HIGH RESOLUTION ARRAY INDUCTION TOOL

摘要

A coil array for high resolution logging (Figure 3), comprises a transmitter (T), a first receiver set positioned at a distance from the transmitter (UR) , and a second receiver set positioned at a second distance from the transmitt er (LR), and a method for deriving a conductivity log from at least one inducti on well log that comprises a plurality of depth samples (Figure 4), comprising the steps of raising each depth sample of the conductivity signal to several predetermined powers to generate a plurality of powers of conductivity, convolving in depth the powers of conductivity with a plurality of filters, and summing the results of all the convolutions to produce a conductivity lo g that is free from the effects of adjacent beds and the nonlinear effects of true conductivity. The apparatus for measuring the resistivity, (figure 2), of an earth formation penetrated by a borehole, comprising at least one transmitter energized by a time varying periodic voltage, one set of receive rs generating a receiver voltage, with an analog to digital converter that periodically samples the receiver voltage at a predetermined sampling rate a nd outputs a digitized voltage signal, (Figure 2), and a computer processor tha t receives the digitized voltage signal, with a set of N accumulators that collates andaverages successive sets of N samples from the A-D converters an d outputs a set of N averages.