BILDEDANNING I OLJEBASERT SLAM VED Å SYNKRONISERE FASENE I STRØMMER INJISERT I EN FORMASJON

Disclosed is an apparatus for estimating a property of an earth formation penetrated by a borehole. The apparatus includes a carrier configured to be conveyed through the borehole. A first transmitter electrode and a second transmitter electrode are disposed at the carrier and configured to inject an electrical current into the earth formation. A first measurement electrode and a second measurement electrode are disposed at the carrier and configured to measure the electrical current to estimate the property of the earth formation. A first bucker amplifier is coupled to the first measurement electrode and a second bucker amplifier is coupled to the second measurement electrode, wherein the first and second bucker amplifiers are configured to equalize electrical potentials of areas in front of the first and second measurement electrodes.