System and Method to Measure or Generate an Electrical Field Downhole

摘要

The invention relates to measuring and generating electrical fields downhole. In one embodiment a system is provided that includes a first electrical conductor within a borehole and in electrical contact with the Earth. An amplifier is connected to the first electrical conductor and a second conductor completes an electrical circuit between the conductors such that the electrical field is oriented in a direction substantially orthogonal to the axis of the borehole.

主权项

1. A system for generation or measurement of an electrical field downhole comprising:
a first electrode within a borehole having an axis, the electrode in electrical contact with the Earth; an amplifier connected to the first electrode; a second electrode configured to complete an electrical circuit with the first electrode; and either:
a) at least a third electrode, with the second and third electrodes constituting counter electrodes spaced from each other and disposed outside the borehole, and an associated sensor, located external to the borehole, that measures an electrical field produced by the system in the Earth between the first electrode and each of the counter electrodes;b) an associated source that produces an electrical field in a direction substantially orthogonal to the axis of the borehole that is measured by the system and, wherein the source is located external of the borehole and the first electrode is configured to make electrical contact with the Earth via an operative capacitive coupling; orc) both a) and b).