&lt;title&gt;Application of borehole radar to South Africa's ultradeep gold mining environment&lt;/title&gt;

Trickett, J.C.; Stevenson, Frederick; Vogt, D.; Mason, I. M.; Hargreaves, Jonathan; Eybers, H.; Fynn, R.; Meyering, M.

doi:10.1117/12.383497

Cited by 8 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…ADCs with a dynamic range of just 16 bits are still not commodity items at sampling rates above 10 MS/s. From Trickett et al (2000), it is known that a radar with a bandwidth of about 100MHz can provide the range required. For the development of the Aardwolf radar, the target bandwidth is 90 MHz, and the minimum acceptable bandwidth is 16 MHz.…”

Section: Technical Requirementsmentioning

confidence: 99%

A borehole radar system for South African gold and platinum mines

Vogt¹

2006

South African Journal of Geology

View full text Add to dashboard Cite

Borehole radar is an electromagnetic tool that can be applied to assist in the delineation of orebody geometry, ideally using routinely drilled cover and exploration boreholes. Successful trials of borehole radar for delineating reef horizons on South African gold and platinum mines have led to the development of a borehole radar system specifically designed for routine application in those environments. The radar design includes novel elements, including a receiver with instantaneous sampling down the borehole, and it is implemented in probes that can operate in 48 mm boreholes, with development planned for 38 mm boreholes. The radar is known as the Aardwolf BR40.The need for information about dislocations of 3 m to reefs determines the desirable radar resolution while available access geometry determines the range requirement. The electrical properties of typical gold and platinum rocks show that the range/resolution trade-off is feasible for the majority of economically important reef horizons. Boreholes drilled horizontally or upwards are accessed using a borehole crawler.Trials of the radar show that it meets its performance specification. The radar is robust enough for routine work underground and is easy to use. The borehole radar is a useful addition to the toolbox of the mining geoscientist because it can give information about the reef plane along a line, rather than the single point information about the reef given by a borehole.

show abstract

Section: Technical Requirementsmentioning

confidence: 99%

A borehole radar system for South African gold and platinum mines

Vogt¹

2006

South African Journal of Geology

View full text Add to dashboard Cite

show abstract

“…1992; Tillard 1994; Grasmueck 1996). Direct application in hard‐rock mining has been conducted for the past 30 years, but scientific publication of this effort is limited to the early work and current publications generally describe the use of borehole radar information (Cook 1973, 1975; Dolphin, Beatty and Tanzi 1978; Daniels 1988; Franké and Nobes 2000; Geophysical Survey Systems, Inc. 2000; Trickett et al . 2000).…”

Section: Introductionmentioning

confidence: 99%

“…However, applications of the technique in crystalline rocks have been primarily devoted to delineating cracks for engineering applications or nuclear waste storage facilities (Holloway 1992;Olsson et al 1992;Tillard 1994;Grasmueck 1996). Direct application in hard-rock mining has been conducted for the past 30 years, but scientific publication of this effort is limited to the early work and current publications generally describe the use of borehole radar information (Cook 1973(Cook , 1975Dolphin, Beatty and Tanzi 1978;Daniels 1988;Franke Â and Nobes 2000;Geophysical Survey Systems, Inc. 2000;Trickett et al 2000). Identification of mineralized zones, in granitic rocks for example, has been somewhat elusive (Lees 1998).…”

Section: Introductionmentioning

confidence: 99%

Successful application of ground‐penetrating radar in the exploration of gem tourmaline pegmatites of southern California

Patterson

Cook

2002

Geophysical Prospecting

View full text Add to dashboard Cite

Application of ground‐penetrating radar has been successful in delineating gem‐bearing zones in the Himalaya pegmatite mine of the Mesa Grande district of southern California. The high frequency of the electromagnetic signal allows features as small as a few centimetres to be resolved within 1–2 m of the surface of a mine wall. Careful initial set‐up consisted of: (i) selection of antennae with sufficiently high central frequencies; (ii) recording with a short time of scan to reduce end‐of‐scan noise levels; (iii) choosing appropriate colour schemes to highlight extreme amplitude variations. Operation during data collection consisted of pre‐painting marking points on the mine face and air launching the signal to reduce false anomalies caused by rocking of the antenna on the rough surfaces. Data processing using the Hilbert transform provided images of the cavity geometry that were then used by the blasting captain for accurate placement of explosives. The instantaneous frequency plot was found to be effective in distinguishing air‐filled from clay‐filled pockets, and the instantaneous phase plot was helpful in selecting potential targets where the amplitude was less than the maximum range. When carefully used in conjunction with good knowledge of the geological conditions, the method promises to provide an important tool for mapping internal structures of pegmatites, thus assisting future mining activities.

show abstract