Dual Induction-Conductivity Logging - Overview Application: Induction-conductivity logging involves the measurement of induced electromagnetic fields in the rock and resulting eddy currents. Changes in the rock’s electrical properties can be due to the clay...
Probe calibration, normalisation and verification – what is the difference? Calibrated data, this is often stipulated by a client in a contract but the calibration is commonly misunderstood. Calibration A definition of calibration is: A set of operations which...
A geophysical logging contractor is a small part of an exploration or mining development team. The team would likely include a drilling contractor(s), rig geologists, staff geologists, fieldies, logistics, and camp logistics. But if you are drilling deep boreholes or...
I attended a presentation by DET CRC at the Australian Society of Exploration Geophysicists concerning the principles of the project and a current status. The talk outlined the guiding principles of the program: The need to drill more boreholes in areas covered by...
The Australian Society of Exploration Geophysicists event was held at the Perth Convention Centre on the Saturday before the main conference. There were over 40 attendees who were treated to a range of presentations from major geophysical logging contractors in WA...
The fullwave sonic probe measures sonic waves (via pressure pulses) between a transmitter and a series of receivers – all at fixed distances in the probe. Velocity or transit time of the sound wave is a very useful parameter for engineering parameters such as rock...
Borehole imaging probes are now a common service provided in boreholes drilled for mineral exploration, geotechnical investigations and groundwater programs. The major mineral borehole imaging methods are: Acoustic imaging: requires a fluid filled borehole Optical...
Full image coverage of a borehole wall in true colour – the optical scanner probe The optical scanner uses a high resolution digital camera together with magnetometers and accelerometers to provide an orientated true colour image of the borehole wall. Principal...
Ever wanted accurate compressional and shear wave arrival times in uncompacted near surface sediments? The borehole P-S seismic suspension logging probe has been designed for this purpose and can provide these measurements from inside PVC casing. By themselves, the...
Full image coverage of a borehole wall – the acoustic scanner probe. The acoustic scanner, also known as the acoustic televiewer, uses high frequency sound wave echoes together with magnetometers and accelerometers to provide an orientated travel time and amplitude...