ELECTROMAGNETIC LOGGING APPARATUS Russian patent published in 2013 - IPC G01V3/30 

FIELD: physics.

SUBSTANCE: apparatus has a logging tool which moves on a well bore, an electromagnetic probe 1, having a logging probe shoe 2, which is mounted on the logging tool, configured to engage with the well bore which engages with the surface of the shoe, at least one pair of transmitting antennae T_xA, T_xB, mounted on the engaging surface of the shoe, and a plurality of spaced receiving antennae R_xA, R_xB, mounted on the engaging surface of the shoe, lying at a distance from the pair of transmitting antennae T_xA, T_xB. All antennae T_xA, T_xB, R_xA, R_xB are open end antennae which form a substantially clean electric dipole which is normal to the surface of the shoe of the logging probe.

EFFECT: high accuracy of measuring formation properties in conditions where there is a film of drilling mud on the wall of the well bore.

12 cl, 12 dwg