thin oil-rim reservoirs, avoidance of drawdown-related problems such as water/gas coning, and extension of wells by means of multiple drainholes.
•During the 1950s, the Soviet Union drilled 43 horizontal wells, a considerable effort with respect to the equipment available then.
•Following their foray into horizontal drilling, the Soviets concluded that while horizontal wells were technically feasible, they were economically disappointing or, in other words, not profitable.
–As a result, they abandoned the method.
•Unlike a directional well that is drilled to position a reservoir entry point, a horizontal well is commonly defined as any well in which the lower part of the wellbore parallels the pay zone.
•The angle of inclination used to drill the well does not have to reach 90°for the well to be considered a horizontal well.
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