Abstract: A magnetic resonance measurement apparatus that is subject to relative motion between the apparatus and a specimen along a path includes a magnet, antennae and a circuit. The magnet polarizes the specimen, and the antennae are spatially distributed along the path. The circuit uses the antennae to perform magnetic resonance measurements and use the spatial distribution of the antennae to establish different polarization times for the magnetic resonance measurements.

Abstract: A method for measuring multiphase flows in a conduit using series of microwave antennae arranged around the circumference of the conduit so as to transmit microwave energy into, or detect propagated microwave energy in the conduit, the method including the steps of: transmitting microwave energy from each antenna in turn while detecting microwave energy at the non-transmitting antenna and integrating the results from all antennae so as to characterize the flow in the conduit. Apparatus for performing the method includes means for exciting each antenna in turn to transmit microwave energy into the pipe and means for detecting microwave energy at the non-transmitting antennae, and means for integrating the results from all transmitters to characterize the flow in the conduit.

Abstract: A two-dimensional array of slot antennas which can provide two-dimensional quantitative dielectric and conductivity images of formations in the region surrounding an earth borehole. The antennas are mounted in a wall-engaging member of a logging device that is moveable through the borehole. Selected ones of the antennas are energized at given times to transmit electromagnetic energy into the formations, the electromagnetic energy being received at other antennas for processing to obtain formation properties.

Abstract: A spontaneous potential (SP) sub is interconnected between two metallic housings of a wellbore apparatus and is lowered into a wellbore. A spontaneous potential (SP) of an earth formation trasversed by the wellbore is measured by the SP sub, and a log is generated from the sub which is representative of the spontaneous potential of the formation, the log being substantially free of a special type of distortion which typified the prior art SP measurements taken by prior art SP measurement apparatus. The SP sub includes a measurement electrode, monitoring electrodes placed on both sides of the measurement electrode, a bucking electrode placed on both sides of the monitoring electrodes, current driving circuitry connected to the bucking electrodes, and receiving circuitry connected to the monitoring electrodes. The current driving circuitry delivers a current of sufficient magnitude to each bucking electrode such that the voltage potential between the monitoring electrodes is approximately equal to zero.

Abstract: A form of the disclosure is directed to determining properties of formations surrounding an earth borehole having a standoff layer. A method is disclosed for determining the conductivity and permittivity of the standoff layer and the conductivity and permittivity of the formations adjacent the standoff layer. A further form of the disclosure is directed to an electromagnetic logging apparatus having transmitting and receiving antennas in RTTR, RRTTRR or TTRRTT arrangements.