Unlock smarter decisions with precision borehole imaging
Driven by an increased geotechnical demand for the precise understanding of subsurface geological conditions, the use of borehole televiewer imaging has experienced continued growth in recent years.
Many drilling programs for mine geotechnical/geological applications, exploration, hydrogeology and civil infrastructure projects are benefiting from the capabilities delivered by borehole imaging data. This is particularly evident in the interpretation of a borehole structure, which provides more confidence and input into geological models. With minimal additional costs per meter given the expense of a drilling program, running the televiewer offers a complete picture downhole and removes core logging uncertainty.
The right televiewer selection is critical for successful project outcomes, but typically projects benefit from both tools where hole conditions permit.
Televiewers come in two model types — acoustic televiewer logs (ATV) and optical televiewer logs (OTV).
ATV use ultrasonic pulses to create continuous high-resolution, precise depth, and ORIENTED images of the borehole wall, which are run in fluid-filled boreholes. The tool emits ultrasonic signals that reflect off the borehole wall, and the reflected signals are recorded to produce an image. This method is excellent for identifying fractures, faults, shear and bedding planes, broken zones, lithological contacts, breakouts, other structural features and their aperture within the borehole.
OTV, on the other hand, use a high-resolution digital camera array to capture continuous, precise depth, ORIENTED images of the borehole wall. These logs are best suited for dry or clear water-filled boreholes. They provide detailed colour images that are useful for lithological characterisation, identifying fractures, faults, shear and bedding planes, broken zones, lithological contacts, breakouts and other structural and mineralogical features, and even supplementing core, known as digital or virtual core.
The lifecycle of projects also benefit from televiewers’ multidisciplinary uses of data. At every stage, geologists, geotechnical engineers, hydrogeologists and geophysical teams can interpret data with a focus to a specific need. Tying in other drilling, geological, laboratory, geophysical data and core photos allows for a detailed interpretation and decision making capability.
Advanced Logic Technology (ALT) has been at the forefront of borehole logging system technology since its inception. Coupled with industry-leading borehole data processing and interpretation software WellCADTM, the company continues to develop both hardware and software products.
WellCADTM has been integral in thousands of projects globally for the successful interpretation of televiewer data with its image interpretation workspace. In mid-2025, a new geomechanical module for WellCADTM will be released to further benefit users with new and improved features that enables advanced data for more informed decision making.
Ultimately, the applications of televiewers for any drilling project are about reliable and accurate structural data from within the borehole to minimise risk and unlock smarter decisions. Improved rock mass characterisation, statistics and increased confidence in models, will reduce costly mistakes due to a lack of high-quality data.
With an experienced team in Australia, Geosensor Wireline offers a range of options, including systems for portable-shallow projects or truck mounted 2000m deep units, as well as surface and underground capabilities, sales, rentals, training, technical advice, data processing, field services and more.