COMBINED ELECTRIC FIELD TELEMETRY AND FORMATION EVALUATION METHOD AND APPARATUS

摘要

An apparatus for borehole electric-field telemetry that comprises asource of modulated voltage or current, at least one axially non-conductivecollarconnected between pipe sections in a pipe string, and a system of insulatedwirelinecomponents providing electrical connections, insulated from drilling fluids,betweenthe ends of the one or more aforementioned insulated collars in the pipestring, totransmit the voltage or current.