Formation resistivity measurements using multiple controlled modes

Patent metadata

Field	Value
Publication number	US-8965702-B2
Application number	US-201213359563-A
Country	US
Kind code	B2
Filing date	Jan 27, 2012
Priority date	Mar 31, 2011
Publication date	Feb 24, 2015
Grant date	Feb 24, 2015

Abstract

Disclosed is an apparatus for estimating a property of an earth formation penetrated by a borehole. The apparatus includes a plurality of electrodes disposed downhole and configured to inject an electrical current into the earth formation using an applied voltage and/or measure electrical current resulting from an injection of the electrical current. The apparatus also includes a processor configured to perform a series of formation measurements that include injecting current into the earth formation using a unique subset of electrodes in the plurality of electrodes and measuring current in the earth formation using one or more electrodes not used for the current injecting. The processer sums the measured currents for the electrodes wherein the sum of electrical currents for at least one electrode that measured electrical current is substantially in phase with the applied voltage; and uses the sum of in phase currents to estimate the property.

First claim

What is claimed:

1. An apparatus for estimating a property of an earth formation penetrated by a borehole, the apparatus comprising:
a carrier configured to be conveyed through the borehole;
a plurality of electrodes disposed at the carrier and configured to inject an electrical current into the earth formation using an applied voltage and/or measure electrical current resulting from an injection of the electrical current; and
a processor configured to:
perform a series of fo…

Assignees

• Tabarovsky Leonty A
• Forgang Stanislav W
• Baker Hughes Inc

Inventors

• Tabarovsky Leonty A
• Forgang Stanislav W

Classifications

• G01V3/26 Primary

  Physics · mapped topic