Mineral Exploration is the official publication of the Association of Mineral Exploration British Columbia.
Issue link: http://digital.canadawide.com/i/370216
18 F A L L 2 0 1 4 I n the 1998 film Armageddon, a group of rugged drillers led by Bruce Willis' character is recruited to save the world by drilling into an Earth-bound asteroid to lower a nuclear device that will bust the rock in half. In a plot filled with slick futuristic spacecraft and technology, what of the drilling? Willis' crew uses regular drill rods and blowout protectors, and achieve a noth- ing-special shift of 180 feet – all pretty boring and standard stuff. Despite Hollywood's lack of imagina- tion for drilling technology, innovators are hard at work developing and refin- ing numerous advancements that stand to make drilling faster, safer and cheaper – and some technologies could be bona fide game-changers. The Australia-based Deep Explora- tion Technologies Cooperative Research Centre ( DET CRC) is at the forefront of mineral exploration drilling innovation where numerous technologies are being built and tested at a decommissioned open-pit mine test facility. In response to growing drilling costs but diminish- ing mineral deposit discovery rates, this research organization was established in 2010 and boasts $145 million in govern- ment and in-kind partner funding. Recent ly, a team of DET CRC researchers used carbon fibre drill rods in successfully completing an HQ-sized test hole to 100 metres. Although pri- marily designed to house behind-the-bit, real-time sensors of rocks, intersected, carbon fibre drill strings are being investigated – and at 30 per cent of the weight of industry-standard steel rods, these rods have an obvious edge in deep- drilling situations. But this technological leap also has significant upside for heli- copter-supported drilling programs of the type perfected in the remote moun- tainous regions of British Columbia and Yukon. For typical drill depths, lighter drill strings could be effectively deployed with much lighter drills, requiring smaller and lighter drill pads. Given the high cost of transporting equipment between drill sites, there is significant potential to drill more metres with fewer dollars when these drill rods become commercially available. The portable X-ray f luorescence ( XRF) analyzer has become as common on exploration sites as a Brunton com- pass, so it is no surprise that integration of these rapidly acquired geochemical data sets is extending to drilling plat- forms. Although the technology won't replace the eyes of a geologist anytime soon, researchers from the DET CRC, in collaboration with Geoscience Australia and the Geological Survey of Victoria, recently drilled a series of holes with real-time XRF and XRD data capture and management. Geochemical and mineralogical results were immediately available for interpretation through the web. This technology has the scope to advance rapidly, whereby hole status information such as drill hole deviation and drilling rate will be included with Beyond Hollywood's imagination THE LATEST DRILLING TECHNIQUES ARE ABOUT MORE THAN JUST GETTING ROCK IN THE BOX By Darcy Baker THE WIRELINE SYSTEM A DIFFERENCE-MAKER One of the major application breakthroughs in the diamond drilling industry was the development of the wireline system in 1958 by E.J. Longyear Company (now Boart Longyear Ltd.). The principal features of this system were adapted from the petroleum industry's application of the wireline methods for down- the-hole retrieval of drill core. The introduction of the wireline system revolutionized the diamond drilling industry by significantly increasing drilling productivity and performance by providing a procedure for retrieving drill core without having to trip all the drill rods from the drill hole for each run. Previously, with conventional standard drilling equipment, the entire string of drill rods had to be pulled from the hole to recover the drill core. This laborious procedure became very frustrating when core blockages occurred over very short intervals when drilling through highly fractured rock and fault zones. Drill rods are now only pulled for bit changes, unexpected down- the-hole problems and special procedures such as wedging. In addition to dramatically increasing drilling productivity, higher core recovery, less caving and core blocking, longer bit life and lower drilling costs were all made achievable by the wireline system. Wireline drilling was introduced in British Columbia in January 1963 when Canadian Longyear was contracted for a drilling program at the Endako molybdenum project. Subsequently, many exploration companies involved in the B.C. porphyry copper exploration rush and other exploration projects quickly adopted this new drilling technology to advance their projects. — Ed Kimura