Trends & Developments
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Exploration TRENDS & DEVELOPMENTS March 2012 Complimentary PM no. 40069240 airborNe geophysical surveys for miNiNg exploratioN electromagNetics: Helicopter-borne Frequency-domain EM • Time-domain EM • VLF-EM magNetics & gradiometry: Fixed-wing or Helicopter-borne radiometrics: Fixed-wing or Helicopter-borne coming soon - gravex: A gravity sensing system providing high resolution gravity and gradient data New dimeNsioNs iN exploratioN To explore more about our groundbreaking services, visit www.mcpharinternational.com or e-mail us at [email protected] McPhar_Admat_FP_TNME_Jan12_x1a.indd 1 19/01/12 12:17 PM Exploration KEGS’ sixth year as patron of TRENDS & DEVELOPMENTS Exploration Trends & Developments is an annual publication prepared by Patrick G. Killeen By Patrick G. Killeen PhD, Geophysical Consultant RR # 1, 9759 Highway 509 and retired Research Scientist, Geological Survey of Ompah, ON Canada, Ottawa 2011 Canada K0H 2J0 Phone: (613) 479-2478 The Trends review Sponsor’s Box below. This marks the 20th E-mail: [email protected] originated with the year it has been written by Patrick Killeen, Published in co-operation with Geological Survey of originally as a research scientist at the The Northern Miner 12 Concorde Place, Suite 800 Canada (GSC), where, GSC, and since 2007 through KEGS. Toronto, Ont. for over 45 years, GSC scien- Founded in 1953, KEGS has the M3C 4J2 tists have prepared an unbiased stated purpose according to the Phone: (416) 510-6768 annual publication on trends constitution: “... to promote the Fax: (416) 510-5138 and new developments in geo- science of geophysics especially E-mail: [email protected] physical exploration for miner- as it is applied to the explora- Editor: als. The Canadian Exploration tion for minerals other than oil; Alisha Hiyate Geophysical Society (KEGS) to foster the common scientific Writer: first became the primary “pa- interests of geophysicists; to Patrick G. Killeen tron” of the annual review of maintain a high professional Art Director: Mineral Exploration Trends & Develop- standing among its members; and to pro- Mark Ryan ments in 2007. This year, KEGS support mote fellowship and co-operation among Production Manager: came from the companies listed in the persons interested in these problems.” Tracey Hanson Advertising Sales: Brian Warriner SPONSORED BY Joe Crofts Teri Richardson Platinum Level Silver Level Bronze Level Publisher: (up to $1,500): (up to $500): (up to $250): Doug Donnelly Condor Consulting Inc. IFG Corp. Geonics Ltd. Printed in Canada. Abitibi Geophysics All rights reserved. Mount Sopris RMS Instruments Instrument Co. The contents of this publication Gold Level Sander Geophysics Ltd. may only be reproduced with the Pico Envirotec written consent of Patrick G. Killeen. (up to $1,000): Gem Systems Geotech Ltd. Thermo Fisher Scientific CONTENTS Exploration TRENDS & DEVELOPMENTS 4 MOVING RIGHT ALONG IN 2011 21 Drill-hole Methods March 2012 4 CORPORATE HIGHLIGHTS 22 Ground Electromagnetic Methods 23 Gravity Surveying 8 AIRBORNE GEOPHYSICAL SURVEYING 23 Induced Polarization 13 Airborne Data Acquisition and Processing 24 Ground Magnetic surveying 15 Aeromagnetic Surveying 25 Ground Penetrating Radar (GPR) Complimentary 16 Airborne Electromagnetic Surveying 25 Seismic PM no. 40069240 8 1 Airborne Gamma-ray Spectrometric Surveying Cover photo: 18 Airborne Gravity Surveying 26 Companies and Websites Geotech flying a 26 Abbreviations VTEM and magnetic 19 GROUND SURVEY TECHNIQUES survey in Fiji 20 Physical Rock Properties Credit: Geotech and Elemental Analysis 20 Data Processing and Positioning Supplement to Feb. 27, 2012 edition of The Northern Miner (Vol. 98, No. 2) 3 EXPLORATION TRENDS & DEVELOPMENT IN 2012 MOVING RIGHT ALONG IN 2011 Much like the economy in general, air- exploration budgets. In addition, some Natural field EM surveying saw even more borne contract surveying started to come companies added gamma-ray detectors to attention and the AFMAG system is now out of the doldrums in 2011. Additional the transmitter loops of their heli-borne available in fixed-wing and helicopter ver- aircraft were put into service, and in EM systems. The trend of increasing the sions. There were signs that the UAV, in Canada, there was a fair amount of gov- number of geophysical sensors on survey which interest seemed to peak about 2005, ernment survey work, both provincial aircraft continued. Airborne gravimeters is not yet dead. Advances in processing and federal. There was robust gold explo- became lighter and smaller, with two new- EM and other data were reported by at ration activity reported in Mexico, Cana- generation versions developed in 2011. least five companies, and included more da, and West Africa, as well