SURFACE EXCITATION RANGING METHODS AND SYSTEMS EMPLOYING A GROUND WELL AND A SUPPLEMENTAL GROUNDING ARRANGEMENT

摘要

A surface excitation ranging method includes selecting a first well with a metal casing as a target well and selecting a second well with a metal casing as a ground well. The method also includes installing a supplemental grounding arrangement for a power supply located at earth's surface, wherein the ground well and the supplemental grounding arrangement fulfill an impedance criteria or ranging performance criteria. The method also includes conveying an electrical current output from the power supply along the target well. The method also includes sensing electromagnetic (EM) fields emitted from the target well due to the electrical current. The method also includes using distance or direction information obtained from the sensed EM fields to guide drilling of a new well relative to the target well.