Depth and Geographical Reference Systems
The trajectory of a deviated well must be carefully planned so that the most efficient trajectory is used to drill between the rig and the target location and ensure that the well is drilled for the least amount of money possible. Here we shall understand what is the Depth and Geographical Reference Systems

When planning, and subsequently drilling the well, the position of all points along the wellpath and therefore the trajectory of the well must be considered in three dimensions.
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