as diamond The year also saw increasing use of air- 3-D solutions, modelling and inversions, exploration activity in Canada. It has borne gravity and to a lesser extent, gravity plus a new radon background-removal been called a healthy level of activity, not gradiometer surveys for mineral explora- process for gamma-ray spectrometry. To the unsustainable activity of a boom. In- tion. However, the number of contracted explore deeper with EM, higher sensitivity creased levels of exploration activity were gradiometer mineral surveys was limited is needed and in 2011 there was increased also reported in Asia, Indonesia, Papua by the number of systems available world- demand for B-field EM surveys, and great- New Guinea, North and South Amer- wide (10, including a new one in 2011) and er use of SQUID B-field sensors to obtain ica (notably Brazil), and Mongolia. The because the surveys are very expensive. Al- the required sensitivity. In a significant high level of activity in West Africa and though the new information from the grav- scientific breakthrough, a ”room-tempera- the sub-Sahara area is partially a result ity gradiometer tensors is attractive, only the ture” B-field sensor with the sensitivity of a of junior exploration companies finding tensor zz is widely used. The other tensors High Temperature SQUID was developed. more opportunities there. That, in turn, yield information in cases with simple geol- Ground geophysics saw the develop- led to more small airborne contractors ogy, but are difficult to interpret in complex ment of a new field-portable X-ray lab, taking on international work in 2011. geology, and so are mainly used as input to new borehole logging tools for density An increased number of ground and inversions. and three-component EM, new logging borehole surveys were also conducted at The number of companies flying heli- services; three new ground TDEM sys- greenfield projects last year. borne time-domain EM (TDEM) systems tems, new resistivity/IP equipment, new Radiometric surveying saw a resur- increased and three completely new heli magnetic susceptibility/conductivity me- gence in 2011, with steadily increasing TDEM systems with novel features were ters, new Spectral IP equipment, (both sales of airborne and ground systems to introduced in 2011. Manufacturers in- surface and borehole) and a new genera- replace aging systems, to supplement ex- creased the diameter of their transmitter tion GPR instrument for ice-thickness isting systems, and as a result of increased loops yet again to penetrate even deeper. profiling on winter roads. CORPORATE HIGHLIGHTS Abitibi Geophysics of Val d’Or, Que., began several signifi- airborne gravity and combined EM-4H/spectrometry surveys cant new projects in 2011, including borehole EM and sonic on the Kamchatka Peninsula and in the Amur region of Russia. logging projects in Portugal and Ireland, a physical properties As the first stage of a large, two-year regional government proj- logging program on a potash development project in Eritrea, ect, the company completed an airborne gravity survey over a and borehole gravity field operations. On the R&D front, the 160,000 sq. km area in northern Russia using a GT-2A. AGP also company received a new EM sensor with noise levels and sen- flew an interesting magnetometer test survey for a specialized ap- sitivity better than High Temperature SQUID sensors in com- plication, and test flew the new version of the GT-2A gravimeter mon geophysical use from RMIT University in Australia. Abiti- from Gravimetric Technologies, also based in Moscow. bi Geophysics also signed a co-founding agreement with the Aeroquest International of Mississauga, Ont. merged its Université du Québec en Abitibi-Témiscamingue (UQAT) to Airborne Geophysics Division (comprised of Aeroquest Sur- create the International Laboratory for Mining Geophysics veys and UTS Aeroquest) into one entity called Aeroquest (ILMG), which started operations in 2011. Located in Val d’Or, Airborne in December 2010. The group spent much of 2011 ILMG will work on developing integrated geophysical solutions focusing on its growth model and streamlining processes for for the discovery and characterization of mineralized geological business development. systems. Initial government funding of the lab was augmented Saskatoon-based Discovery International Geophysics ex- by an ongoing financing campaign, with long-term funding to panded operations with new business partnerships in Africa come from royalties and licences. and South America. The company offers TEM surveys using the In 2011, Moscow-based Aerogeophysica (AGP) continued high-temperature (liquid nitrogen) SQUID manufactured by Su- surveys that had been started in 2010 for government projects pracon AG of Jena, Germany, and developed by the