Planning directional wells through a high-density cluster of existing wells

A method is described for determining the optimum well path through a high density cluster of existing wells by considering the close proximity of the other wells. The planning starts from the investigation of simple two-dimensional well paths, then turns to the three-dimensional well path if there is not a safe two-dimensional path available. While planning, the modification of the proposed well path can be made if necessary within the constraints of dog-leg severity, hole inclination, and the proximity of neighbouring wells. An example using North Sea data is also presented.