The dual induction probe provides conductivity logs with deep and medium depths of investigation to profile borehole fluid invasion into the formation. The tool uses an ‘array’ technique where multiple sets of in-phase and out-of-phase receiver responses are processed and summed to emulated the vertical and radial responses of classic 6FF40 ILD and ILM logs. The tool may be combined with other measurements and is run at the base of the stack. The probe includes a fast-reponse platinum resistance thermometer for measurement of external borehole temperature.
PRINCIPLE OF MEASUREMENT:
An oscillating high-frequency magnetic field created by a transmitter coil within the probe induces an alternating electrical current within the surrounding conductive formation. This current, in turn, induces voltages within multiple receiver coils in the probe proportional to formation conductivity. The transmitter-receiver spacings determine the depth of investigation of the measurements.
FEATURES
Multiple coil ‘array’ measurement using computer processing to synthesize tool responses. Raw data is also stored for post-log processing
Internal temperature compensation for low drift
Oil filled and pressure balanced mandrel
Fully digital telemetry combines with density, neutron and other logging probes
High resolution measurement. Maximum data sampling rate is 1cm (0.4”)
Includes external temperature measurement
MEASUREMENTS
Deep conductivity (ILD)
Medium conductivity (ILM)
Raw conductivity channels
Temperature and differential temperature
APPLICATIONS
Hydrocarbon saturation
Porosity
Lithology ( in conjunction with other logs)
Correlation between wells
OPERATING
CONDITIONS
Borehole type
Borehole type: 4” to 12” mud or air--filled openhole
SPECIFICATIONS
Diameter
63mm (2.5")
Length
4.13m (163")
Weight
28kg (62lbs)
Max. temperature
125ºC
Max. pressure
86MPa (12500psi)
Resistivity range
0 to 200ohm-m
(Qualitative indication up to 2000ohm-m)
